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Academic literature on the topic 'Flow-through method (Accounting)'
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Journal articles on the topic "Flow-through method (Accounting)"
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Dunham, J. "Modelling of spanwise mixing in compressor through-flow computations." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 211, no. 3 (May 1, 1997): 243–51. http://dx.doi.org/10.1243/0957650971537150.
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Although three-dimensional Navier-Stokes computations are coming into use more and more, streamline curvature through-flow computations are still needed, especially for multistage compressors, and where codes which run in minutes rather than hours are preferred. These methods have been made more realistic by taking account of end-wall effects and spanwise mixing by four aerodynamic mechanisms: turbulent diffusion, turbulent convection by secondary flow, spanwise migration of aerofoil boundary layer fluid and spanwise convection of fluid in blade wakes. This paper describes the models adopted in the DRA streamline curvature method for axial compressor design and analysis. Previous papers are summarized briefly before describing the new part of the model—that accounting for aerofoil boundary layers and wakes. Other changes to the previously published annulus wall boundary layer model have been made to enable it to cater for separations and end bends. The resulting code is evaluated against a range of experimental and computational results.
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Bontempo, R., and M. Manna. "A nonlinear and semi-analytical actuator disk method accounting for general hub shapes. Part 1. Open rotor." Journal of Fluid Mechanics 792 (March 8, 2016): 910–35. http://dx.doi.org/10.1017/jfm.2016.98.
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The paper presents a newly developed method for the analysis of the flow around open rotors characterised by hubs of general shape. The exact and implicit solution of the axysimmetric, inviscid and incompressible flow is represented as the superposition of infinite ring vortices properly arranged along the hub surface and the rotor wake. The solution is made explicit through a semi-analytical and iterative procedure. The proposed semi-analytical approach can deal with hubs of arbitrary shape and with quite general rotor load distributions. The method strongly couples the flow induced by the rotor and the hub. Moreover, the contraction/divergence and the rotation of the wake can be fully taken into account. The results of the semi-analytical method are also compared with those obtained with a widely diffused actuator disk model based on computational fluid dynamics (CFD) techniques. Finally, in comparison with more advanced methods, such as those relying on a CFD approach, this method is characterised by an extremely reduced computational cost. The computer code is freely available on contacting the authors.
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Praquin, Nicolas. "THE CRÉDIT LYONNAIS IN FRANCE (c. 1871–1918): USING CASH FLOW ANALYSIS TO ASSESS RISK IN BANKING." Accounting Historians Journal 37, no. 1 (June 1, 2010): 1–28. http://dx.doi.org/10.2308/0148-4184.37.1.1.
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In the absence of accounting rules, financial reports and disclosures were of little use to shareholders and stakeholders before World War I. To offset the unreliability of financial information, several banks, including the Crédit Lyonnais, implemented a system of accounting analysis that, in essence, anticipated modern financial-analysis tools based on funds statements and cash-flow statements. This paper, based on the Crédit Lyonnais archives, sets out to explain the purpose of this method, to present the different concepts employed, and to show how they interact. The relevance of this model is assessed through two case studies.
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Stevcevska Srbinoska, Dusica, Angela Ljamova, and Snezhana Hristova. "Factors Affecting the Adoption of Inventory Cost Flow Method by the Macedonian Companies: FIFO, Weighted Average, and Specific Identification Method." Studia Universitatis Babeș-Bolyai Negotia 65, no. 3 (September 30, 2020): 31–76. http://dx.doi.org/10.24193/subbnegotia.2020.3.02.
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"Inventory valuation is a major topic in the accounting practice. Inventory valuation is reflected in financial reporting, i.e. the balance sheet and the profit and loss account and the choice of the right inventory cost flow method is one of the basic decisions all companies engaged in manufacturing and distribution of goods need to make. Preferably, the chosen method should result in the best income and financial result measurement. However, no method is acknowledged to always be the best for accomplishing these objectives. The main aim of this paper is to investigate the factors affecting the adoption of inventory cost flow method by Macedonian companies. The data was collected by using a questionnaire randomly distributed via email to Macedonian retailing and manufacturing companies and later examined through statistical methods. Analyzing a pool of 56 respondents, we find that the subject of inventory valuation is important as most of the participants consider that they understand the existing inventory valuation methods. The choice of inventory valuation method is mostly affected by the level of education of the manager, understanding of the method and simplicity of the separate inventory valuation methods. Key words: Inventory, valuation, methods, FIFO, weighted average, specific identification; JEL classification: M4, M1 "
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Aleinikovas, Marius, Gediminas Jasinevičius, Mindaugas Škėma, Lina Beniušienė, Benas Šilinskas, and Iveta Varnagirytė-Kabašinskienė. "Assessing the Effects of Accounting Methods for Carbon Storage in Harvested Wood Products on the National Carbon Budget of Lithuania." Forests 9, no. 12 (November 26, 2018): 737. http://dx.doi.org/10.3390/f9120737.
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Forests and the forest-based sector play important roles in mitigating climate change through carbon sequestration and storage in living biomass and soil. In Europe, the forest sector is the only sector that positively affects atmospheric carbon balance. After the forest harvest, a large share of carbon is removed together with the wood. This wood carbon might be stored for centuries if in the form of long-lived wood products. In 2011, the United Nations decided that countries should account for and report carbon balance not only in forests but also in harvested wood products (HWP), followed by very general guidelines on methods for carbon accounting in HWP. The Intergovernmental Panel on Climate Change (IPCC) proposed three methodological levels called tiers for estimating carbon stock and its changes in HWP. The first reporting period revealed that countries applied different carbon accounting methods (tiers), therefore comparing the carbon budgets of HWP and the effect of climate change mitigation among different countries is difficult. In order to test the differences between carbon accounting methods proposed by the IPCC guidelines, we applied two carbon accounting methods and used different data sources in the case of Lithuania. The methods applied were the IPCC Tier 2 method (data on HWP from statistics or the literature, default half-life values, and default HWP categories) and material flow analysis, which is compatible with the IPCC Tier 3 method (material flow data on HWP, country-specific half-life values, and country-specific HWP categories). Depending on the availability of historical data from different sources for the purpose of this study, three study periods were defined: 1992–2015 Food and Agriculture Organization Corporate Statistical Database (FAOSTAT) data, 1960–1991 data from the literature, and 1940–1991 data from national statistics. The study findings show that carbon stock in HWP significantly differed when different data sources and methods were applied. The highest carbon stock in HWP (19.5 Mt) at the end of the study period was observed when FAOSTAT data from 1992–2015 were used and the Tier 3 method was applied. The lowest carbon stock in HWP (11.2 Mt) at the end of the study period was observed when data from national statistics from 1940–1991 were used and the Tier 2 method was applied. The carbon inflow into the pool of HWP in all cases was estimated to be 40% higher when material flow analysis was applied compared to the IPCC default (Tier 2) method. These findings suggest that in general it is more reasonable to apply the Tier 3 method for carbon accounting of HWP in Lithuania.
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Turner, Jerry L. "A Top-Down Approach to Identification and Documentation of Critical Accounting Application Controls." Current Issues in Auditing 1, no. 1 (January 1, 2007): A12—A20. http://dx.doi.org/10.2308/ciia.2007.1.1.a12.
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SUMMARY: PCAOB Auditing Standard No. 5 prescribes assessing internal controls over financial reporting using a “top-down” approach. This paper describes a method for documenting internal controls that aligns the documentation for application controls to the overall top-down audit approach. This method identifies critical data flow paths by beginning with the general ledger and tracing data backward (down) through the system to its origin, effectively focusing on the critical data repositories in the financial reporting process. It also directs attention to the processes that affect critical financial data and to where controls related to those processes should exist based on management assertions about financial statement account balances. The approach is both more efficient and effective than traditional bottom-up documentation approaches.
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Peters, Matt D. "The Frozen Supply Chain Business Case: A Management Accounting Instructional Resource." Issues in Accounting Education 36, no. 3 (April 26, 2021): 135–60. http://dx.doi.org/10.2308/issues-2019-512.
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ABSTRACT This case guides students through the process of preparing a real-life business case. The business case involves capital expenditure analysis for a potential project in the Wally-Mart Supermarkets frozen supply chain. There are three parts to the business case: (1) prepare a financial model in Excel with a discounted cash flow method to analyze relevant incremental capital expenditures, revenues, costs, and profits; (2) concisely communicate the financial model and business case in a business style Word report; and (3) concisely communicate the financial model and business case in a business style PowerPoint presentation. The case materials include a practice financial modeling exercise. The case is suitable for use in undergraduate and graduate management accounting courses.
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Neicu, Marian Ştefan, and George Gustav Savii. "Validating Algorithms and Methods Destined for Information System Design Meant for the Business Environment Using Simulated Companies." Applied Mechanics and Materials 657 (October 2014): 931–35. http://dx.doi.org/10.4028/www.scientific.net/amm.657.931.
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The paper presents a validation method of the information systems conceived for the business environment. Unlike the audit of the accounting information systems or of the established testing methods of the software, we suggest that for testing and validation of the information systems, they should be implemented and used through enterprise exercise. Through this, besides the actual check of the software we also evaluate the way in which the software applications adapt to the full running of a processing flow of the information, corresponding to some basic functions of the enterprise. In such way we obtain complete and good quality results, at low costs of the evaluation process.
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Rue, Joseph C., and Ara G. Volkan. "The Income Tax Accounting Controversy: A Matter Of Perspective." Journal of Applied Business Research (JABR) 13, no. 4 (September 7, 2011): 107. http://dx.doi.org/10.19030/jabr.v13i4.5745.
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<span>The study examines SFAS No. 96 and SFAS No. 109 in the context of the unit problem. The unit problem involves the selection of the appropriate perspective for applying measurement and recognition conventions to the phenomenon of interest. From an individual event perspective, the FASBs conclusions regarding liability recognition are inconsistent with their definition of a liability found in State of Finance Accounting Concepts No. 6. In addition, the use of inconsistent perspectives by the SFAS No. 96 and SFAS No. 109 create disagreements with the Boards positions. The simultaneous use of both the individual and aggregate perspectives as the basis of the Boards decisions is the source of these disagreements. The study argues that the income tax accounting issue should be viewed from an aggregate perspective and concludes that the flow through method of accounting for income taxes should be adopted.</span>
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Colley, Ron, Joseph Rue, Adrian Valencia, and Ara Volkan. "Accounting For Deferred Taxes: Time For A Change." Journal of Business & Economics Research (JBER) 10, no. 3 (March 20, 2012): 149. http://dx.doi.org/10.19030/jber.v10i3.6873.
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<p>This study examines the theory underlying the current accounting and reporting standards for deferred taxes. Given the goal of global accounting convergence and under the proposed condorsement approach, the FASB and the IASB have a historic opportunity to revise the existing deferred tax accounting standards. Thus, it is warranted to illustrate the financial consequences of using the proposed flow-through (where tax expense is equal to the statutory tax liability) approach versus the asset-liability method of accounting for deferred taxes. We achieve this objective by computing the change in the debt-to-equity (DTE) ratios for the 2004-2010 period when net deferred tax balances are eliminated and corresponding adjustments are made in the total liability and stockholders equity balances. Based on our observations, we propose that the underlying issue in accounting for deferred taxes is the unit problem and argue that deferred taxes do not represent assets and liabilities as defined by accounting standards.<strong></strong></p>
Books on the topic "Flow-through method (Accounting)"
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Canada. Dept. of Finance. Flow-through shares: An evaluation report. Ottawa, Ont: Dept. of Finance, 1994.
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Library of Congress. Congressional Research Service, ed. American Telephone and Telegraph Co. flow-through of state gross receipts taxes. Washington, D.C: Library of Congress, Congressional Research Service, 1987.
Find full textConference papers on the topic "Flow-through method (Accounting)"
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Akhatov, Iskander S., Justin M. Hoey, Drew Thompson, Artur Lutfurakhmanov, Zakaria Mahmud, Orven F. Swenson, Douglas L. Schulz, and Alexander N. Osiptsov. "Aerosol Flow Through a Micro-Capillary." In ASME 2009 Second International Conference on Micro/Nanoscale Heat and Mass Transfer. ASMEDC, 2009. http://dx.doi.org/10.1115/mnhmt2009-18421.
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A combined theoretical/experimental study of micron size aerosol flows through micro-capillaries of diameter about 100 μm and length about 1 cm is presented. It is shown that under proper conditions at a relatively high velocity of about 100 m/s such an aerosol flow reveals a new manifestation of microfluidics: the Saffman force acting on aerosol particles in gas flowing through a micro-capillary becomes significant thereby causing noticeable migration of particles toward the center line of the capillary. This finding opens up new opportunities for aerosol focusing, which is in stark contrast to the classical aerodynamic focusing methodologies where only particle inertia and the Stokes force of gas-particle interaction are typically used to control particle trajectories. A mathematical model for aerosol flow through a micro-capillary accounting for complicated interactions between particles and carrier gas is presented. This model describes the experimental observables obtained via shadowgraphy for aerosol beams exiting micro-capillaries. It is further shown that it is possible to design a micro-capillary system capable of generating a Collimated Aerosol Beam (CAB) in which aerosol particles stay very close to a capillary center line. The performance of such a CAB system for direct-write fabrication on a substrate is demonstrated. The lines deposited by CAB for direct-write fabrication are shown to exhibit widths of less than 5 μm — superior to ink-jet. Materials deposition based upon directed aerosol flow has the potential of finding application in the fields of flexible electronics, sensors, and solar cells. In this paper, the genesis of a new materials deposition method termed Collimated Aerosol Beam Direct-Write (CAB-DW) is discussed.
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Kashaninejad, Navid, Weng Kong Chan, and Nam-Trung Nguyen. "Fluid Mechanics of Flow Through Rectangular Hydrophobic Microchannels." In ASME 2011 9th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2011. http://dx.doi.org/10.1115/icnmm2011-58140.
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In this study, the effect of two important parameters have been evaluated for pressure driven liquid flows in microchannel in laminar regime by analytical modeling, followed by experimental measurement. These parameters are wettability conditions of microchannel surfaces and aspect ratio of rectangular microchannels. For small values of aspect ratio, the channel was considered to have a rectangular cross-section, instead of being two parallel plates. Novel expressions for these kinds of channels were derived using eigenfunction expansion method. The obtained two-dimensional solutions based on dual finite series were then extended to the case of a constant slip velocity at the bottom wall. In addition, for large values of aspect ratio, a general equation was obtained which is capable of accounting for different values of slip lengths for both upper and lower channel walls. Firstly, it was found out that for low aspect ratio microchannels, the results obtained by analytical rectangular 2-D model agree well with the experimental measurements as compared to one dimensional solution. For high aspect ratio microchannels, both models predict the same trend. This finding indicates that using the conventional 1-D solution may not be accurate for the channels where the width is of the same order as the height. Secondly, experimental results showed that up to 2.5% and 16% drag reduction can be achieved for 1000 and 250 micron channel height, respectively. It can be concluded that increasing the surface wettability can reduce the pressure drop in laminar regime and the effect is more pronounced by decreasing the channel height.
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Campbell, Bryce K., Kelli Hendrickson, Yuming Liu, and Randy Roberts. "Nonlinear Effects on Interfacial Wave Growth Into Slug Flow." In ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-79397.
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The objective of this study is to understand the effects of non-linearity on the interfacial stability of a two fluid stratified flow through a horizontal channel. An efficient perturbation expansion based high-order spectral method is developed, for the simulation of the generation and nonlinear evolution of interfacial waves. The method is capable of accounting for the nonlinear interactions of a large number of wave components in a broadband spectrum, and obtains an exponential convergence of the solution with grid refinement and interaction order. The method is applied to investigate the role that nonlinear effects have on the initial development of Kelvin-Helmholtz (KH) instabilities and nonlinear wave-wave interactions with the purpose of gaining insight into the physical mechanisms which cause slug flow. It will also be demonstrated that nonlinearity can introduce unstable inter-facial wave growth in regions predicted to be stable by linear analysis. In addition, it is shown that energy transfer from short (KH unstable) waves to long (KH stable) waves due to nonlinear resonant wave-wave interactions is an effective mechanism for the development of slug flow.
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Taghva, Maral, and Lars Damkilde. "Analysis of Transient Two-Phase Flow in Pressure Safety Valve Outlet Headers." In ASME 2018 5th Joint US-European Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/fedsm2018-83142.
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To protect a pressurized system from overpressure, one of the most established strategies is to install a Pressure Safety Valve (PSV). Therefore, the excess pressure of the system is relieved through a vent pipe when PSV opens. The vent pipe is also called “PSV Outlet Header”. After the process starts, a transient two-phase flow is formed inside the outlet header consisting of high speed pressurized gas interacting with existing static air. The high-speed jet compresses the static air towards the end tail of the pipe until it is discharged to the ambiance and eventually, the steady state is achieved. Here, this transient process is investigated both analytically and numerically using the method of characteristics. Riemann’s solvers and Godunov’s method are utilized to establish the solution. Propagation of shock waves and flow property alterations are clearly demonstrated throughout the simulations. The results show strong shock waves as well as high transient pressure take place inside the outlet header. This is particularly important since it indicates the significance of accounting for shock waves and transient pressure, in contrast to commonly accepted steady state calculations. More precisely, shock waves and transient pressure could lead to failure, if the pipe thickness is chosen only based on conventional steady state calculations.
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Lyras, Konstantinos, Siaka Dembele, C. Madhav Rao Vendra, and Jennifer Wen. "Numerical simulation of superheated jets using an Eulerian method." In ILASS2017 - 28th European Conference on Liquid Atomization and Spray Systems. Valencia: Universitat Politècnica València, 2017. http://dx.doi.org/10.4995/ilass2017.2017.4667.
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Flash boiling is the rapid phase change of a pressurised fluid that emerges in ambient conditions below its vapourpressure. Flashing can occur either inside or outside the nozzle depending on the local pressure and geometry and the bubble formation leads to interfacial interactions that eventually influence the emerging spray. Lagrangian methods which exist in literature to simulate the flash atomisation and inter-phase heat transfer employ many sim- plifying assumptions. Typically, sub-models used for the break-up, collisions and evaporation introduce an extensive empiricism that might result in unrealistic predictions for cases like flashing. In this study, a fully Eulerian approach is selected employing the Σ − Y model proposed by Vallet and Borghi. The model tracks liquid structures of any shape and computes the spray characteristics comprising a modified version for the transport equation of the sur- face density. The main goal of this study is to investigate the performance of this model in flash boiling liquids using the Homogeneous Relaxation Model (HRM) developed by Downar-Zapolski, a model capable of capturing the heat transfer under sudden depressurisation conditions accounting for the non-equilibrium vapour generation. The model in this present study considers that the instantaneous quality would relax to the equilibrium value over a given timescale which is calculated using the flow field values. A segregated approach linking the HRM and Σ − Y is implemented in a compressible formulation in an attempt to quantify the effects of flash boiling in the spray dynamics. The developed model is naturally implemented in RANS in a dedicated solver HRMSonicELSAFoam. Results from simulations of two-phase jets of different subcooled fluids through sharp-edged orifices show that the proposed approach can accurately simulate the primary atomisation and give reliable predictions for the droplet sizes and distribution. Strong effects of the flashing and turbulent mixing on the jet are demonstrated. The model istested for turbulent flows within small nozzles and was developed within the open source code OpenFOAM.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4667
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Wunsch, Dirk, Charles Hirsch, Rémy Nigro, and Gregory Coussement. "Quantification of Combined Operational and Geometrical Uncertainties in Turbo-Machinery Design." In ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-43399.
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The NASA rotor 37 is investigated accounting for as many as 9 simultaneous operational and geometrical uncertainties. The combined influence of uncertainties on input quantities such as the total inlet pressure, static outlet pressure, tip gap or leading and trailing edge angles on output quantities is studied. These simulations provide results which go far beyond the standard deterministic simulation. A probabilistic collocation method in combination with a sparse grid quadrature is introduced into the software suite FINE™ propagating combined operational and geometrical uncertainties in complex 3D CFD simulations. The modification of the parameterized geometry and the consequent re-meshing is provided by a fully automatic tool, which also couples with the flow solver and provides post-treatment routines. It is this automation, which makes this kind of study feasible. A manual modification of geometry, manual meshing and simulation set-up accounting for a multitude of simultaneous uncertainties is simply unfeasible for as many as hundreds of complex 3D turbo-machinery simulations. This work represents thus a break-through in the uncertainty management towards the application of uncertainty propagation in the daily engineering practice.
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Zhang, Xiawen, Yaping Ju, and Chuhua Zhang. "Accuracy and Sensitivity Analysis of Aerodynamic Performance Prediction Models for Transonic Axial-Flow Compressors." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-15172.
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Abstract The mean-line method, as the corner stone of preliminary aerodynamic design of axial-flow compressors, is heavily dependent on the accuracy and robustness of empirical prediction models, mainly the deviation models and loss models. A large number of such models have been developed, however, a comprehensive evaluation of their prediction capabilities was lacked yet. To carry out the accuracy and sensitivity analysis of these prediction models developed in the both academic and industry communities, we here developed a one-dimensional mean-line method which implements several widely used deviation and loss models. Then, the developed mean-line method was applied to predict the speed-lines of aerodynamic performance for three representative transonic axial-flow compressors, i.e., NASA Rotor 35, NASA Stage 35 and NASA 74A first front three-stage. The parallel coordinates method was particularly adopted to effectively perform the sensitivity analysis of totally 2448 combinations of deviation and loss models through a heuristic comparison of the model predictions with the available experimental data. The accuracy analysis indicates that, by using the best model combinations, the prediction error of peak efficiency point is generally kept below 2% whereas that of surge margin varies significantly from 3.03% to 18.93%. However, the most accurate model combination is dependent on the compressor type and rotational speed. The sensitivity analysis shows that the prediction robustness is remarkably influenced by the deviation model accounting for axial velocity ratio effect, the design shock loss model and the off-design total loss model. This work provides the design engineers with prediction model selection, and the model developers with prediction improvement direction for axial-flow compressors.
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Sharma, A., S. K. S. Boetcher, W. A. Aissa, and M. J. Traum. "Impact of Interstitial Mass Transport Resistance on Water Vapor Diffusion Through Southern Mills Defender™ 750 Fabric Layers." In ASME/JSME 2011 8th Thermal Engineering Joint Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajtec2011-44485.
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Textiles maintain wearer comfort by allowing evaporated sweat to permeate through, providing thermal management and keeping skin dry. Each textile layer presents a resistance to mass transport consistent with its physical structure (i.e., thickness, porosity, and tortuosity). However, when textiles are layered, water vapor transport becomes more complex because diffusing molecules must traverse interstitial spaces between layers. Interstitial mass transport resistances of significant magnitude can reduce rates of water vapor transport through layered textile stacks. The prevailing textile mass transport resistance interrogation method is ASTM F1868: “Standard Test Method for Thermal and Evaporative Resistance of Clothing Materials Using a Sweating Hot Plate.” A self-calibrating element of this method is to measure one, two, three, and four fabric layers. Each newly added layer is prescribed to increase the stack mass transport resistance by the integer resistance presented by a single layer with no interstitial resistance consideration. Four improvements to ASTM F1868 are recommended: 1) gravimetric mass transport measurement, 2) a Stefan flow model, 3) correct accounting for apparatus mass transport resistances, and 4) recognizing and measuring interstitial mass transport resistances. These improvements were implemented and evaluated by running tests using Southern Mills Defender™ 750 fabric, the calibration standard used for ASTM F1868, on a new gravimetric experimental apparatus. The mass transport resistance of one fabric layer measured via the gravimetric method is related to the ASTM F1868 value through working fluid properties. Using the gravimetric approach, mass transport resistance for a single layer of calibration fabric was measured at 60.3 ± 14.4 s/m, which is consistent with the prescribed result from ASTM F1868 (after the conversion factor), 73.1 ± 7.3 s/m. The diffusion coefficient for water vapor in air in the fabric pores measured by gravimetric experiment, (2.02 ± 0.59) × 10−5 m2/s, agrees (within experimental uncertainty) with the theoretical value for the experimental conditions, 2.54 × 10−5 m2/s. However, for stacks of two or more calibration fabric layers, the gravimetric approach does not agree with the prescribed ASTM F1868 result due to interstitial mass transport resistance between fabric layers. The measured interstitial resistance value is 23.6 s/m, 39.1% of a single fabric layer, a value too significant to be ignored in engineering analysis.
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Nicoud, D., J. Brochet, and M. Goutines. "A Methodology Proposal to Design and Analyse Counterrotating High Speed Propellers." In ASME 1989 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1989. http://dx.doi.org/10.1115/89-gt-38.
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Contrarotating high speed propellers are able to significantly reduce fuel consumption of high subsonic aircrafts. The achievement of this goal requires the optimization of the transonic flowfield on the blades in order to obtain high efficiency. For several years, 2D and 3D aerodynamic computational methods have been used to design high performance turbofans. A similar methodology can be developed for high speed propeller design, and this paper presents a typical application of such methods. We first present an application of the through-flow method. An outer fictitious casing is chosen in order to simulate undisturbed flow far from the propellers, and the mesh is adapted to the high swept blades. Radial distribution of loading is selected using aerodynamic criteria. Then, a quasi geometrical method supplies the bidimensional profiles accounting for structural specifications such as chord length, maximum thickness and root attachment. Suction side incidence and downstream deviation are also specified. After the profile stacking operations, which use conformal application on the axisymetric stream surfaces, the tridimensional transonic flowfield is drawn by a 3D Euler solver on an appropriate domain. This code uses a multi-domains technique and includes the energy equation for non-constant rothalpy cases. Particular interest is focused on the Mach number distributions and on the shock strength. The final loss prediction is made by means of a shock loss model and a bidimensional boundary layer calculation based on the Euler static pressure distributions. The profile shapes are modified and the above process is repeated until the required deflection, a convenient throat margin, and sufficiently thin and well attached boundary layers are obtained. Finally, the global performances are issued from 3D Euler and boundary layer computations, completed by the calculation of secondary flow effects.
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Hassan, Salah, and Sohel Anwar. "Soot Mass Estimation From Electrical Capacitance Tomography Imaging for a Diesel Particulate Filter." In ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-11295.
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Abstract The Electrical capacitance tomography (ECT) method has recently been adapted to obtain tomographic images of the cross section of a diesel particulate filter (DPF). However, a soot mass estimation algorithm is still needed to translate the ECT image pixel data to obtain soot load in the DPF. In this paper, we propose an estimation method to quantify the soot load in a DPF through an inverse algorithm that uses the ECT images commonly generated by a back-projection algorithm. The grayscale pixel data generated from ECT is used in a matrix equation to estimate the permittivity distribution of the cross section of the DPF. Since these permittivity data has direct correlation with the soot mass present inside the DPF, a permittivity to soot mass distribution relationship is established first. A numerical estimation algorithm is then developed to compute the soot mass accounting for the mass distribution across the cross-section of the DPF as well as the dimension of the DPF along the exhaust flow direction. Experimental data has been used to validate the proposed soot estimation algorithm which compared the estimated values with the actual measured soot mass. The estimated soot mass for various soot load amounts were found to correlate reasonably well with the measured soot masses in those cases.