Relevant bibliographies by topics / Positive displacement compressor

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
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Academic literature on the topic 'Positive displacement compressor'

Author: Grafiati
Published: 19 February 2023

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Journal articles on the topic "Positive displacement compressor"

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Sun, Jian, Bin Peng, and Bingguo Zhu. "Performance Analysis and Test Research of PEMFC Oil-Free Positive Displacement Compressor for Vehicle." Energies 14, no. 21 (November 4, 2021): 7329. http://dx.doi.org/10.3390/en14217329.

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In order to study the matching characteristics of the positive displacement air compressor and the PEMFC (proton exchange membrane fuel cells), air supply subsystem, the basic operating performance parameters of the scroll and single-screw air compressors were analyzed with the focus on the oil-free double-wrap scroll compressor. According to the thermodynamic model and three-dimensional unsteady-state numerical simulation, the variation of the temperature, pressure, and velocity was obtained. Besides, under the rated operating condition of the compressor, the inlet and outlet mass flow rate of the fluid in the working chamber with the orbiting angle of the crank was achieved. Based on the built test platform, the actual working process of scroll and screw compressors was analyzed. This study indicates that the volume flow can be significantly increased by improving the speed of the positive displacement compressor. Based on the experimental measurement, when the height of the scroll tooth of the scroll compressor increases by 5 mm, the volume flow of the prototype SC2 increases by 0.17 m3/min and the exhaust temperature is reduced by 13 °C at the rated speed.
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Shcherba, V. E., A. V. Zanin, and E. A. Pavlyuchenko. "Analysis of Liquid Piston Compressibility in the Two-Stage Hybrid Positive-Displacement Machine." E3S Web of Conferences 320 (2021): 04001. http://dx.doi.org/10.1051/e3sconf/202132004001.

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The effect of liquid compressibility in the two-stage piston hybrid positive-displacement machine with a liquid piston was considered. Based on the volume conservation equation, we developed a calculus methodology for the liquid compressibility during gas compression in the second stage of the compressor section. A numerical experiment made it possible to establish that some parameters have the greatest effect on the relative decrease in the height and velocity of the liquid layer. These parameters are the degree of pressure ratio; pipeline length; the polytropic index of the compression; the number of crankshaft revolutions. We found that the relative decrease in the liquid layer height is within 1 %, and the relative decrease in the liquid piston velocity is within 5 %. The paper analyses the liquid piston compressibility influence on the thermodynamic efficiency of the compression process and compressor performance.
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Mimmi, G., and P. Pennacchi. "Analytical model of a particular type of positive displacement blower." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 213, no. 5 (May 1, 1999): 517–26. http://dx.doi.org/10.1243/0954406991522743.

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Many papers exist in the literature that deal with the twin-screw compressor. This usually has two different rotors, a male and a female, and is commonly used to produce compressed gas for industrial uses. However, a different type of positive displacement rotary compressor with two screws is sometimes used, one of its typical applications being in car engine supercharging. The present paper deals with the latter type, which is defined as a two-screw blower. This blower has two identical helical rotors, each with three lobes. The kinematics and the geometry of the rotors are analysed here, and a complete mathematical model for the rotor is defined. Moreover, different possible shapes of the rotors, depending on the design parameters, are analysed and the limitations in the choice of the design parameters are presented. Finally, an analysis of the theoretical specific slipping of the rotors is presented, showing which zones of the profile are the most stressed. This model will be useful for further studies on rotor pressure loads and blower dynamics.
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Willie, J., S. W. Yonkers, P. X. Huang, and R. B. Ganatra. "Use of CFD to optimize the design of a shunt pulsation trap (SPT) used for noise and vibration mitigation in oil free screw compressors." IOP Conference Series: Materials Science and Engineering 1267, no. 1 (November 1, 2022): 012017. http://dx.doi.org/10.1088/1757-899x/1267/1/012017.

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Noise and vibration are problems that are inherent in screw compressors and other Positive Displacement (PD)Machines. This problem is driven partly by the lobe passing frequencies inside these machines that are generated due to the meshing between the gate and main rotors teeth. Because these compressors are operated over a wide speed range and at various loads they usually run at off-design conditions leading to either over or under-compression. In both scenarios, the pressure within the compressor always changes rapidly to match the discharge or process pressure when the discharge opens thus leading to pulsation and noise. To ensure that the compressor is operated without over and or under compression, which also negatively affects the compressor efficiency Hi-Bar Blowers, Inc developed a Shunt Pulsation Trap (SPT) that will contain and reduce the pulsation inside the compressor cavities thus eliminating the use of a silencer at the inlet and the discharge. During the SPT development the CVS Silo King (SKL 1100) compressor was selected for benchmarking this technology. CFD was used extensively to simulate the SKL 1100 without and with the SPT integrated, which allowed the SPT design to be optimized. This paper will present the results obtained to demonstrate that this technology has the potential to eliminate over and under compression while at the same time leading to energy savings and reducing the compressor footprint and the noise and vibration that are commonplace in screw compressors.
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Basha, Nausheen, Ahmed Kovacevic, and Sham Rane. "Analysis of Oil-Injected Twin-Screw Compressor with Multiphase Flow Models." Designs 3, no. 4 (December 16, 2019): 54. http://dx.doi.org/10.3390/designs3040054.

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Growing demands for energy are motivating researchers to conduct in-depth analysis of positive displacement machines such as oil-injected screw compressors which are frequently used in industrial applications like refrigeration, oil and gas and air compression. The performance of these machines is strongly dependent on the oil injection. Optimisation of oil has a great energy saving potential by both increasing efficiency and reducing other impacts on the environment. Therefore, a three-dimensional, transient computational fluid dynamics study of oil injection in a twin-screw compressor is conducted in this research. This study explores pseudo single-fluid multiphase (SFM) models of VOF (Volume of Fluid) and a mixture for their capability to predict the performance of the oil-injected twin screw compressor and compare this with the experimental values. SCORGTM (Screw Compressor Rotor Grid Generator) is used to generate numerical grids for unstructured solver Fluent with the special interface developed to facilitate user defined nodal displacement (UDND). The performance predictions with both VOF and mixture models provide accurate values for power consumption and flow rates with low deviation between computational fluid dynamics (CFD) and the experiment at 6000 RPM and 7.0 bar discharge pressure. In addition, the study reflects on differences in predicting oil distribution with VOF, mixture and Eulerian-Eulerian two-fluid models. Overall, this study provides an insight into multiphase flow-modelling techniques available for oil-injected twin-screw compressors comprehensively accounting for the details of oil distribution in the compression chamber and integral compressor performance.
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Lu, Kui, Truong H. Phung, and Ibrahim A. Sultan. "On the Design of a Class of Rotary Compressors Using Bayesian Optimization." Machines 9, no. 10 (September 29, 2021): 219. http://dx.doi.org/10.3390/machines9100219.

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The optimization process of compressors is usually regarded as a ‘black-box’ problem, in which the mathematical form underlying the relationship between design parameters and the design objective is impractical and costly to be obtained. To solve the ‘black-box’ problem, Bayesian optimization has been proven as an accurate and efficient method. However, the application of such a method in the design of compressors is rarely discussed, particularly no work has been reported in terms of the positive displacement type compressor. Therefore, this paper aims to introduce the Bayesian optimization to the design of positive displacement compressors through the optimization process of the novel limaçon compressor. In this paper, a two-stage optimization process is presented, in which the first stage optimizes the geometric parameters as per design requirements and the second stage focuses on revealing an optimum setting of port geometries that improves machine performance. A numerical illustration is offered to prove the validity of the presented approach.
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Huang, P. X., S. Yonkers, and J. Willie. "A Novel Screw Compressor with a Shunt Enhanced Compression and Pulsation Trap (SECAPT)." IOP Conference Series: Materials Science and Engineering 1267, no. 1 (November 1, 2022): 012019. http://dx.doi.org/10.1088/1757-899x/1267/1/012019.

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Some positive displacement (PD) compressors are equipped with automatic discharge valves such as reed valves that open automatically whenever the cavity pressure is slightly larger than the outlet pressure to deal effectively with varying pressure ratio applications. Screw compressors today do not have such valves, resulting in off-design conditions known as the under-compression or over-compression when the cavity pressure at discharge is deviating from the outlet pressure. Compressor efficiency suffers and pulsation/noise becomes worse under these conditions. Some type of controls are desired such as a discharge pulsation dampener or a variable volume ratio (often called variable Vi) slide valve design to lessen or cure the discharge pressure mismatch problems. Injecting gas vapor into a screw compressor cavity during internal compression phase has been known to be beneficial in enhancing compressor performance and has been widely used in HVAC&R industry known as the Economizer. However, the underlining principle of the Economizer has thus far not been explored for optimizing compression schemes of a screw compressor in general. This paper introduces a self-sensing and self-correcting compression process that can be “derived or deduced” from the Perfect Gas Law by optimizing for multiple design criteria such as compressor efficiency, pulsation/noise abatement, and cost and footprint reduction for a screw operating over a wide range of pressures. The scheme, called SECAPT (Shunt Enhanced Compression And Pulsation Trap), is then investigated and optimized numerically by a new CFD code for one industrial case: a bulk truck loading application where compressor pressure varies from no pressure rise to maximum load. The numerical simulations illustrate that SECAPT is tentatively capable of achieving multiple targets as theorized.
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Kubo, Masahiro, Noritsugu Kawashima, and Hitoshi Marumo. "Dynamic Analysis of Plain Bearings in a Positive-Displacement Rotary Compressor." A S L E Transactions 30, no. 3 (January 1987): 310–15. http://dx.doi.org/10.1080/05698198708981762.

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Tanveer, M. Mohsin, and Craig R. Bradshaw. "Quantitative and qualitative evaluation of various positive-displacement compressor modeling platforms." International Journal of Refrigeration 119 (November 2020): 48–63. http://dx.doi.org/10.1016/j.ijrefrig.2020.07.009.

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Song, Yan Dong. "Secondary Developing and Finite Element Analysis on Screw Compressor of Automotive Air Conditioning." Applied Mechanics and Materials 467 (December 2013): 492–95. http://dx.doi.org/10.4028/www.scientific.net/amm.467.492.

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The three-screw compressor is a special type of positive displacement compressors that has two or more intermeshing screws rotating axially to deliver fluids. Three-screw compressor depend mainly on master-slave screw meshing with each other forming seal cavity so as to delivery liquid from the suction to the outlet. So it is important to design the screw profile accurately to obtain a high volumetric efficiency of the screw compressor. Through the central rotor and idler rotors three-dimensional model, we can directly obtain the central rotor and idler rotors law Section Surface contour and longitudinal section Surface contour. At the same time, this method can also provide a reference model for access complex surfaces checking template.
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Dissertations / Theses on the topic "Positive displacement compressor"

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THEOBALD, WILLIAN FELIPE. "ANALYSIS OF AN INNOVATIVE POSITIVE DISPLACEMENT ROTARY COMPRESSOR." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2013. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=37193@1.

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A presente dissertação trata do projeto, construção e ensaio preliminar de um novo modelo do compressor Kopelrot. É uma máquina de deslocamento positivo baseada em seis patentes depositadas desde 1998. Esta tecnologia está em desenvolvimento há aproximadamente 8 anos, tendo gerado artigos e dissertações, assim como a construção de dois protótipos. É apresentada, inicialmente, uma revisão dos trabalhos publicados sobre a tecnologia Kopelrot. Foram construídos junto ao novo modelo de compressor Kopelrot um novo sistema de acionamento e uma base para a fixação de ambos a um motor elétrico. Durante a elaboração dos desenhos foram realizadas simulações preliminares da geometria para definir a fabricação de algumas peças importantes. A base permite regular a excentricidade entre os eixos de centro do compressor e do sistema de acionamento e, dessa forma, variar a vazão volumétrica do compressor. Simulou-se a variação de volume no interior da câmara com o conjunto compressor Kopelrot/Sistema de acionamento, ajustado para 5 excentricidades diferentes, a fim de mapear o comportamento do Kopelrot quando sua capacidade é variada, deslocando-se os eixos de centro do compressor e do sistema de acionamento. Para as excentricidades escolhidas, foram calculadas, a partir de modelo termodinâmico simplificado, as variações de pressão, temperatura e massa no interior da câmara do compressor. Valores globais de potência consumida e eficiência volumétrica também foram calculados. Durante o funcionamento do protótipo identificaram-se alguns problemas tipicamente encontrados em tecnologias inovadoras. Devido a esses problemas, não foi possível a realização dos testes do compressor operando em condições normais de pressão.
The present dissertation addresses the design, construction, simulation and preliminary tests of an innovative positive displacement rotary compressor. A review is presented on the previous works, papers and dissertations, based on this new this new Kopelrot technology. A new prototype, employing a new driving system, was manufactured. The main feature of the machine is that, by adjusting the eccentricity between compressor cylinder and driving mechanisms axis, a variable capacity device is obtained. Design, manufacturing and assembly of components and subsystems of the compressor are presented in detail. Design data of the compressor allowed for a simple thermodynamic simulation model to be developed. Main conclusions of the simulation are that a full positive displacement compression cycle can be attained with the Kopelrot technology and that use of discharge and suction valves is required in order to have the compressor operating under different conditions.
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Lu, Kui. "Design and optimisation of the limaçon rotary compressor." Thesis, Federation University Australia, 2022. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/187200.

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The limaçon positive displacement machine is characterised by its internal geometry and unique mechanical motion; both based on a mathematical curve known as the limaçon of Pascal. The limaçon technology offers many advantages, such as compact size and double‐acting functionality, and its great potential for fluid processing applications has been proven by a number of patents and innovative designs in engines, expanders, and pumps. However, no commercial application of the limaçon technology in the field of positive displacement compressors has been reported in the literature. This could be attributed to the fact that the potential of the limaçon technology for gas compression has not been established as yet. The process of establishing potential is necessary before funds and resources are dedicated to investing in prototyping and testing. This process entails a considerable amount of modelling, coding and analysis as one must ensure the embodiment is geometrically capable of delivering suction and compression strokes, ports can be arranged to support the workings of these strokes, a number of measurable parameters can be identified as impacting compressor performance and it is possible to calculate a set of parameters which optimise this performance. To achieve this objective, a comprehensive mathematical model of a limaçon machine, implemented as a compressor,was first developed. The model, which is multi‐physical in nature, spans such domains as kinematics, fluid dynamics, characteristics of the port flow, internal leakage due to seal vibration, dynamics of the discharge valve, and thermodynamics. Subsequently, the simulation of the model has been performed to numerically study the operational characteristics of the limaçon compressor and to investigate the effect of various parameters on the compressor performance. It was found that the increase in the operating speed and pressure ratio would lead to negative effects on machine performance, especially on volumetric efficiency. Additionally, the results of simulations indicated that the level of fluid over‐compression is influenced by the characteristics of the discharge valve. To ensure the suitability of limaçon technology for use in positive displacement compressors, a study was undertaken to determine whether such an embodiment lent itself to optimisation efforts. For this purpose, the thorough mathematical model which has been developed to simulate compressor workings was then used for optimisation purposes whereby a Bayesian optimisation procedure was applied. The optimisation procedure was conducted in a two‐stage fashion where the first stage optimises the machine dimensions to meet volumetric requirements specified by the designer; and the second stage focuses on revealing the optimum combination of port geometries that improves machine performance. A numerical illustration was presented to prove the validity of the presented approach, and the results show that considerable improvements in the isentropic and volumetric efficiencies can be attained. Moreover, the optimised design was tested under different operating speeds and pressure ratios to investigate its robustness. It was found that the optimised design can exhibit relatively stable performance when the working conditions vary within a small bandwidth around that used in the optimisation procedure. The limaçon technology has three embodiments, namely the limaçon‐to‐limaçon (L2L), the limaçon‐to‐circular, and the circolimaçon. The circolimaçon embodiment features using circular arcs, rather than limaçon curves, to develop profiles for the rotor and housing. This embodiment simplifies the manufacturing process and reduces the production cost associated with producing a limaçon technology. A feasibility study of the circolimaçon embodiment was conducted by comparing its performance with that of the L2L type device. The machine dimensions and port geometries obtained from the optimisation procedure were used in the comparative study. A nonlinear three‐degree of freedom model was presented to describe the dynamic behaviour of the apex seal during the machine operation. Additionally, the leakage through the seal‐housing gap was formulated by considering the inertia and viscous effects of the flow. The results from the case study suggest that the circolimaçon embodiment exhibits comparable performance to the L2L‐type machine, despite having more significant seal vibrations. Moreover, it was also discovered that the circolimaçon compressor with a small capacity undergoes a lower level of seal dynamics, indicating better machine reliability.
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(6251672), Cai S. Rohleder. "Experimental Analysis of Positive Displacement Compressors for Refrigerator Freezer and Air Conditioning Application." Thesis, 2019.

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Vapor compression cycles are the most common method used to provide cooling to environments. In the residential area, refrigerator/freezers as well as air conditioners/heat pumps almost exclusively use vapor compression cycles. The driving force behind a vapor compression cycle is the compressor, where a variety of compressor types are used in the same application. While reciprocating compressors are found in the majority of refrigerator/freezers, scroll compressors are predominantly used in residential air conditioners. Yet other compressors have emerged as replacements due to increased efficiency. A R134a oil-free prototype scroll compressor and a R134a reciprocating compressor are operated in a hot-gas bypass test stand under refrigerator/freezer conditions to compare performance. Additionally, a R407C scroll compressor and a R410A rotary compressor are operated in a compressor calorimeter under air conditioning/heat pump conditions to compare performance. Experimental results show that the reciprocating compressor far outperforms the prototype scroll compressor in the refrigerator/freezer application, while the performance between the scroll and rotary compressors are almost equal in the air conditioning application.
Pressure fluctuation at compressor discharge is also measured in the compressor calorimeter to determine feasibility of applying a novel muffling design to air conditioning compressors, although it was found that traditional muffling methods currently used are effective to a degree such that this new method is unwarranted. Data from the compressor calorimeter is also used to investigate the accuracy of the AHRI 540 10-Coefficient Correlation compressor map in predicting performance both inside and outside the tested operating conditions. The AHRI 10-Coefficient Correlation achieves high accuracy inside tested operating conditions but is inept in extrapolating performance, where other map correlations are more accurate.
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Aboel, Hassan Muhammed Ameen. "Rotordynamics of Twin-Screw Pumps." Thesis, 2013. http://hdl.handle.net/1969.1/149281.

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Twin-screw pumps are positive displacement machines. Two meshing screws connected by timing gears convey the fluid trapped in the screw chambers axially from suction to discharge and force it out against the back pressure. Because of the screw geometry, the circumferential pressure field around the screws is not balanced, resulting in net dynamic and static pressures applied on the rotors. The research work presented here aims at building and verifying a model to predict both: (1) the exciting lateral hydrodynamic forces produced by the unbalanced pressure field, and (2) the rotor response due to those forces. The model rests on the screw pump hydraulic models for predicting the pressure in the screw chambers as a function of the discharge pressure. These models are extended to predict the steady state dynamic pressure field as a function of the rotational angle of the rotor. The dynamic force resulting from the dynamic pressure field is calculated and applied to the rotor as a set of super-synchronous periodic forces. The structural model of the screw, although nonsymmetrical, was found to be accurately represented by an axisymmetric equivalent structure. The rotor response to the dynamic super-synchronous forces is calculated to predict the pump rotordynamic behavior. The work in this dissertation presents: (1) the axisymmetric structural model of the rotors (2) the proposed dynamic pressure model, (3) the screw pump rotor response, (4) the experimental validation of the dynamic pressure model and rotor response. The topic of twin-screw pump rotordynamics is absent from the literature. The original contribution of the work presented in this dissertation to the field of rotordynamics includes: (1) demonstrating the adequacy of an axisymmetric model for modeling the screw section, (2) developing a model for predicting the dynamic pressure field around the screws, (3) characterization of the dynamic forces (synchronous and its harmonics) applied at the screw pump rotors, (4) predicting the dynamic response of twin-screw pump rotors due to hydrodynamic forces, (5) measuring the axial dynamic pressure in two circumferential planes around the screws to verify pressure predictions, (6) measuring the dynamic response of twin-screw pump rotor.
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Books on the topic "Positive displacement compressor"

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Sound and vibrations of positive displacement compressors. Boca Raton, Fla: CRC Press, 2007.

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Pandeya, Prakash N. Performance analysis of positive displacement refrigerating compressors. Ann Arbor: University MicrofilmsInternational, 1985.

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Soedel, Werner. Sound and Vibrations of Positive Displacement Compressors. CRC, 2006.

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Soedel, Werner. Sound and Vibrations of Positive Displacement Compressors. Taylor & Francis Group, 2010.

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Soedel, Werner. Sound and Vibrations of Positive Displacement Compressors. Taylor & Francis Group, 2006.

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Rotary Type Positive Displacement Compressors for General Refinery Service. 3rd ed. Amer Petroleum Inst, 1997.

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Application of Positive Displacement Compressors to Natural Gas Fuel Systems (Utilization Procedures S.). Institution of Gas Engineers and Managers, 1998.

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Rotary-Type Positive Displacement Compressors for General Refinery Services: Refining Department, May 1985 (Api Standard 619). Amer Petroleum Inst, 1985.

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Levy, David M., and Ieva Saule. General anaesthesia for caesarean delivery. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780198713333.003.0022.

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General anaesthesia (GA) is most often indicated for category 1 (immediate threat to life of mother or baby) caesarean delivery (CD) or when neuraxial anaesthesia has failed or is contraindicated. Secure intravenous access is essential. Jugular venous cannulation (with ultrasound guidance) is required if peripheral access is inadequate. A World Health Organization surgical safety checklist must be used. The shoulders and upper back should be ramped. Left lateral table tilt or other means of uterine displacement are essential to minimize aortocaval compression, and a head-up position is recommended to improve the efficiency of preoxygenation and reduce the likelihood of gastric contents reaching the oropharynx. Cricoid pressure is controversial. In the United Kingdom, thiopental remains the induction agent of choice, although there is scant evidence upon which to avoid propofol. In pre-eclampsia, it is essential to obtund the pressor response to laryngoscopy with remifentanil or alfentanil. Rocuronium is an acceptable alternative to succinylcholine for neuromuscular blockade. Sugammadex offers the possibility of swifter reversal of rocuronium than spontaneous recovery from succinylcholine. Management of difficult tracheal intubation is focused on ‘oxygenation without aspiration’ and prevention of airway trauma. The Classic™ laryngeal mask airway is the most commonly used rescue airway in the United Kingdom. There is a large set of data from fasted women of low body mass index who have undergone elective CD safely with a Proseal™ or Supreme™ laryngeal mask airway. Sevoflurane is the most popular volatile agent for maintenance of GA. The role of electroencephalography-based depth of anaesthesia monitors at CD remains to be established. Intraoperative end-tidal carbon dioxide tension should be maintained below 4.0 kPa.
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Book chapters on the topic "Positive displacement compressor"

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Neerken, Richard. "Positive Displacement Compressors, Pumps, and Motors." In Handbook of Fluid Dynamics and Fluid Machinery, 2187–217. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2008. http://dx.doi.org/10.1002/9780470172650.ch26.

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Ooi, Kim Tiow, and Kuan Thai Aw. "Design and Innovation in Rotary Positive Displacement Compressors." In Lecture Notes in Networks and Systems, 721–32. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-05230-9_86.

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"Multidimensional Compressor Sound." In Sound and Vibrations of Positive Displacement Compressors, 285–304. CRC Press, 2006. http://dx.doi.org/10.1201/9781420006445.ch11.

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"Chapter 4. Technical briefs on positive displacement compressors." In Compressor Technology Advances, 133–69. De Gruyter, 2021. http://dx.doi.org/10.1515/9783110678765-006.

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Meng, Yonggang, and Jintai Mi. "Numerical analyses of THD lubrication and dynamics of rolling piston and bearings in a rotary compressor." In Positive Displacement Machines, 225–61. Elsevier, 2019. http://dx.doi.org/10.1016/b978-0-12-816998-8.00009-1.

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"Compressor Housings that Are Not Axisymmetric." In Sound and Vibrations of Positive Displacement Compressors, 47–54. CRC Press, 2006. http://dx.doi.org/10.1201/9781420006445.ch4.

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"Forced Vibration of Compressor Housing (Shell)." In Sound and Vibrations of Positive Displacement Compressors, 60–79. CRC Press, 2006. http://dx.doi.org/10.1201/9781420006445.ch6.

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"Sound and Vibration of Compressor Valves." In Sound and Vibrations of Positive Displacement Compressors, 123–93. CRC Press, 2006. http://dx.doi.org/10.1201/9781420006445.ch9.

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"Natural Frequencies and Modes of Compressor Housings." In Sound and Vibrations of Positive Displacement Compressors, 19–46. CRC Press, 2006. http://dx.doi.org/10.1201/9781420006445.ch3.

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"Free and Forced Vibrations of Compressor Casings." In Sound and Vibrations of Positive Displacement Compressors, 81–94. CRC Press, 2006. http://dx.doi.org/10.1201/9781420006445.ch7.

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Conference papers on the topic "Positive displacement compressor"

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Paknezhad, Morad, Tooraj Yousefi, Sajjad Sadeghi, and Mehran Ahmadi. "Numerical and Experimental Investigation of Thermodynamic Behavior of Positive Displacement Compressor." In ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2010. http://dx.doi.org/10.1115/esda2010-24351.

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A numerical model, based on dynamic mesh, has been developed by FLUENT software, to simulate behavior of a positive displacement compressor. Only first compression stage of compressor was modeled. Modeling was done, by dividing the domain to three areas with different type meshes. Some relations were presented for volumetric, mechanical, isothermal, and overall isothermal performance, and thermodynamic analysis has been performed in term of these relations. Effects of outlet pressure and crankshaft’s angular velocity have been investigated on work, polytropic factor of compression, and efficiency. Numerical and experimental results have been compared, and a good agreement was seen between them.
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Roser, Holger. "Design and Analysis of Rotary Positive Displacement Mechanism for Oil-Less Compression." In ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2010. http://dx.doi.org/10.1115/esda2010-24665.

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In this paper, a simple positive displacement mechanism is investigated, which comprises two counter-rotating meshing rotors within a casing. Although considered for various applications more than a century ago, the basic geometry of this mechanism has not been further explored or adapted to modern gas compressor technology. As a fully balanced rotational mechanism operating at uniform angular velocity, potential applications range from pumps to expanders, from slow large displacement to high-speed devices; nonetheless, this research focuses on high-performance oil-less gas compressors as an ideal application. During one complete cycle, the main rotor compresses and discharges the fluid, whilst the secondary rotor seals the compression chamber. Important features of this mechanism are the circular profiles of the rotors, the potential to accommodate large ports for reduced flow losses, and ease of cooling. The simple geometry facilitates a cost-effective means of achieving tight operating clearances between rotors and casing for enhanced sealing without the need for liquid lubricants such as oil. This study and preliminary tests indicate that pressure ratios suitable for standard industrial applications can be obtained over a broad speed range, whilst minimizing friction and flow losses, a major drawback of current technologies. Moreover, two-phase compression and injection of liquids prior to compression have been studied and identified as a means to further improve efficiency and cooling.
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Vande Voorde, John B., and Jan Vierendeels. "ALE Calculations of Flow Through Rotary Positive Displacement Machines." In ASME 2005 Fluids Engineering Division Summer Meeting. ASMEDC, 2005. http://dx.doi.org/10.1115/fedsm2005-77353.

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In a rotating positive-displacement compressor, such as a screw compressor, only a time dependent flow calculation is meaningful. The Arbitrary Lagrangean-Eulerean (ALE) formulation of the flow equations allows CFD with moving grids. Due to the complex movement of the rotors, a powerful grid manipulator is necessary. The algorithm presented in this paper moves the nodes of a block-structured grid based on the solution of a Laplace potential-equation ∇2φ = 0 in a two-dimensional section of the flow domain. The qualities of a Laplace solution for grid generation have been used in grid generators and manipulators since Winslow. The difference with this new algorithm is that now this solution is explicitly obtained on an unstructured grid to allow greater control over the movement of the grid. The grid manipulation algorithm is demonstrated on an oil-free screw compressor geometry. Results of this calculation confirm the applicability of this algorithm to such complex geometries.
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Abdelwahab, Ahmed. "A Design Model of a New Positive Displacement Rotary Compressor Based on Trochoidal Geometry for High Pressure Applications." In ASME 2005 Power Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/pwr2005-50220.

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The desire to achieve high discharge pressures at low manufacturing and maintenance costs has resulted in the development of a number of new positive displacement rotary compressor designs. The proposed design involves a compressor with a trochoidal casing geometry and a rotor orbiting the casing interior. This arrangement generates a varying trapped volume between the rotor and the casing thus providing the necessary compression for the compressor. The major advantage of this design is its inherent simple two-dimensional configuration which makes it a very cheap device to manufacture. Furthermore, the oil-flooded lubrication system used with this design not only acts as a lubricant but also as a coolant to the main gas flow and consequently improves the mechanical reliability of the compressor. This paper presents a complete design model developed to investigate the performance of the compressor. The geometrical, kinematic, and dynamic equations of the casing and rotor are derived. A model of the compressor thermodynamic cycle and gasdynamic performance is presented. A comparison between the developed model and the experimental results of a prototype compressor testing is presented. The comparison shows that the developed model indeed captures the compressor performance trends with considerable accuracy at the design conditions. Deviation between the model and experimental results at the off design conditions is due to inaccuracies in the inlet and exit port loss models at the off design conditions.
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Heshmat, Hooshang, Andrew Hunsberger, Zhaohui Ren, Said Jahanmir, and James Walton. "On the Design of a Multi-Megawatt Oil-Free Centrifugal Compressor for Hydrogen Gas Transportation and Delivery: Operation Beyond Supercritical Speeds." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-40575.

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Deployment of a safe, efficient hydrogen production and delivery infrastructure on a scale that can compete economically with current fuels is needed in order to realize the hydrogen economy. While hydrogen compression technology is crucial to pipeline delivery, positive displacement (PD) compressors are costly, have poor reliability and use oil, which contaminates the hydrogen. To overcome poor reliability of the PD compressor, duplicate units are installed but at substantial costs. A totally oil-free, high-speed, efficient centrifugal compressor using 4th generation compliant foil bearings and seals has been designed for hydrogen pipeline delivery. Using 6-12 megawatt drives operating at speeds to 56,000 rpm, a modular, double entry compressor was configured to deliver 500,000 kg/day at pressures greater than 8 MPa. Each of the two or three multi-stage compressor frames operate above its bending critical speed since speeds are 5 to 7 times faster than conventional compressors. To assure a structurally and economically feasible design, the rotor of each compressor spins at the same speed with blade tip velocities below 600 m/s. An iterative aerodynamic/structural/rotordynamic design process was used, including both quasi-three dimensional inviscid internal flow and Computational Fluid Dynamic (CFD) analyses. The flow field was carefully analyzed for areas of excessive diffusion, sudden velocity gradients and flow separation. Excellent correlation between the preliminary design and CFD analyses was obtained. Structural and rotor-bearing system dynamic analyses were also completed to finalize the compressor system configuration. Finite element analysis of the compressor impeller was used to verify structural integrity and fatigue limits for selected materials. Rotor-bearing system analysis was used to define acceptable bearing locations and dynamic coefficients, system critical speeds and dynamic stability. Given the high speeds, supercritical operation, and required reliability, efficiency and freedom from contaminants, compliant foil gas bearings were selected and designed. Since hydrogen will be used as the bearing lubricant for the foil bearings, substantially lower power loss than oil lubricated bearings will be experienced and the auxiliary supply or scavenge system is eliminated.
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Mahmoud, A. M., S. A. Sherif, and W. E. Lear. "Development and Testing of a Rotary-Vane Two-Phase Refrigerating Expander." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-13234.

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Rotary-vane positive displacement machines have played an important role for many years in refrigeration and air compression applications because of their inherent simplicity and reliability. This paper details the development and testing of a rotary-vane two-phase expander for the purpose of work recovery in an air-cooled chiller. The paper describes the methodology used to design an expander for two-phase flow from a single-phase compressor and an air-motor. Input from detailed analytical models developed by the authors are used to improve the expander design with respect to internal leakage losses and friction. Controls and performance testing are also presented. Directions for future research are highlighted.
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Pascu, Maria, Manoj Heiyanthuduwage, Sebastien Mounoury, Graeme Cook, and Ahmed Kovacevic. "A Study on the Influence of the Suction Arrangement on the Performance of Twin Screw Compressors." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-62391.

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Screw compressors are complex flow systems, but operate upon simple considerations: they are positive displacement machines consisting of meshing rotors contained in a casing to form a working chamber, whose volume depends only on the angle of rotation. Their performance is highly affected by leakages, which is dependent on various clearances and the pressure differences across these clearances. Nowadays, the manufacturing and profiling techniques have matured so much, that rotors of even the most complex shapes can be manufactured to tolerances in the order of few microns, resulting in high efficiencies. With manufacturing tolerances this tight, there is only small amount of improvement expected from further exploration of this venue, and a rather different direction for analysis may be more rewarding, i.e. other components of the screw compressor, like the suction and discharge areas. While the available literature includes several references on improvements of the compressor performance based on the analysis of the discharge port and discharge chamber, the investigation of the suction arrangement and inlet port remains fairly unexplored. This is the area of concern for the present paper, where the influence of the port shape and suction arrangement on the overall compressor performance is investigated. Two suction models were investigated for a standard screw compressor by means of CFD, which allowed in-depth analyses and flow visualizations, confirmed by the experimental investigation carried out on the actual compressor.
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Sengupta, Amrita, Prashant Kumar, Pardeep Garg, Nirmal Hui, Matthew S. Orosz, and Pramod Kumar. "Moment Analysis of a Scroll Expander Used in an Organic Rankine Cycle." In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-26935.

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Recent studies on small-scale power generation with the organic Rankine cycle suggest superior performance of positive displacement type of expanders compared to turbines. Scroll expanders in particular achieve high isentropic efficiencies due to lower leakage and frictional losses. Performance of scroll machines may be enhanced by the use of non-circular involute curves in place of the circular involutes resulting non-uniform wall thickness. In this paper, a detailed moment analysis is performed for such an expander having volumetric expansion ratio of 5 using thermodynamic models proposed earlier by one of the present authors. The working fluid considered in the power cycle is R-245fa with scroll inlet temperature of 125 °C for a gross power output of ∼3.5 kW. The model developed in this paper is verified with an air scroll compressor available in the literature and then applied to an expander. Prediction of small variation of moment with scroll motion recommends use of scroll expander without a flywheel over other positive displacement type of expanders, e.g. reciprocating, where a flywheel is an essential component.
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Mahkamov, Khamid, Irina Makhkamova, and Fadi Kahwash. "Novel Twin-Screw Stirling Cycle Machine for Cryogenic and Refrigeration Applications." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-86853.

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This paper describes design and principles of operation of a novel rotary type Stirling cycle machines based on rotary positive displacement mechanisms such as twin-screw, gate rotor screw, scroll, and conical screw compressors and expanders. When these mechanisms are used as separate expanding or compressing machines, the flow of the gas is one-directional with volumes of chambers varying in accordance with a saw-tooth type function. The proposed design solution combines at least two units of gas-coupled compressor and expander arrangements with a required shift in the shaft angle. Every unit has a series of gas channels for timing the connection of its compressor and expander parts. Units are connected to each other via a set of heat exchangers, which are conventional for Stirling cycle machines: recuperative cooling and warm heat exchangers with a regenerator, built between them. The operational capability is demonstrated using three-dimensional CFD simulations. Computational results demonstrate reciprocating flow of the gas between units, as in conventional Stirling machines, and functioning of the proposed design as a multi-cylinder, double acting Stirling machine. The suggested design makes it possible to achieve full dynamic balancing, especially in the case of twin-screw and gate rotor mechanisms, due to the rotation of screws around their axes. It also eliminates a number of problems, which are specific to Stirling machines with reciprocating pistons and their kinematic drive mechanisms.
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Vance, John M., Bradley P. Cardon, Luis A. San Andres, and Albert F. Storace. "A Gas Operated Bearing Damper for Turbomachinery." In ASME 1991 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1991. http://dx.doi.org/10.1115/91-gt-249.

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A gas operated bearing damper for turbomachinery has been designed, analyzed, and experimentally investigated in the laboratory. The damper utilizes air bled off from the compressor to power an actuator through orifices with area modulated by the vibratory displacement at the bearing support. The design objective for this passive device is to make the actuating dynamic gas pressure phase lead the vibratory displacement by 90 degrees. Several variations of the basic concept have been tested. An analysis was performed to guide the experiments. All of the designs tested to date can produce positive damping, and one particular design has produced a damping coefficient of 8756 N-s/m (50 lb-sec/in) with a power penalty of 5.2 KW (7 HP) at 310 KPa (45 psi). This design was installed on a laboratory rotor with flexibly supported ball bearings, and significant damping of the critical speed response was demonstrated. The experimental results to date suggest that further research can produce significant improvements in performance, and the device appears to be especially adaptable to high temperature applications for aircraft engines.
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Reports on the topic "Positive displacement compressor"

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Starodetko, Konstantin E., Simon Simand, Tcheslav B. Drobychevskj, Vladimir J. Belyaev, Konstantin N. Yurchuk, Aliaksandr A. Vitsiaz, and Dmitriy V. Kuzmenkov. High Performance Characteristics of a Motorcycle Powered by a Four-Stroke Small 50cc-125cc Engine at the Expense of a Positive Displacement Air Compressor as a Supercharger. Warrendale, PA: SAE International, October 2013. http://dx.doi.org/10.4271/2013-32-9015.

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Yashar, David A., and W. Vance Payne. Vibration signatures for three positive displacement compressors. Gaithersburg, MD: National Institute of Standards and Technology, 2004. http://dx.doi.org/10.6028/nist.ir.7183.

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