Journal articles on the topic 'API 650 Tanks'

This paper presents the results of an investigation into the frangible joint behavior of tanks designed to API 650 rules. In such tanks, the roof-to-shell joint is intended to fail in the event of overpressurization, venting the tank and containing any remaining fluid. The reasoning behind present API design formulas is reviewed. Combustion analyses, structural analyses, and the results of testing are presented. Results show that higher pressures are reached before frangible joint failure than predicted by the present API 650 calculation. One consequence is that (for empty tanks) uplift of the bottom can be expected to occur more frequently than predicted using API 650. However, uplift does not necessarily mean bottom failure. Instead, the relative strength of the shell-to-bottom and roof-to-shell joints will determine failure. This ratio is larger for larger tanks. Recommendations are made as to possible changes in the design approach of API 650.

The analysis of tank nozzles for API 650, (American Petroleum Institute, 1998, API Standard 650, 10th ed.) tanks is a complex problem. Appendix P of API 650 provides a method for determining the allowable external loads on tank shell openings. The method in Appendix P is based on two papers, one by Billimoria and Hagstrom, 1997, ASME Paper No. 77-PVP-19 and the other by Billimoria and Tam 1980, ASME Paper No. 80-C2/PVP-5. Although Appendix P is optional, the industry has used it for a number of years for large diameter tanks. For tanks less than 120feet(33.6m) in diameter this Appendix is not applicable. In previously published papers, the authors used finite element analysis (FEA) to verify the experimental results reported by Billimoria and Tam for low-type nozzles. The analysis showed the variance between stiffness coefficients and stresses obtained by FEA and API 650 methods for tanks. In this paper, the authors have expanded the scope to include almost any size of nozzle as well as tank size. Stress factors for nozzles at different elevations on the shell are provided. Nozzles located away from a discontinuity are analyzed based on the method provided by the Welding Research Council (WRC), New York, Bulletin No. 297, 1987. Stress reduction factors have been developed using FEA for nozzles located closer to a discontinuity. Mathematical equations are provided together with the curves for the stress factors. The results of this paper have been incorporated into Appendix P of API 650 with the Addendum 3 of the 10th edition which was issued in 2003.

Liquid-storage tanks, designed as per the minimum requirements of API Standard 650 (1996), AWWA Standard D100 (1996), or any other design standard, should not be expected to remain fully elastic, or undamaged, when subjected to design ground shaking. Forces prescribed in design standards are only a fraction of those obtained from a linear elastic (no damage) response analysis. Force reductions are based on the expected overstrength and ductility of the system. However, there are no practical methods to quantify the effects of these reductions on potential damage to tanks. Some type of nonlinear analysis is needed to assess the tank's desired performance objectives. This paper presents a simplified nonlinear analysis for performance-based seismic design of tanks. It also presents a method of strengthening tanks by energy-dissipating base anchors. The simplified nonlinear analysis is illustrated for an unanchored tank, a tank anchored with traditional anchors, and a tank anchored with energy-dissipating anchors.

The paper deals with the analysis of reliability and safety of a welded tank for the storage of oil, which is located in the Czech Republic. The oil tank has a capacity of 125 thousand cubic meters. It is one of the largest tanks of its kind in the world. Safety is ensured by a steel outer intercepting shell and a double bottom. The tank was modelled in the programme ANSYS. The computational model was developed using the finite element method – elements SHELL181. A nonlinear contact problem was analysed for the simulation of the interaction between the bottom plate and foundation. The normative approach in design and check of tanks according to standards API 650, ČSN EN 14015, EEMUA 159 and API 653 is mentioned. The dominant loading of the filled tank is from oil. The normative solution is based on the shell theory, which considers constant wall thickness. For real tanks sheet thicknesses of individual courses increase with increasing depth. Stochastic sensitivity analysis was used to study the effect of the variability of the thickness of the ith course on the stress of adjacent courses. The Latin Hypercube Sampling method was implemented during analysis.

POME merupakan produk samping dari produksi minyak kelapa sawit dengan rasio terkandung dalam kelapa sawit 58.3%. POME dapat dimanfaatkan untuk dijadikan biogas dengan teknologi pengolahan proses anaerobic menggunakan tanki berpengaduk/Continuous Stirred Tank Reactor (CSTR). Tujuan dari penelitian ini adalah melakukan review dan analisis digester tank dengan fluida POME berdasarkan standard American Petroleum Institute yaitu API 650: Welded Steel Tanks for Oil Storage menggunakan variable design point method untuk menentukan ketebalan minimum pada setiap shell tergantung pada kedalamannya, sehingga setiap shell dapat memiliki ketebalan yang berbeda sehingga dapat memperkecil volume material dan biaya.Kemudian dilakukan simulasi dengan metode elemen hingga dengan beban dari tekanan hidrostatik yang menghasilkan tegangan maksimum 154.88 MPa, serta deformasi maksimum 5 mm dan beban dari gaya angin yang menghasilkan tegangan maksimum 1.31 MPa, serta deformasi maksimum 0.5 mm, lalu dibandingkan dengan sifat mekanik material bahwa yield strength terjadi pada tegangan 250-395 MPa sehingga tebal shell hasil perhitungan adalah aman. Kemudian dibandingkan ketebalan minimum hasil perhitungan dengan desain konstruksi yang hasilnya adalah desain konstruksi memiliki tebal yang lebih besar dari perhitungan tebal minimum sehingga desain konstruksi yang akan dipakai adalah aman.

Tangki merupakan wadah penyimpanan yang sering dipakai di berbagai industriseperti petrokimia, pengilangan, dan perminyakan. Tangki penyimpanan tidak hanya menjadi tempat penyimpanan untuk produk dan bahan baku tetapi juga menjaga kelancaran ketersediaan produk dan bahan baku. Selain itu, tangki juga dapat menjaga produk atau bahan baku dari kontaminan. Minyak kelapa murni adalah minyak yang dibuat dari bahan baku kelapa segar. Minyak kelapa murni memiliki daya simpan lebih dari 12 bulan sehingga diperlukan tangki penyimpanan yang memadai demi menjaga produk dari kontaminasi. ASTM 304, ASTM 316L, dan S32304 merupakan stainless steel yang digunakan untuk material plat tangki penyimpanan minyak kelapa murni. Stainless steel merupakan baja tahan korosi sehingga diharapkan dapat menjaga kualitas produk minyak kelapa murni. Penelitian ini bertujuan untuk merancang tangki penyimpanan minyak kelapa murni menggunakan stainless steel. Tangki penyimpanan dirancang memiliki kapasitas 75 m3. Tangki dirancang dengan membandingkan antara API 650 dengan BS 2654. Hasil perhitungan didapatkan ketebalan plat shell aktual 6 mm, ketebalan plat dasar aktual 6 mm, ketebalan plat dasar annular aktual 8 mm, dan ketebalan atap aktual 6 mm. Berdasarkan hasil perhitungan, tegangan pada tangki masih memenuhi syarat karena tegangan ijin tangki lebih besar dari tegangan akibat beban statis, tegangan circumferensial, dan tegangan longitudinal. Dengan demikian, desain tangki penyimpanan dapat dikatakan aman.Kata kunci: API 650, BS 2654, minyak kelapa murni, stainless steel, tangki penyimpananTank is a storage container that is often used by various industries such as petrochemical, refining, and petroleum. Storage tanks isnot only a storage for products and raw materials but also maintain the fluency availability of products and raw materials. Furthermore, the tank can also keep products or raw materials from contaminants. Virgin coconut oil is oil made from fresh coconut. Virgin coconut oil has storability of more than 12 months, so that adequate storage tanks are required to keep the product from contamination. ASTM 304, ASTM 316L, and S32304 are stainless steels used for the material of the virgin coconut oil storage tank. Stainless steel is corrosion resistant steel so it is expected to maintain the quality of virgin coconut oil product. This research aims to design storage tank of virgin coconut oil using stainless steel material. The storage tank is designed to have a capacity of 75 m3. The tank is designed by comparing between API 650 and BS 2654. The calculation results obtained the actual thickness of the shell plate is 6 mm, the actual bottom plate thickness is 6 mm, the actual annular bottom plate thickness is 8 mm, and the actual roof thickness is 6 mm. Based on the calculation, tank stress is still accepted because the allowable stress of tank is larger than the stress due static load, circumferential stress, and longitudinal stress. Thus, the design of storage tank is safe.Keywords: API 650, BS 2654, stainless steel, storage tank, virgin coconut oil

Field evidence has established that strong earthquakes can cause severe damage or even collapse of liquid storage tanks. Many tanks worldwide are built near the coast on soft soils of marginal quality. Because of the difference in stiffness between the tank (rigid), foundation (rigid) and the soil (flexible), soil-foundation-structure interaction (SFSI) has an important effect on the seismic response, often causing an elongation of the period of the impulsive mode. This elongation is likely to produce a significant change in the seismic response of the tank and will affect the loading on the structure. An issue not well understood, in the case of unanchored tanks, is uplift of the tank base that usually occurs under anything more than moderate dynamic loading. This paper presents a comparison of the loads obtained using “Appendix E of API STANDARD 650” of the American Petroleum Institute and the “Seismic Design of Storage Tanks” produced by the New Zealand Society for Earthquake Engineering. The seismic response assessed using both codes is presented for a range of tanks incorporating a range of the most relevant parameters in design. The results obtained from the analyses showed that both standards provide similar base shear and overturning moment; however, the results given for the anchorage requirement and uplift are different.

The present paper investigates sloshing effects on the earthquake design of horizontal-cylindrical and spherical industrial vessels. Assuming small-amplitude free-surface elevation, a linearized sloshing problem is obtained, and its solution provides sloshing frequencies, modes, and masses. Based on an “impulsive-convective” decomposition of the container-fluid motion, an efficient methodology is proposed for the calculation of seismic force. The methodology gives rise to appropriate spring-mass mechanical models, which represent sloshing effects on the container-fluid system in an elegant and simple manner. Special issues, such as the deformability of horizontal-cylindrical containers or the flexibility of spherical vessel supports, are also taken into account. The proposed methodology can be used to calculate the seismic force, in the framework of liquid container earthquake design, and extends the current design practice for vertical cylindrical tanks stated in existing seismic design specifications (e.g., API Standard 650 and Eurocode 8). The methodology is illustrated in three design examples.

Since the wall thicknesses of most large LPG storage tanks are thin while their diameters are large, their structural integrity is one of the most important design factors. The tanks are mainly located near the waterfront for efficient transport and accessibility. This leads to exposure to wind loads, which should be considered in the design of the tanks. This paper describes an analytical technique for determining the structural integrity of a 45m diameter-LPG storage tank in the case of a wind load based on API 620 code. A finite element model for the tank was made using shell elements and analyzed under 50 m/s wind. The calculated maximum von-Mises stress was 103 MPa whereas the yield strength of tank’s material is 222 MPa. This result shows that the structural integrity of the tank is assured.

Lapangan pengolahan minyak dan gas menyimpan banyak fasilitas peralatan berupa tangki pelat baja yang melayani penyimpanan fluida diantaranya berupa minyak. Beberapa masalah yang mungkin terjadi pada tangki yang telah beroperasi sekian lama adalah penurunan pada pondasi. Suatu tangki yang telah beroperasi sekitar 20 tahun terindikasi secara visual telah mengalami kemiringan. Indikasi awal terhadap kemiringan tersebut adalah telah terjadinya penurunan tidak seragam (differential settlement) pada pondasi tangki. Penelitian dilakukan untuk mengetahui apakah tangki tersebut masih dapat digunakan dan dalam kondisi aman untuk dioperasikan atau memerlukan perbaikan. Penelitian ini akan mengevaluasi penurunan yang terjadi pada tangki tersebut sesuai metode analisis pada American Petroleum Institute (API) 653. API 653, Tank Inspection, Repair, Alteration, and Reconstruction, fifth edition memberikan rekomendasi metoda untuk melakukan evaluasi terhadap penurunan tanah (settlement). Hasil penelitian menunjukkan bahwa penurunan tangki di beberapa titik telah melebih batas penurunan maksimum sehingga diperlukan adanya perbaikan lebih lanjut.

Salah satu peralatan yang banyak terdapat dalam industri migas adalah tangki penimbun. Keberadaan tangki penimbun sangat vital pada produksi industri perminyakan. Sering terjadi kecelakaan yang menimpa tangki timbun dalam industri migas yang menimbulkan kerugian besar. Pada tulisan ini dibahas tentang corrosion rate dan remaining life pada aboveground existing fixed cone roof tank dalam kondisi in-service dengan API Std 653 sebagai standar acuan.

Storage tank merupakan tangki penyimpanan untuk fluida cair dan gas. Dalam penelitian ini, storage tank digunakan untuk proses loading dan unloading fluida cair dan gas dengan tujuan untuk melihat fenomena yang akan terjadi akibat kekeliruan karena venting tidak dibuka yang akan menimbulkan potensi ledakan untuk proses loading dan bahaya collapse untuk proses unloading. Parameter yang digunakan adalah variasi laju alir volumetrik terhadap waktu dan tekanan ketika ledakan serta collapse. Adapun spesifikasi dari storage tank yang dibuat sesuai dengan desain dan rancangan dari API 620 dan 650 dengan ketinggian 50 cm, diameter 20.32 cm dan ketebalan 0.7 cm dari bahan carbon steel. Simulator keamanan dari storage tank ini menekankan pada aspek fenomena dari keamanan pengoperasian storage tank. Indikator untuk bahaya ledakan adalah balon, karet pipet dan plastik tebal, sementara untuk simulasi bahaya collapse, indikator yang digunakan adalah botol plastik dengan ukuran 450, 700 dan 1600 ml. Setiap indikator tersebut dimaksudkan sebagai sebuah simulator dari bahaya keamanan pada storage tank, tetapi tidak merepresentasikan daripada kekuatan tangki. Indikator yang digunakan untuk melihat fenomena ledakan saat proses loading maupun collapse saat proses unloading menekankan pada aspek penyadaran terhadap orang atau operator yang bersangkutan bahwa untuk setiap kekeliruan dari proses loading maupun unloading akan mengakibatkan konsekuensi. Dalam skala industri yang lebih besar dan dengan fluida yang lebih sensitif dan berbahaya, kekeliruan ini bisa fatal dan tidak bisa ditolerir. Hasil dari penelitian dan uji simulasi kemanan tersebut untuk proses loading fluida cair diperoleh tekanan maksimumnya 1 barg untuk indikator karet pipet pada nilai laju alir volumetrik pada 30 l/min dengan waktu loading 19.48 detik. sementara untuk proses loading fluida gas mempunyai tekanan maksimum sebesar 0.6 barg untuk indikator karet pipet pada nilai laju alir volumetrik 30 l/min dengan waktu pengisian adalah 11.91 detik untuk indikator karet pipet. sementara untuk proses unloading fluida cair botol berukuran 1600 ml menunjukan ketahanan terhadap collapse yang lebih kuat (lama) dengan waktu 0.58 detik untuk laju alir volumetrik maksimumnya. Terakhir untuk proses unloading fluida gas bahwa ketahanan botol berukuran 400 ml lebih kuat dengan waktu collapse yaitu 13.61 detik. Adapun indikator optimum untuk penelitian pada proses loading adalah dengan menggunakan karet pipet, dan proses unloading dengan menggunakan botol berukuran 700 ml.

The article is dedicated to the 80th anniversary of the birth of Dr. habil. in Psychology, Professor A.I. Krupnov. It analyzes the continuity and achievements of scientific research on differential psychology in Russian science. Advantages of A.I. Krupnov’s psychological researches and the employees of Psychological Institute of Russian Academy of Education are revealed. The man of the year developed a holistic conceptual foundation of the personality traits’ formation, combining the interaction of direct-sensory and conscious components of human activities. Theoretically grounded and practically demanded aspects of the activity of person’s self-regulation were presented in A.I. Krupnov’s integral concept. Along with article author’s ideas about the regulatory experience of the person providing independence and conscious self-regulation in the process of the organization and implementation of activity are considered. Reconstruction of the appeal to human experience while studying its psychological characteristics in the regulatory context combines the interaction of valuable, reflexive, operational, communicative and habitually-activated components of the activities’ organization and implementation. A person acquires the ability to set tasks through regulatory experience. He chooses them from among those imposed by the environment and generates new tasks independently, and then consistently achieves their successful solution.

Abstract Context: Certified athletic trainers who serve as Approved Clinical Instructors (ACIs) in the collegiate setting are balancing various roles (eg, patient care and related administrative tasks, clinical education). Whether this balancing act is associated with role strain in athletic trainers has not been examined. Objective: To examine the degree of, and contributing factors (eg, socialization experiences, professional and employment demographics, job congruency) to, role strain in collegiate ACIs. Design: Cross-sectional survey design. Setting: Geographically stratified random sample of ACIs affiliated with accredited athletic training education programs at National Collegiate Athletic Association (NCAA) Division I, II, and III institutions. Patients or Other Participants: 118 collegiate ACIs (47 head athletic trainers, 45 assistant athletic trainers, 26 graduate assistant athletic trainers). Main Outcome Measure(s): The Athletic Training ACI Role Strain Inventory, which measures total degree of role strain, 7 subscales of role strain, socialization experiences, professional and employment characteristics, and congruency in job responsibilities. Results: A total of 49% (n = 58) of the participants experienced a moderate to high degree of role strain. Role Overload was the highest contributing subscale to total role strain. No differences were noted between total role strain and role occupant groups, NCAA division, or sex. Graduate assistant athletic trainers experienced a greater degree of role incompetence than head athletic trainers did (P = .001). Division II ACIs reported a greater degree of inter-role conflict than those in Division I (P = .02). Female ACIs reported a greater degree of role incompetence than male ACIs (P = .01). Those ACIs who stated that the ACI training provided by their institution did not adequately prepare them for the role as an ACI experienced greater role strain (P < .001). Conclusions: The ACIs in the collegiate setting are experiencing role strain in balancing their roles as health care providers, clinical educators, and administrators. Methods to reduce role strain need to be considered.

The Fourier solution for thin shell equations models pressure vessels as continuous simply connected surfaces with local loads. The technique allows placement of tractions with combinations of radial, shear, and axial components. Unlike Bijlaard, the solution in this paper includes loads placed at any position along the cylinder. Stiffness and the enhanced load-carrying capacity that internal pressure gives to thin vessels can be simulated. Numerical convergence problems are reduced by an improved displacement-load algorithm, and by use of load sites that allow the circular functions to be compactly grouped. A variety of loading distributions may be analyzed including large and small nozzles near and away from centerlines. Both rectangular and circular attachments are simulated. Through superposition, multiple attachments with their own loads may be examined. The attachments to the vessel may be either rigid or soft. A comparison to analytical results from Bijlaard shows excellent agreement. Comparisons with experimental tests on an API-650 nozzle on a storage tank are in good agreement. Variations between experimental and calculated results are primarily caused by assuming a simply supported base in the calculation, whereas in the experimental test, the base is more nearly fixed.

Abstract An integrated reservoir characterization of Seminole San Andres Unit was conducted using outcrop and subsurface data. The high-frequency cycles and rock-fabric facies identified on outcrop and cores were used to correlate wireline logs. Reservoir and simulation models of the outcrop and a two-section area of the Seminole San Andres field were constructed using rock-fabric units within high-frequency cycles (HFC's) as a geologic framework. Simulations were performed using these models to investigate critical factors affecting recovery. High-frequency cycles and rock-fabric units are the two critical scales for modeling shallow-water carbonate ramp reservoirs. Descriptions of rock-fabric facies stacked within high-frequency cycles provide the most accurate framework for constructing geologic and reservoir models because discrete petrophysical functions can be fit to rock fabrics and fluid flow can be approximated by the kh ratios among rock-fabric flow units. Permeability is calculated using rock-fabric-specific transforms between interparticle porosity and permeability. Core analysis data showed that separate-vug porosity has a very strong effect on relative permeability and capillary pressure measurements. The stratigraphic features of carbonates can be observed in stochastic realizations only when they are constrained by rock-fabric flow units. Simulation results from these realizations are similar in recovery but different in production and injection rates. Scale-up of permeability in the vertical direction was investigated in terms of the ratio of vertical permeability to horizontal permeability (kvh). This ratio decreases exponentially with the vertical grid-block size up to the average cycle size of 20 ft (6.1 m) and remains at a value of 0.06 for a grid-block size of more than 20 ft >6.1 m), which is the average thickness of high- frequency cycles. Simulation results showed that critical factors affecting recovery efficiency are stacking patterns of rock-fabric flow units, kvh ratio, and dense mudstone distribution. Introduction More than 9 billion stock-tank barrels of oil has been produced from shallow-water ramp carbonates of the San Andres Formation, West Texas and New Mexico. Because reservoirs in this play are highly heterogeneous and stratified, waterflood recovery averages only 30 percent, and more oil can be recovered if reservoir characterization is done along with infill drilling and CO2 flooding programs. Major issues in characterizing carbonate reservoirs are geologic framework, interwell heterogeneity including rock-fabric facies and permeability structure, scale-up of petrophysical properties, and factors affecting recovery efficiency. Because well spacings in most San Andres fields in West Texas and New Mexico are greater than 600 ft >200 m), outcrops on the Algerita Escarpment in the Guadalupe Mountains, Texas and New Mexico, provide an opportunity to define geologic framework, to quantify interwell heterogeneity, and to develop methods for scale-up of petrophysical properties. Applying the results of outcrop investigations to subsurface reservoirs leads to the development of new methods and techniques for constructing 3-D reservoir and flow models for simulating fluid flow and forecasting performance. The Seminole San Andres Unit (SSAU) lies on the northeastern margin of Central Basin Platform (Fig. 1) immediately south of the San Simon Channel. It covers approximately 23 mi2 and contains more than 600 wells. The field, discovered in 1936, is a solution-gas-drive reservoir with a small initial gas cap and has an estimated original oil in place of 1,100 MMSTB. Production comes from the Upper San Andres Formation and the upper part of the Lower San Andres Formation. The crude is 35 API and has an initial formation volume factor (FVF) of 1.39 and a solution-gas ratio of 684 SCF/STB.

Summary This paper evaluates published correlations and neural-network models for bubblepoint pressure (pb) and oil formation volume factor (Bo) for their accuracy and flexibility in representing hydrocarbon mixtures from different locations worldwide. The study presents a new, improved correlation for pb based on global data. It also presents new neural-network models and compares their performances to numerical correlations. The evaluation examines the performance of correlations with their original published coefficients and with new coefficients calculated based on global data, data from specific geographical locations, and data for a limited oil-gravity range. The evaluation of each coefficient class includes geographical and oil-gravity grouping analysis. The results show that the classification of correlation models as most accurate for a specific geographical area is not valid for use with these two fluid properties. Statistical and trend performance analysis shows that some published correlations violate the physical behavior of hydrocarbon fluid properties. Published neural-network models need more details to be reproduced. New developed models perform better but suffer from stability and trend problems. Introduction Solutions to reservoir performance problems at various stages of reservoir life require knowledge of the physical properties of reservoir fluids at elevated pressures and temperatures. The pressure/volume/temperature (PVT) properties for reservoir hydrocarbon mixtures are usually obtained from laboratory analysis of preserved or recombined reservoir fluid samples. Because experimental facilities are not always available, other means for estimating PVT properties have been developed; during the last 50 years, many correlations have been developed for this purpose. PVT properties are a function of temperature, pressure, composition of the hydrocarbon mixture, and the presence of paraffins and impurities. The performance of an empirical model depends mainly on how accurately a correlation model represents this mixture under specific conditions. The purpose of this paper is to study the performance of models available in the literature, based on published experimental data. The study was carried out to model the pb and the Bo at and below the pb. Both empirical correlations and neural-network models were considered to reach a clearer understanding about what model to use and what to expect. A large global database gathered for this study was used to develop correlation models that predict oil properties better than existing models. Literature Review Since the 1940's, engineers in the United States have realized the importance of developing empirical correlations for PVT properties. Studies carried out in this field resulted in the development of new correlations. Several studies of this kind were published by Katz,1 Standing,2 Lasater,3 and Cronquist.4 For several years, these correlations were the only source available for estimating PVT properties when experimental data were unavailable. In the last 20 years there has been an increasing interest in developing new correlations for crude oils obtained from various regions in the world. Vazquez and Beggs,5 Glaso,6 Al-Marhoun,7,8 and Abdul-Majeed and Salman9 carried out some of the recent studies. The following presents a review of the best-known correlation models published in the literature. A summary of these published correlation models is provided in the Appendix (Tables 1 and 2), including the forms of correlation used, errors reported by each author, and details of the data used for each development. Empirical Correlations. In 1942, Katz1 published a graphical correlation for predicting Bo. Katz1 used U.S. midcontinent crude to develop his correlations. The graphical correlation uses reservoir temperature, pressure, solution gas/oil ratio (GOR), oil gravity, and gas gravity. The correlations were presented only in graphical form and were hard to use because they required the use of graphs and calculations in combination. In 1947, Standing2,10,11 published his correlations for pb and for Bo. The correlations were based on laboratory experiments carried out on 105 samples from 22 different crude oils in California, U.S.A. The correlations treated the pb and the Bo as a function of the reservoir temperature, GOR, oil gravity, and gas gravity. Standing's2,10,11 correlations were the first to use these four parameters, which now are commonly used to develop correlations. In fact, these correlations are the most widely used in the oil industry. Lasater3 in 1958 presented a new correlation model based on 158 samples from 137 reservoirs in Canada, the U.S., and South America. His correlation was only for pb. It is based on standard physical chemical equations of solutions. It uses Henry's law constant and the observation that the bubblepoint ratio at different temperatures is equal to the absolute temperatures ratio for hydrocarbon systems not close to the critical point. The correlation was presented in graphical form and was used as a lookup chart. An advantage of Lasater's3 correlation is the wide variety of data sources used to develop the correlation. In 1972, Cronquist4 presented a ratio correlation based on 80 data points from 30 Gulf Coast reservoirs. The correlation is useful for the analysis of depletion-drive reservoirs when PVT analysis is not available. The method was presented in graphical form and requires an estimation of average reservoir properties. In 1976, Vazquez and Beggs5 published correlations for GOR and Bo. They started categorizing oil mixtures into two categories, above 30°API gravity and below 30°API gravity. They also pointed out the strong dependence on gas gravity and developed a correlation to normalize the gas-gravity measurement to a reference separation pressure of 100 psi. This eliminated its dependence on separation conditions. More than 6,000 data points from 600 laboratory measurements were used in developing the correlations. Glaso6 in 1978 developed correlations for pb, formation volume factor, GOR, and oil viscosity for North Sea hydrocarbon mixtures. The main feature of Glaso's6 correlations is that they account for paraffinicity by correcting the flash stock-tank-oil gravity to an equivalent corrected value with reservoir temperature and oil viscosity. They also account for the presence of nonhydrocarbons on saturation pressure by using correction factors for the presence of CO2, N2, and H2S in the total surface gases. A total of 45 oil samples, most of which came from the North Sea region, were used in the development of these correlations. In 1988, Al-Marhoun8 published new correlations for estimating pb and Bo for Middle East oils. A total of 160 data sets from 69 Middle Eastern reservoirs were available for the correlation development. Al-Marhoun's7,8 correlations were the first to be developed for Middle East reservoirs.

Introduction Researchers around the globe are utilizing crowdsourcing tools to reach respondents for quantitative and qualitative research (Chambers & Nimon, 2019). Many social science and business journals are receiving studies that utilize crowdsourcing tools such as Amazon Mechanical Turk (MTurk), Qualtrics, MicroWorkers, ShortTask, ClickWorker, and Crowdsource (e.g., Ahn, & Back, 2019; Ali et al., 2021; Esfahani, & Ozturk, 2019; Jeong, & Lee, 2017; Zhang et al., 2017). Even though the use of these tools presents a great opportunity for sharing large quantities of data quickly, some challenges must also be addressed. The purpose of this guide is to present the basic ideas behind the use of crowdsourcing for survey research and provide a primer for best practices that will increase their validity and reliability. What is crowdsourcing research? Crowdsourcing describes the collection of information, opinions, or other types of input from a large number of people, typically via the internet, and which may or may not receive (financial) compensation (Hargrave, 2019; Oxford Dictionary, n.d.). Within the behavioral science realm, crowdsourcing is defined as the use of internet services for hosting research activities and for creating opportunities for a large population of participants. Applications of crowdsourcing techniques have evolved over the decades, establishing the strong informational power of crowds. The advent of Web 2.0 has expanded the possibilities of crowdsourcing, with new online tools such as online reviews, forums, Wikipedia, Qualtrics, or MTurk, but also other platforms such as Crowdflower and Prolific Academic (Peer et al., 2017; Sheehan, 2018). Crowdsourcing platforms in the age of Web 2.0 use remote labor recruited via the internet to assist employers complete tasks that cannot be left to machines. Key characteristics of crowdsourcing include payment for workers, their recruitment from any location, and the completion of tasks (Behrend et al., 2011). They also allow for a relatively quick collection of data compared to data collection in the field, and participants are rewarded with an incentive—often financial compensation. Crowdsourcing not only offers a large participation pool but also a streamlined process for the study design, participant recruitment, and data collection as well as integrated participant compensation system (Buhrmester et al., 2011). Also, compared to other traditional marketing firms, crowdsourcing makes it easier to detect possible sampling biases (Garrow et al., 2020). Due to advantages such as reduced costs, diversity of participants, and flexibility, crowdsourcing platforms have surged in popularity for researchers. Advantages MTurk is one of the most popular crowdsourcing platforms among researchers, allowing Requesters to submit tasks for Workers to complete (Cummings & Sibona, 2017). MTurk has been used as an online crowdsourcing platform for the recruitment of human subjects for research purposes (Paolacci & Chandler, 2014). Research has also shown MTurk to be a reliable and cost-effective tool, capable of providing representative data for research in the behavioral sciences (e.g., Crump et al., 2013; Goodman et al., 2013; Mason & Suri, 2012; Rand, 2012; Simcox & Fiez, 2014). In addition to its use in social science studies, the platform has been used in marketing, hospitality and tourism, psychology, political science, communication, and sociology contexts (Sheehan, 2018). To illustrate, between 2012 and 2017, more than 40% of the studies published in the Journal of Consumer Research used crowdsourcing websites for their data collection (Goodman & Paolacci, 2017). Disadvantages Although researchers have assessed crowdsourcing platforms as reliable and cost-effective for data collection in the behavioral sciences, they are not exempt of flaws. One disadvantage is the possibility of unsatisfactory data quality. In fact, the virtual setting of the survey implies that the investigator is physically separated from the participant, and this lack of monitoring could lead to data quality issues (Sheehan, 2018). In addition, participants in survey research on crowdsourcing platforms are not always who they claim to be, creating issues of trust with the data provided and, ultimately, the quality of the research findings (McGonagle, 2015; Smith et al., 2016). A recurrent concern with MTurk workers, for instance, is their assessment as experienced survey takers (Chandler et al., 2015). This experience is mainly acquired through completion of dozens of surveys per day, especially when they are faced with similar items and scales. Smith et al. (2016) identified two types of problems performing data collection using MTurk; namely, cheaters and speeders. As compared to Qualtrics—which has a strict screening and quality-control processes to ensure that participants are who they claim to be—MTurk appears to be less exigent regarding the workers. However, a downside for data collection with Qualtrics is more expensive fees—about $5.00 per questionnaire on Qualtrics, against $0.50 to $1.50 on MTurk (Ford, 2017). Hence, few researchers were able to conduct surveys and compare respondent pools with Qualtrics or other traditional marketing research firms (Garrow et al., 2020). Another challenge using MTurk arises when trying to collect a desired number of responses from a population targeted to a specific city or area (Ross et al., 2010). The issues inherent to the selection process of MTurk have been the subject of investigations in several studies (e.g., Berinsky et al., 2012; Chandler et al., 2014; 2015; Harms & DeSimone, 2015; Paolacci et al., 2010; Rand, 2012). Feitosa et al. (2015) pointed out that international respondents may still identify themselves as U.S. respondents with the use of fake addresses and accounts. They found that 5% to 10% of participants identifying themselves as U.S. respondents were actually from overseas locations. Moreover, Babin et al. (2016) assessed that the use of trap questions allowed researchers to uncover that many respondents change their genders, ages, careers, or income within the course of a single survey. The issues of (a) experienced workers for the quality control of questions and (b) speeders, which, for MTurk can be attributed to the platform being the main source of revenue for a given respondent, remain the inherent issues of crowdsourcing platforms used for research purposes. Best practices Some best practices can be recommended in the use of crowdsourcing platforms for data collection purposes. Workers IDs can be matched with IDs from previous studies, thus allowing researchers to exclude responses from workers who had answered previous similar studies (Goodman & Paolacci, 2017). Furthermore, proceed to a manual assignment of qualification on MTurk prior to data collection (Litman et al., 2015; Park & Park, 2020). When dealing with experienced workers, both using multiple attention checks and optimizing the survey in a way to have the participants exposed to the stimuli for a sufficient length of time to better address the questions are also recommended (Sheehan, 2018). In this sense, shorter surveys are preferred to longer ones, which affect the participant’s concentration, and may, in turn, adversely impact the quality of their answers. Most importantly, pretest the survey to make sure that all parts are working as expected. Researchers should also keep in mind that in the context of MTurk, the primary method for measurement is the web interface. Thus, to avoid method biases, researchers should ponder whether or not method factors emerge in the latent measurement models (Podsakoff et al., 2012). As such, time-lagged research designs may be preferred as predictor and criterion variables can be measured at different points in time or administered in different platforms, such as Qualtrics vs MTurk (Cheung et al., 2017). In general, the use of crowdsourcing platforms including MTurk may be appropriate according to the research question; and the quality of data is reliant on the quality-control strategies used by researchers to enhance data quality. Trade-offs between various validity types need to be prioritized according to the research objectives (Cheung et al., 2017). From our experience using crowdsourcing tools for our own research as the editorial team members of several journals and chair of several conferences, we provide the best practices as outlined below: MTurk Worker (Respondent) Selection: Researchers should consider their study population before using MTurk for data collection. The MTurk platform should be used for the appropriate study population. For example, if the study targets restaurant owners or company CEOs, MTurk workers may not be suitable for the study. However, if the target population is diners, hotel guests, grocery shoppers, online shoppers, students, or hourly employees, utilizing a sample from MTurk would be suitable. Researchers should use the selection tool in the software. For example, if you target workers only from one country, exclude responses that came from an internet protocol (IP) address outside the targeted country and report the results in the method section. Researchers should consider the demographics of workers on MTurk which must reflect the study targeted population. For example, if the study focuses on baby boomers use of technology, then the MTurk sample should include only baby boomers. Similarly, the gender balance, racial composition, and income of people on MTurk should mirror the targeted population. Researchers should use multiple screening tools that identify quality respondents and avoid problematic response patterns. For example, MTurk provides the approval rate for the respondents. This refers to how many times a respondent is rejected for various reasons (i.e., wrong code entered). We recommend using a 90% or higher approval rate. Researchers should include screening questions in different places with different type of questions to make sure that the respondents are appropriate for your study. One way is to use knowledge-based questions about the subject. For example, rather than asking “How experienced are you with accounting practices?”, a supplemental question such as “Which of the following is a component of an income statement?” should be integrated into the study in a different section of the survey. Survey Validity: Researchers should conduct a pilot survey from MTurk workers to identify and fix any potential data quality and programming problems before the entire data set is collected. Researcher can estimate time required to complete the survey from the pilot study. This average time should be used in calculating incentive payment for the workers in such a way that the payment should equate or exceed minimum wage in the targeted country. Researchers should build multiple validity-check tools into the survey. One of them is to ask attention check questions such as “please click on ‘strongly agree’ in this question” or “What is 2+2? Please choose 5” (Cobanoglu et al., 2016) Even though these attention questions are good and should be implemented, experienced survey takers or bots easily identify them and answer them correctly, but then give random answers to other questions. Instead, we recommend building in more involved validity check questions. One of the best is asking the same question in different places and in different forms. For example, asking the age of the respondent in the beginning of the survey and then asking them the year of their birth at the end of the survey is an effective way to check that they are replying to the survey honestly. Exclude all those who answered the same question differently. Report the results of these validity checks in the methodology. Cavusoglu (2019) found that almost 20% of the surveys were eliminated due to the failure of the validity check questions which were embedded in different places and in different forms in his survey. Researchers should be aware of internet bot, which is a software that runs automated tasks. Some respondents use a bot to reply to the surveys. To avoid this, use Captcha verification, which forces respondents to perform random tasks such as moving the bar to a certain area, clicking in boxes that has cars, or checking boxes to verify the person taking the survey is not a bot. Whenever appropriate, researchers should use time limit options offered by online survey tools such as Qualtrics to control the time that a survey taker must spend to advance to the next question. We found that this is a great tool, especially when you want the respondents to watch a video, read a scenario, or look at a picture before they respond to other questions. Researchers should collect data in different days and times during the week to collect a more diverse and representative sample. Data Cleaning: Researchers should be aware that some respondents do not read questions. They simply select random answers or type nonsense text. To exclude them from the study, manually inspect the data. Exclude anyone who filled out the survey too quickly. We recommend excluding all responses filled out less than 40% of the average time to take the survey. For example, if it takes 10 minutes to fill out a survey, we exclude everyone who fills out this survey in 4 minutes or less. After we separated these two groups, we compared them and found that the speeders’ (aka cheaters) data was significantly different than the regular group. Researchers should always collect more data than needed. Our rule of thumb is to collect 30% more data than needed. For example, if 500 clean data responses are wanted, collect at least 650 data. The targeted number of data will still be available after cleaning the data. Report the process of cleaning data in the method section of your article, showing the editor and reviewers that you have taken steps to increase the validity and reliability of the survey responses. Calculating a response rate for the samples using MTurk is not possible. However, it is possible to calculate active response rate (Ali et al., 2021). It can be calculated as the raw response numbers deducted from all screening and validity check question results. For example, if you have 1000 raw responses and you eliminated 100 responses for coming from IP address outside of the United States, another 100 surveys for failing the validity check questions, then your active response rate would be 800/1000= 80%.

The behavior of aboveground storage tanks subjected to seismic excitation was investigated using numerical methods by taking flexibility of foundation into account. The hydrostatic load due to stored liquid has an axisymmetric distribution on the tank shell and base. However, during seismic events, the hydrodynamic load originating from the seismic acceleration of liquid in the tank starts to act in the direction of the earthquake motion. This leads to a nonaxisymmetric loading distribution, which may result in buckling and uplifting of the tank structure. Finite element models were created having nonlinear material properties and large deformation capabilities. Three different tank geometries with liquid height to tank radius aspect ratios of 0.67, 1.0, and 3.0 were selected representing broad, nominal, and slender tanks. These tanks were subjected to two different hydrodynamic loading based on Housner's and Jacobsen–Veletsos' pressure distributions, which forms the basis of design provisions used in American Petroleum Institute API 650 and Eurocode 8, respectively. These pressure distributions were formulated under the assumption of rigid tank wall and base. Furthermore, each tank for a given geometry was subjected to two different foundations: (1) representing a rigid foundation and (2) representing a flexible foundation. The flexible foundation was created using a series of compression-only elastic springs attached to tank base having equivalent soil stiffness. Static analysis corresponding to maximum dynamic force was performed. The finite element results for circumferential and longitudinal stress in the shell were compared with the provisions of API 650. It was found that the effect of foundation flexibility from the practical design point of view may be neglected for broad tanks, but should be considered for nominal and slender tanks.

Storage tanks operating at elevated temperatures (200 °F to 500 °F) need to consider stresses due to thermal expansions and restraints, due to the tank shell and bottom plate interactions and operating conditions in addition to the design requirements for ambient temperature tanks. Appendix M of API Standard 650 provides additional requirements and guidelines for the design of tanks operating at elevated temperatures. These are based on Karcher's method which gives a simplified procedure for determining the stresses (strain range) in the tank wall and bottom plate. A factor named “C” is used for defining the ratio of actual expansion against free expansion of the tank. Such partial expansion causes significant thermal stresses. API uses these stresses to estimate the low cycle fatigue life of the tanks. At present, a range of C values (0.25–1.0) is allowed by API without clear guidelines for selecting a suitable value. In the absence of such guidelines, a set value (like 0.85) is being used irrespective of the tank dimensions and temperature change. The restraint against free expansion is mainly a result of the friction between bottom plate, the foundation medium and the ring wall (if present). We can estimate the C factor by relating it to the friction coefficient. This is explored in the present study. This paper evaluates the current procedure and suggests an alternate method by incorporating the friction coefficient directly in the stress equations, instead of the C-factor. Use of friction coefficient provides an improved basis for selecting C and avoids some of the difficulties.

The results of wind tunnel tests indicate that there is an internal inward pressure induced by wind excitation when open-top tanks are examined, but not when close-top tanks are examined. This internal pressure is considered in many design documents outside of the U.S., however, ASCE-7 and API 650 do not explicitly address this factor. This study examined the effect of this internal pressure by conducting finite element analyses. Open-top tanks with height to diameter ratios of 0.11, 0.2, 0.5, 1.0, 2.0, and 4.0 were modeled using a finite element program. A linear bifurcation analysis and a post-buckling analysis were then conducted to verify the tank's stability when subjected to wind loading in accordance with the wind profiles specified in the selected design documents. To ensure the quality of the analyses, a study on mesh convergence and the load increment of Riks analysis was conducted. It was determined that the presence of the additional internal pressure term has a drastic impact on the buckling capacity of all the tanks examined. As a consequence, it can be concluded that the additional internal pressure generated by the wind on an open-top tank should not be neglected.

Seismic hazard represents one of the possible triggering causes for NaTech accidents in refineries and production plants. The vulnerability of steel storage tanks was evaluated within the framework of a rapid risk assessment. Tanks dataset is composed of 70 refinery items in located in various parts of Italy and the seismic calculations are performed in accordance to API 650 Annex E Standard. The paper summarizes the results of the investigation through two normalized parameters related to the masses and to the seismic load. Some trends in the solution are highlighted. The empirical fragility curve obtained from the analysis is compared with similar curves found in the literature and the resulting similarities (and dissimilarities) are critically discussed.

Keep in safe operability conditions, using the calculations to apply mechanical processes and in order to detect any anomaly that allow timely take preventive actions and repair the elements that are part of the containers in poor condition or outside the rules that govern them. In the rings using analytical methods such as the verification of thicknesses by calculating them by the methods specified in API 653 Inspection, Repair, Alteration and Reconstruction of Tanks American Petroleum Institute, finding if they are outside the appropriate regulations by comparison with what is measured in real form on the hull ring plate, whereby the method is non-destructive inspection, API 650 “Welded Steel Tanks for Petroleum Storage American Petroleum Institute (American Petroleum Institute). To carry out the relevant repairs using welding and cutting processes, assembly and maneuvers application of coatings and materials necessary according to the repair to maintain and ensure the integrity of the container improving the reliability of operation, contributing to the safety of the tanks, accessories and attached systems , as containers of highly explosive and incendiary hydrocarbon derived products.

Design of the top wind stiffeners of aboveground storage tanks designed to the requirements of API 650 is investigated. The current design methodology is based on intuition and experience without a sound technical justification. This paper investigates a diameter limit to be used in the design of the top stiffener ring by using finite-element analysis (FEA) in a parametric study. Linear bifurcation analysis (LBA) and geometrically nonlinear analysis including imperfections (GNIA) were performed on cylindrical storage tanks. By modeling tanks with different diameters and limiting the design of top stiffener ring for a diameter of 170-ft (52-m), the buckling loads are investigated. It was found that the 170-ft (52-m) diameter is a suitable upper limit to design the top stiffener rings for larger diameters.

The aim of this paper is to demonstrate how the correct application of FEM analysis can be used to find effective solutions for the design of mechanical structures. The design of the inspection openings on the tanks is being considered. There are several existing tanks of the same dimensions (20 m high and diameter 10,2 m), but they have different wall thicknesses (9,6; 15; 20 and 25 mm). For inspection purposes, assembly of manhole hatch on all tanks is required. The manhole hatch is designed applying standard API 650. All tanks are filled with the water to the top 20 m high. Several different analyses have been carried out in order to ensure that there are not too high stresses in the materials of the existing tanks due to the insertion of the manhole hatch and finally qualify construction according to EN-13445 norm. The elastic analysis shows that stresses in the material are too high and the design hasn’t been approved. In order to avoid redesign procedures, which can be expensive and sometimes difficult to do in reality, plastic analysis has been done. After plastic analysis, the design could be approved with the restriction on the max. preload force in the bolts 40 kN/per bolt.

The shell-to-bottom joint of hydrocarbon storage tanks is a critical location which may experience fatigue cracking and requires evaluation of the local cyclic stresses especially in the case of elevated temperature tanks. The fill/draw down cycle of the stored liquid causes low cycle fatigue near this joint and hence a fatigue evaluation is recommended. The peak alternating stress at this location, used to enter the fatigue curves is currently determined using a pseudo-elastic analysis that represents strain range due to inelastic deformations. API 650 employs beam on elastic foundation theory for this analysis. This theory is being used for tanks resting fully on earthen foundation as well as those on concrete ring wall. This paper studies the validity of using this theory for tanks with concrete ring wall foundation which are much more rigid compared to earthen foundations. Some of the difficulties in the current practice are highlighted. An alternative to the current model is presented for the determination of stresses in such tanks. The results are validated using finite element analysis. The results show that the current practice needs to be revised or rejustified in an alternative manner.

Aboveground vertical steel storage tanks use stiffener rings to prevent their shell wall from buckling under wind loading. The existing stiffener rings design rules from API 650 standard is known to be overly conservative. This study investigates the possibility of modifying the design rules by reducing the required size of the top stiffener ring to the same size as the intermediate stiffener ring. In this study, we used finite element analysis (FEA) to perform linear bifurcation analysis (LBA) and geometrically nonlinear analysis including imperfections (GNIA) to obtain failure load of modeled tanks. The buckling pressure load was obtained to ensure it is larger than the design pressure. Moreover, the effects of higher strength materials, different buckling modes, and various wind profiles were also studied to ensure the design suggested by this study is practical and universal to different situations. The results show that for cylindrical storage tanks, which only needs one intermediate stiffener ring, the size of the top stiffener ring can be set to the same size as the intermediate stiffener ring.

Introduction Many destinations promote culinary encounters. Foods and beverages, and especially how these will taste in situ, are being marketed as niche travel motivators and used in destination brand building across the globe. While initial usage of the term culinary tourism focused on experiencing exotic cultures of foreign destinations by sampling unfamiliar food and drinks, the term has expanded to embrace a range of leisure travel experiences where the aim is to locate and taste local specialities as part of a pleasurable, and hopefully notable, culinary encounter (Wolf). Long’s foundational work was central in developing the idea of culinary tourism as an active endeavor, suggesting that via consumption, individuals construct unique experiences. Ignatov and Smith’s literature review-inspired definition confirms the nature of activity as participatory, and adds consuming food production skills—from observing agriculture and local processors to visiting food markets and attending cooking schools—to culinary purchases. Despite importing almost all of its foodstuffs and beverages, including some of its water, Singapore is an acknowledged global leader in culinary tourism. Horng and Tsai note that culinary tourism conceptually implies that a transferal of “local or special knowledge and information that represent local culture and identities” (41) occurs via these experiences. This article adds the act of reading to these participatory activities and suggests that, because food writing forms an important component of Singapore’s suite of culinary tourism offerings, taste contributes to the cultural experience offered to both visitors and locals. While Singapore foodways have attracted significant scholarship (see, for instance, work by Bishop; Duruz; Huat & Rajah; Tarulevicz, Eating), Singapore food writing, like many artefacts of popular culture, has attracted less notice. Yet, this writing is an increasingly visible component of cultural production of, and about, Singapore, and performs a range of functions for locals, tourists and visitors before they arrive. Although many languages are spoken in Singapore, English is the national language (Alsagoff) and this study focuses on food writing in English. Background Tourism comprises a major part of Singapore’s economy, with recent figures detailing that food and beverage sales contribute over 10 per cent of this revenue, with spend on culinary tours and cookery classes, home wares such as tea-sets and cookbooks, food magazines and food memoirs additional to this (Singapore Government). This may be related to the fact that Singapore not only promotes food as a tourist attraction, but also actively promotes itself as an exceptional culinary destination. The Singapore Tourism Board (STB) includes food in its general information brochures and websites, and its print, television and cinema commercials (Huat and Rajah). It also mounts information-rich campaigns both abroad and inside Singapore. The 2007 ‘Singapore Seasons’ campaign, for instance, promoted Singaporean cuisine alongside films, design, books and other cultural products in London, New York and Beijing. Touring cities identified as key tourist markets in 2011, the ‘Singapore Takeout’ pop-up restaurant brought the taste of Singaporean foods into closer focus. Singaporean chefs worked with high profile locals in its kitchen in a custom-fabricated shipping container to create and demonstrate Singaporean dishes, attracting public and media interest. In country, the STB similarly actively promotes the tastes of Singaporean foods, hosting the annual World Gourmet Summit (Chaney and Ryan) and Pacific Food Expo, both attracting international culinary professionals to work alongside local leaders. The Singapore Food Festival each July is marketed to both locals and visitors. In these ways, the STB, as well as providing events for visitors, is actively urging Singaporeans to proud of their food culture and heritage, so that each Singaporean becomes a proactive ambassador of their cuisine. Singapore Food Writing Popular print guidebooks and online guides to Singapore pay significantly more attention to Singaporean food than they do for many other destinations. Sections on food in such publications discuss at relative length the taste of Singaporean food (always delicious) as well as how varied, authentic, hygienic and suited-to-all-budgets it is. These texts also recommend hawker stalls and food courts alongside cafés and restaurants (Henderson et al.), and a range of other culinary experiences such as city and farm food tours and cookery classes. This writing describes not only what can be seen or learned during these experiences, but also what foods can be sampled, and how these might taste. This focus on taste is reflected in the printed materials that greet the in-bound tourist at the airport. On a visit in October 2013, arrival banners featuring mouth-watering images of local specialities such as chicken rice and chilli crab marked the route from arrival to immigration and baggage collection. Even advertising for a bank was illustrated with photographs of luscious-looking fruits. The free maps and guidebooks available featured food-focused tours and restaurant locations, and there were also substantial free booklets dedicated solely to discussing local delicacies and their flavours, plus recommended locations to sample them. A website and free mobile app were available that contain practical information about dishes, ingredients, cookery methods, and places to eat, as well as historical and cultural information. These resources are also freely distributed to many hotels and popular tourist destinations. Alongside organising food walks, bus tours and cookery classes, the STB also recommends the work of a number of Singaporean food writers—principally prominent Singapore food bloggers, reviewers and a number of memoirists—as authentic guides to what are described as unique Singaporean flavours. The strategies at the heart of this promotion are linking advertising to useful information. At a number of food centres, for instance, STB information panels provide details about both specific dishes and Singapore’s food culture more generally (Henderson et al.). This focus is apparent at many tourist destinations, many of which are also popular local attractions. In historic Fort Canning Park, for instance, there is a recreation of Raffles’ experimental garden, established in 1822, where he grew the nutmeg, clove and other plants that were intended to form the foundation for spice plantations but were largely unsuccessful (Reisz). Today, information panels not only indicate the food plants’ names and how to grow them, but also their culinary and medicinal uses, recipes featuring them and the related food memories of famous Singaporeans. The Singapore Botanic Gardens similarly houses the Ginger Garden displaying several hundred species of ginger and information, and an Eco(-nomic/logical) Garden featuring many food plants and their stories. In Chinatown, panels mounted outside prominent heritage brands (often still quite small shops) add content to the shopping experience. A number of museums profile Singapore’s food culture in more depth. The National Museum of Singapore has a permanent Living History gallery that focuses on Singapore’s street food from the 1950s to 1970s. This display includes food-related artefacts, interactive aromatic displays of spices, films of dishes being made and eaten, and oral histories about food vendors, all supported by text panels and booklets. Here food is used to convey messages about the value of Singapore’s ethnic diversity and cross-cultural exchanges. Versions of some of these dishes can then be sampled in the museum café (Time Out Singapore). The Peranakan Museum—which profiles the unique hybrid culture of the descendants of the Chinese and South Indian traders who married local Malay women—shares this focus, with reconstructed kitchens and dining rooms, exhibits of cooking and eating utensils and displays on food’s ceremonial role in weddings and funerals all supported with significant textual information. The Chinatown Heritage Centre not only recreates food preparation areas as a vivid indicator of poor Chinese immigrants’ living conditions, but also houses The National Restaurant of Singapore, which translates this research directly into meals that recreate the heritage kopi tiam (traditional coffee shop) cuisine of Singapore in the 1930s, purposefully bringing taste into the service of education, as its descriptive menu states, “educationally delighting the palate” (Chinatown Heritage Centre). These museums recognise that shopping is a core tourist activity in Singapore (Chang; Yeung et al.). Their gift- and bookshops cater to the culinary tourist by featuring quality culinary products for sale (including, for instance, teapots and cups, teas, spices and traditional sweets, and other foods) many of which are accompanied by informative tags or brochures. At the centre of these curated, purchasable collections are a range written materials: culinary magazines, cookbooks, food histories and memoirs, as well as postcards and stationery printed with recipes. Food Magazines Locally produced food magazines cater to a range of readerships and serve to extend the culinary experience both in, and outside, Singapore. These include high-end gourmet, luxury lifestyle publications like venerable monthly Wine & Dine: The Art of Good Living, which, in in print for almost thirty years, targets an affluent readership (Wine & Dine). The magazine runs features on local dining, gourmet products and trends, as well as international epicurean locations and products. Beautifully illustrated recipes also feature, as the magazine declares, “we’ve recognised that sharing more recipes should be in the DNA of Wine & Dine’s editorial” (Wine & Dine). Appetite magazine, launched in 2006, targets the “new and emerging generation of gourmets—foodies with a discerning and cosmopolitan outlook, broad horizons and a insatiable appetite” (Edipresse Asia) and is reminiscent in much of its styling of New Zealand’s award-winning Cuisine magazine. Its focus is to present a fresh approach to both cooking at home and dining out, as readers are invited to “Whip up the perfect soufflé or feast with us at the finest restaurants in Singapore and around the region” (Edipresse Asia). Chefs from leading local restaurants are interviewed, and the voices of “fellow foodies and industry watchers” offer an “insider track” on food-related news: “what’s good and what’s new” (Edipresse Asia). In between these publications sits Epicure: Life’s Refinements, which features local dishes, chefs, and restaurants as well as an overseas travel section and a food memories column by a featured author. Locally available ingredients are also highlighted, such as abalone (Cheng) and an interesting range of mushrooms (Epicure). While there is a focus on an epicurean experience, this is presented slightly more casually than in Wine & Dine. Food & Travel focuses more on home cookery, but each issue also includes reviews of Singapore restaurants. The bimonthly bilingual (Chinese and English) Gourmet Living features recipes alongside a notable focus on food culture—with food history columns, restaurant reviews and profiles of celebrated chefs. An extensive range of imported international food magazines are also available, with those from nearby Malaysia and Indonesia regularly including articles on Singapore. Cookbooks These magazines all include reviews of cookery books including Singaporean examples – and some feature other food writing such as food histories, memoirs and blogs. These reviews draw attention to how many Singaporean cookbooks include a focus on food history alongside recipes. Cookery teacher Yee Soo Leong’s 1976 Singaporean Cooking was an early example of cookbook as heritage preservation. This 1976 book takes an unusual view of ‘Singaporean’ flavours. Beginning with sweet foods—Nonya/Singaporean and western cakes, biscuits, pies, pastries, bread, desserts and icings—it also focuses on both Singaporean and Western dishes. This text is also unusual as there are only 6 lines of direct authorial address in the author’s acknowledgements section. Expatriate food writer Wendy Hutton’s Singapore Food, first published in 1979, reprinted many times after and revised in 2007, has long been recognised as one of the most authoritative titles on Singapore’s food heritage. Providing an socio-historical map of Singapore’s culinary traditions, some one third of the first edition was devoted to information about Singaporean multi-cultural food history, including detailed profiles of a number of home cooks alongside its recipes. Published in 1980, Kenneth Mitchell’s A Taste of Singapore is clearly aimed at a foreign readership, noting the variety of foods available due to the racial origins of its inhabitants. The more modest, but equally educational in intent, Hawkers Flavour: A Guide to Hawkers Gourmet in Malaysia and Singapore (in its fourth printing in 1998) contains a detailed introductory essay outlining local food culture, favourite foods and drinks and times these might be served, festivals and festive foods, Indian, Indian Muslim, Chinese, Nyonya (Chinese-Malay), Malay and Halal foods and customs, followed with a selection of recipes from each. More contemporary examples of such information-rich cookbooks, such as those published in the frequently reprinted Periplus Mini Cookbook series, are sold at tourist attractions. Each of these modestly priced, 64-page, mouthwateringly illustrated booklets offer framing information, such as about a specific food culture as in the Nonya kitchen in Nonya Favourites (Boi), and explanatory glossaries of ingredients, as in Homestyle Malay Cooking (Jelani). Most recipes include a boxed paragraph detailing cookery or ingredient information that adds cultural nuance, as well as trying to describe tastes that the (obviously foreign) intended reader may not have encountered. Malaysian-born Violet Oon, who has been called the Julia Child of Singapore (Bergman), writes for both local and visiting readers. The FOOD Paper, published monthly for a decade from January 1987 was, she has stated, then “Singapore’s only monthly publication dedicated to the CSF—Certified Singapore Foodie” (Oon, Violet Oon Cooks 7). Under its auspices, Oon promoted her version of Singaporean cuisine to both locals and visitors, as well as running cookery classes and culinary events, hosting her own television cooking series on the Singapore Broadcasting Corporation, and touring internationally for the STB as a ‘Singapore Food Ambassador’ (Ahmad; Kraal). Taking this representation of flavor further, Oon has also produced a branded range of curry powders, spices, and biscuits, and set up a number of food outlets. Her first cookbook, World Peranakan Cookbook, was published in 1978. Her Singapore: 101 Meals of 1986 was commissioned by the STB, then known as the Singapore Tourist Promotion Board. Violet Oon Cooks, a compilation of recipes from The FOOD Paper, published in 1992, attracted a range of major international as well as Singaporean food sponsors, and her Timeless Recipes, published in 1997, similarly aimed to show how manufactured products could be incorporated into classic Singaporean dishes cooked at home. In 1998, Oon produced A Singapore Family Cookbook featuring 100 dishes. Many were from Nonya cuisine and her following books continued to focus on preserving heritage Singaporean recipes, as do a number of other nationally-cuisine focused collections such as Joyceline Tully and Christopher Tan’s Heritage Feasts: A Collection of Singapore Family Recipes. Sylvia Tan’s Singapore Heritage Food: Yesterday’s Recipes for Today’s Cooks, published in 2004, provides “a tentative account of Singapore’s food history” (5). It does this by mapping the various taste profiles of six thematically-arranged chronologically-overlapping sections, from the heritage of British colonialism, to the uptake of American and Russia foods in the Snackbar era of the 1960s and the use of convenience flavoring ingredients such as curry pastes, sauces, dried and frozen supermarket products from the 1970s. Other Volumes Other food-themed volumes focus on specific historical periods. Cecilia Leong-Salobir’s Food Culture in Colonial Asia: A Taste of Empire discusses the “unique hybrid” (1) cuisine of British expatriates in Singapore from 1858 to 1963. In 2009, the National Museum of Singapore produced the moving Wong Hong Suen’s Wartime Kitchen: Food and Eating in Singapore 1942–1950. This details the resilience and adaptability of both diners and cooks during the Japanese Occupation and in post-war Singapore, when shortages stimulated creativity. There is a centenary history of the Cold Storage company which shipped frozen foods all over south east Asia (Boon) and location-based studies such as Annette Tan’s Savour Chinatown: Stories Memories & Recipes. Tan interviewed hawkers, chefs and restaurant owners, working from this information to write both the book’s recipes and reflect on Chinatown’s culinary history. Food culture also features in (although it is not the main focus) more general book-length studies such as educational texts such as Chew Yen Fook’s The Magic of Singapore and Melanie Guile’s Culture in Singapore (2000). Works that navigate both spaces (of Singaporean culture more generally and its foodways) such Lily Kong’s Singapore Hawker Centres: People, Places, Food, provide an consistent narrative of food in Singapore, stressing its multicultural flavours that can be enjoyed from eateries ranging from hawker stalls to high-end restaurants that, interestingly, that agrees with that promulgated in the food writing discussed above. Food Memoirs and Blogs Many of these narratives include personal material, drawing on the author’s own food experiences and taste memories. This approach is fully developed in the food memoir, a growing sub-genre of Singapore food writing. While memoirs by expatriate Singaporeans such as Cheryl Lu-Lien Tan’s A Tiger in the Kitchen: A Memoir of Food and Family, produced by major publisher Hyperion in New York, has attracted considerable international attention, it presents a story of Singapore cuisine that agrees with such locally produced texts as television chef and food writer Terry Tan’s Stir-fried and Not Shaken: A Nostalgic Trip Down Singapore’s Memory Lane and the food memoir of the Singaporean chef credited with introducing fine Malay dining to Singapore, Aziza Ali’s Sambal Days, Kampong Cuisine, published in Singapore in 2013 with the support of the National Heritage Board. All these memoirs are currently available in Singapore in both bookshops and a number of museums and other attractions. While underscoring the historical and cultural value of these foods, all describe the unique flavours of Singaporean cuisine and its deliciousness. A number of prominent Singapore food bloggers are featured in general guidebooks and promoted by the STB as useful resources to dining out in Singapore. One of the most prominent of these is Leslie Tay, a medical doctor and “passionate foodie” (Knipp) whose awardwinning ieatŸishootŸipost is currently attracting some 90,000 unique visitors every month and has had over 20,000 million hits since its launch in 2006. An online diary of Tay’s visits to hundreds of Singaporean hawker stalls, it includes descriptions and photographs of meals consumed, creating accumulative oral culinary histories of these dishes and those who prepared them. These narratives have been reorganised and reshaped in Tay’s first book The End of Char Kway Teow and Other Hawker Mysteries, where each chapter tells the story of one particular dish, including recommended hawker stalls where it can be enjoyed. Ladyironchef.com is a popular food and travel site that began as a blog in 2007. An edited collection of reviews of eateries and travel information, many by the editor himself, the site features lists of, for example, the best cafes (LadyIronChef “Best Cafes”), eateries at the airport (LadyIronChef “Guide to Dining”), and hawker stalls (Lim). While attesting to the cultural value of these foods, many articles also discuss flavour, as in Lim’s musings on: ‘how good can chicken on rice taste? … The glistening grains of rice perfumed by fresh chicken stock and a whiff of ginger is so good you can even eat it on its own’. Conclusion Recent Singapore food publishing reflects this focus on taste. Tay’s publisher, Epigram, growing Singaporean food list includes the recently released Heritage Cookbooks Series. This highlights specialist Singaporean recipes and cookery techniques, with the stated aim of preserving tastes and foodways that continue to influence Singaporean food culture today. Volumes published to date on Peranakan, South Indian, Cantonese, Eurasian, and Teochew (from the Chaoshan region in the east of China’s Guangdong province) cuisines offer both cultural and practical guides to the quintessential dishes and flavours of each cuisine, featuring simple family dishes alongside more elaborate special occasion meals. In common with the food writing discussed above, the books in this series, although dealing with very different styles of cookery, contribute to an overall impression of the taste of Singapore food that is highly consistent and extremely persuasive. This food writing narrates that Singapore has a delicious as well as distinctive and interesting food culture that plays a significant role in Singaporean life both currently and historically. It also posits that this food culture is, at the same time, easily accessible and also worthy of detailed consideration and discussion. In this way, this food writing makes a contribution to both local and visitors’ appreciation of Singaporean food culture. References Ahmad, Nureza. “Violet Oon.” Singapore Infopedia: An Electronic Encyclopedia on Singapore’s History, Culture, People and Events (2004). 22 Nov. 2013 ‹http://infopedia.nl.sg/articles/SIP_459_2005-01-14.html?s=Violet%20Oon›.Ali, Aziza. Sambal Days, Kampong Cuisine. Singapore: Ate Ideas, 2013. Alsagoff, Lubna. “English in Singapore: Culture, capital and identity in linguistic variation”. World Englishes 29.3 (2010): 336–48.Bergman, Justin. “Restaurant Report: Violet Oon’s Kitchen in Singapore.” New York Times (13 March 2013). 21 Nov. 2013 ‹http://www.nytimes.com/2013/03/17/travel/violet-oons-kitchen-singapore-restaurant-report.html?_r=0›. Bishop, Peter. “Eating in the Contact Zone: Singapore Foodscape and Cosmopolitan Timespace.” Continuum: Journal of Media & Cultural Studies 25.5 (2011): 637–652. Boi, Lee Geok. Nonya Favourites. Singapore: Periplus Editions, 2001. Boon, Goh Chor. Serving Singapore: A Hundred Years of Cold Storage 1903-2003. Singapore: Cold Storage Pty. Ltd., 2003. Chaney, Stephen, and Chris Ryan. “Analyzing the Evolution of Singapore’s World Gourmet Summit: An Example of Gastronomic Tourism.” International Journal of Hospitality Management 31.2 (2012): 309–18. Chang, T. C. “Local Uniqueness in the Global Village: Heritage Tourism in Singapore.” The Professional Geographer 51.1 (1999): 91–103. Cheng, Tiong Li. “Royal Repast.” Epicure: Life’s Refinements January (2012): 94–6. Chinatown Heritage Centre. National Restaurant of Singapore. (12 Nov. 2012). 21 Nov. 2013 ‹http://www.yoursingapore.com›.Duruz, Jean. “Living in Singapore, Travelling to Hong Kong, Remembering Australia …: Intersections of Food and Place.” Journal of Australian Studies 87 (2006): 101–15. -----. “From Malacca to Adelaide: Fragments Towards a Biography of Cooking, Yearning and Laksa.” Food and Foodways in Asia: Resource, Tradition and Cooking. Eds. Sidney C.H. Cheung, and Tan Chee-Beng. London: Routledge, 2007: 183–200. -----. “Tastes of Hybrid Belonging: Following the Laksa Trail in Katong, Singapore.” Continuum: Journal of Media & Cultural Studies 25.5 (2011): 605–18. Edipresse Asia Appetite (2013). 22 Nov. 2013 ‹http://www.edipresseasia.com/magazines.php?MagID=SGAPPETITE›. Epicure. “Mushroom Goodness.” Epicure: Life’s Refinements January (2012): 72–4. Epicure: Life’s Refinements. (2013) 1 Jan. 2014 ‹http://www.epicureasia.com›. Food & Travel. Singapore: Regent Media. 1 Jan. 2014 ‹http://www.regentmedia.sg/publications_food&travel.shtml›. Fook, Chew Yen. The Magic of Singapore. London: New Holland, 2000. Guile, Melanie. Culture in Singapore. Port Melbourne: Heinemann/Harcourt Education Australia, 2003. Hawkers Flavour: A Guide to Hawkers Gourmet in Malaysia and Singapore. Kuala Lumpur: S. Abdul Majeed & Co., 1998. Henderson, Joan C., Ong Si Yun, Priscilla Poon, and Xu Biwei. “Hawker Centres as Tourist Attractions: The Case of Singapore.” International Journal of Hospitality Management 31.3 (2012): 849–55. Horng, Jeou-Shyan, and Chen-Tsang (Simon) Tsai. “Culinary Tourism Strategic Development: An Asia‐Pacific Perspective.” International Journal of Tourism Research 14 (2011): 40–55. Huat, Chua Beng, and Ananda Rajah. “Hybridity, Ethnicity and Food in Singapore.” Changing Chinese Foodways in Asia. Eds. David Y. H. Wu, and Chee Beng Tan. Hong Kong: The Chinese University of Hong Kong, Hong Kong, 2001: 161–98. Hutton, Wendy. Singapore Food. Singapore: Martin Cavendish, 1989/2007. Ignatov, Elena, and Stephen Smith. “Segmenting Canadian Culinary Tourists.” Current Issues in Tourism 9.3 (2006): 235–55. Jelani, Rohani. Homestyle Malay Cooking. Singapore: Periplus Editions, 2003. Knipp, Peter A. “Foreword: An Amazing Labour of Love.” The End of Char Kway Teow and Other Hawker Mysteries. Leslie Tay. Singapore: Epigram Books, 2010. viii–ix. Kong, Lily. Singapore Hawker Centres: People, Places, Food. Singapore: National Environment Agency, 2007 Kraal, David. “One and Only Violet Oon.” The Straits Times 20 January (1999). 1 Nov 2012 ‹http://www.straitstimes.com› LadyIronChef. “Best Cafes in Singapore.” ladyironchef.com (31 Mar. 2011). 21 Feb. 2014 ‹http://www.ladyironchef.com/2011/03/best-cafes-singapore› -----. “Guide to Dining at Changi Airport: 20 Places to Eat.” ladyironchef.com (10 Mar. 2014) 10 Mar. 2014 ‹http://www.ladyironchef.com/author/ladyironchef› Leong-Salobir, Cecilia. Food Culture in Colonial Asia: A Taste of Empire. Abingdon UK: Routledge, 2011. Lim, Sarah. “10 of the Best Singapore Hawker Food.” (14 Oct. 2013). 21 Feb. 2014 ‹http://www.ladyironchef.com/2013/10/best-singapore-hawker-food›. Long, Lucy M. “Culinary Tourism: A Folkloristic Perspective of Eating and Otherness.” Southern Folklore 55.2 (1998): 181–204. Mitchell, Kenneth, ed. A Taste of Singapore. Hong Kong: Four Corners Publishing Co. (Far East) Ltd. in association with South China Morning Post, 1980. Oon, Violet. World Peranakan Cookbook. Singapore: Times Periodicals, 1978. -----. Singapore: 101 Meals. Singapore: Singapore Tourist Promotion Board, 1986. -----. Violet Oon Cooks. Singapore: Ultra Violet, 1992. -----. Timeless Recipes. Singapore: International Enterprise Singapore, 1997. -----. A Singapore Family Cookbook. Singapore: Pen International, 1998. Reisz, Emma. “City as Garden: Shared Space in the Urban Botanic Gardens of Singapore and Malaysia, 1786–2000.” Postcolonial Urbanism: Southeast Asian Cities and Global Processes. Eds. Ryan Bishop, John Phillips, and Yeo Wei Wei. New York: Routledge, 2003: 123–48. Singapore Government. Singapore Annual Report on Tourism Statistics. Singapore: Singapore Government, 2012. Suen, Wong Hong. Wartime Kitchen: Food and Eating in Singapore 1942-1950. Singapore: Editions Didier Millet & National Museum of Singapore, 2009. Tan, Annette. Savour Chinatown: Stories, Memories & Recipes. Singapore: Ate Ideas, 2012. Tan, Cheryl Lu-Lien. A Tiger in the Kitchen: A Memoir of Food and Family. New York: Hyperion, 2011. Tan, Sylvia. Singapore Heritage Food: Yesterday’s Recipes for Today’s Cooks. Singapore: Landmark Books, 2004. Tan, Terry. Stir-Fried and Not Shaken: A Nostalgic Trip Down Singapore’s Memory Lane. Singapore: Monsoon, 2009. Tarulevicz, Nicole. Eating Her Curries and Kway: A Cultural History of Food in Singapore. Champaign, IL: U of Illinois P, 2013. Tay, Leslie. ieat·ishoot·ipost [blog] (2013) 21 Nov. 2013 ‹http://www.ieatishootipost.sg›. ---. The End of Char Kway Teow and Other Hawker Mysteries. Singapore: Epigram Books, 2010. Time Out Singapore. “Food for Thought (National Museum).” Time Out Singapore 8 July (2013). 11 Nov. 2013 ‹http://www.timeoutsingapore.com/restaurants/asian/food-for-thought-national-museum›. Tully, Joyceline, and Tan, Christopher. Heritage Feasts: A Collection of Singapore Family Recipes. Singapore: Miele/Ate Media, 2010. Wine & Dine: The Art of Good Living (Nov. 2013). 19 Nov. 2013 ‹http://www.wineanddine.com.sg›. Wine & Dine. “About Us: The Living Legacy.” Wine & Dine (Nov. 2013). 19 Nov. 2013 ‹http://www.wineanddine.com.sg/about-us› Wolf, E. “Culinary Tourism: A Tasty Economic Proposition.” (2002) 23 Nov. 2011 ‹http://www.culinary tourism.org›.Yeong, Yee Soo. Singapore Cooking. Singapore: Eastern Universities P, c.1976. Yeung, Sylvester, James Wong, and Edmond Ko. “Preferred Shopping Destination: Hong Kong Versus Singapore.” International Journal of Tourism Research 6.2 (2004): 85–96. Acknowledgements Research to complete this article was supported by Central Queensland University, Australia, under its Outside Studies Program (OSPRO) and Learning and Teaching Education Research Centre (LTERC). An earlier version of part of this article was presented at the 2nd Australasian Regional Food Networks and Cultures Conference, in the Barossa Valley in South Australia, Australia, 11–14 November 2012. The delegates of that conference and expert reviewers of this article offered some excellent suggestions regarding strengthening this article and their advice was much appreciated. All errors are, of course, my own.