A One-Dimensional Model for Heat Transfer in Engine Exhaust Systems

We develop a simple model in which longitudinal, compressible, unsteady heat transfer between heater and gas is computed in the small-Mach-number limit. This calculation is used to determine the transfer function of the heater, which plays an important role in the stability limits of the thermoacoustic instability of the Rijke tube. The transfer function is determined analytically in the limit of small expansion parameter γ, and numerically for γ of order unity. In the case ρμ/cp = constant, an analytical solution can be found.

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Pool boiling heat transfer and simplified one-dimensional model for prediction on coated porous surfaces with vapor channels

International Journal of Heat and Mass Transfer ◽

10.1016/s0017-9310(01)00192-2 ◽

2002 ◽

Vol 45 (5) ◽

pp. 1117-1125 ◽

Cited By ~ 30

Author(s):

Wei Wu ◽

Jian-Hua Du ◽

Xue-Jiao Hu ◽

Bu-Xuan Wang

Keyword(s):

Heat Transfer ◽

Boiling Heat Transfer ◽

Pool Boiling ◽

Dimensional Model ◽

One Dimensional ◽

Pool Boiling Heat Transfer ◽

Porous Surfaces

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One Dimensional Model for Rotating Channels in the Turbine System: Part 2 — Formulation and Validation for Film Condensation

Volume 1: Fuels and Combustion, Material Handling, Emissions; Steam Generators; Heat Exchangers and Cooling Systems; Turbines, Generators and Auxiliaries; Plant Operations and Maintenance ◽

10.1115/power2013-98127 ◽

2013 ◽

Author(s):

Murali Krishnan R. ◽

Zain Dweik ◽

Deoras Prabhudharwadkar

Keyword(s):

Heat Transfer ◽

Heat Transfer Coefficient ◽

Transfer Coefficient ◽

Steam Turbine ◽

Compressible Flow ◽

Saturation Temperature ◽

Film Condensation ◽

Bulk Temperature ◽

Dimensional Model ◽

One Dimensional

This paper provides an extension of the previously described [1] formulation of a one-dimensional model for steady, compressible flow inside a channel, to the steam turbine application. The major challenge faced in the network simulation of the steam turbine secondary system is the prediction of the condensation that occurs during the engine start-up on the cold parts that are below the saturation temperature. Neglecting condensation effects may result in large errors in the engine temperatures since they are calculated based on the boundary conditions (heat transfer coefficient and bulk temperature) which depend on the solution of the network analysis. This paper provides a detailed formulation of a one-dimensional model for steady, compressible flow inside a channel which is based on the solution of two equations for a coupled system of mass, momentum and energy equations with wall condensation. The model also accounts for channel area variation, inclination with respect to the engine axis, rotation, wall friction and external heating. The formulation was first validated against existing 1D correlation for an idealized case. The wall condensation is modeled using the best-suited film condensation models for pressure and heat transfer coefficient available in the literature and has been validated against the experimental data with satisfactory predictions.

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Experimental studies of the propagation of combustion in solids

Philosophical Transactions of the Royal Society of London Series A Physical and Engineering Sciences ◽

10.1098/rsta.1992.0044 ◽

1992 ◽

Vol 339 (1654) ◽

pp. 387-394 ◽

Cited By ~ 5

Keyword(s):

Heat Transfer ◽

Thermal Analysis ◽

Steady State ◽

Chemical Kinetics ◽

Profile Analysis ◽

Numerical Models ◽

Experimental Studies ◽

Dimensional Model ◽

Thermal Methods ◽

One Dimensional

The application of thermal methods to the study of steady-state combustion is described. Such methods provide a route to information on heat transfer and chemical kinetics which forms a basis for the implementation of numerical models. The experimental results from thermal analysis and temperature profile analysis have been examined within the context of a simple pseudo one-dimensional model of propagation offering some confirmation of the validity of the approach.

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Integrated modelling of internal combustion engine intake and exhaust systems

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1243/0957650011538622 ◽

2001 ◽

Vol 215 (4) ◽

pp. 495-506 ◽

Cited By ~ 6

Author(s):

O Chiavola

Keyword(s):

Internal Combustion Engines ◽

Gas Flow ◽

Complex Geometry ◽

Combustion Engine ◽

Internal Combustion ◽

Integrated Modelling ◽

Dimensional Model ◽

Three Dimensional Model ◽

One Dimensional ◽

Exhaust Systems

This paper presents a new method to analyse the unsteady gas flow in both intake and exhaust systems of internal combustion engines. Such a method is based on the simultaneous use of a one-dimensional model applied to describe the phenomena in ducts, together with a lumped parameter scheme to investigate the cylinder or other volume behaviour, coupled with a three-dimensional model, able to guarantee detailed information on flow behaviour in complex geometry, retaining the advantages of all methods, accuracy as well as fast processing and high flow pattern resolution. The description of the one-dimensional model developed with an example of its application is presented. The integrated approach with the coupling procedure is then described. Finally the results of a multicylinder exhaust system simulation are illustrated.

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One-dimensional model for heat transfer to a supercritical water flow in a tube

The Journal of Supercritical Fluids ◽

10.1016/j.supflu.2012.04.003 ◽

2012 ◽

Vol 68 ◽

pp. 1-12 ◽

Cited By ~ 7

Author(s):

Joost L.H.P. Sallevelt ◽

Jan A.M. Withag ◽

Eddy A. Bramer ◽

Derk W.F. Brilman ◽

Gerrit Brem

Keyword(s):

Heat Transfer ◽

Water Flow ◽

Supercritical Water ◽

Dimensional Model ◽

One Dimensional

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Numerical simulation of two-dimensional fins using the meshless local Petrov – Galerkin method

Engineering Computations ◽

10.1108/ec-07-2019-0340 ◽

2020 ◽

Vol 37 (8) ◽

pp. 2913-2938

Author(s):

Rajul Garg ◽

Harishchandra Thakur ◽

Brajesh Tripathi

Keyword(s):

Heat Transfer ◽

Numerical Simulation ◽

Experimental Investigation ◽

Two Dimensional ◽

Dimensional Model ◽

Content Type ◽

One Dimensional ◽

Mlpg Method ◽

Convection Model ◽

Good Agreement

Purpose The study aims to highlight the behaviour of one-dimensional and two-dimensional fin models under the natural room conditions, considering the different values of dimensionless Biot number (Bi). The effect of convection and radiation on the heat transfer process has also been demonstrated using the meshless local Petrov–Galerkin (MLPG) approach. Design/methodology/approach It is true that MLPG method is time-consuming and expensive in terms of man-hours, as it is in the developing stage, but with the advent of computationally fast new-generation computers, there is a big possibility of the development of MLPG software, which will not only reduce the computational time and cost but also enhance the accuracy and precision in the results. Bi values of 0.01 and 0.10 have been taken for the experimental investigation of one-dimensional and two-dimensional rectangular fin models. The numerical simulation results obtained by the analytical method, benchmark numerical method and the MLPG method for both the models have been compared with that of the experimental investigation results for validation and found to be in good agreement. Performance of the fin has also been demonstrated. Findings The experimental and numerical investigations have been conducted for one-dimensional and two-dimensional linear and nonlinear fin models of rectangular shape. MLPG is used as a potential numerical method. Effect of radiation is also, implemented successfully. Results are found to be in good agreement with analytical solution, when one-dimensional steady problem is solved; however, two-dimensional results obtained by the MLPG method are compared with that of the finite element method and found that the proposed method is as accurate as the established method. It is also found that for higher Bi, the one-dimensional model is not appropriate, as it does not demonstrate the appreciated error; hence, a two-dimensional model is required to predict the performance of a fin. Radiative fin illustrates more heat transfer than the pure convective fin. The performance parameters show that as the Bi increases, the performance of fin decreases because of high thermal resistance. Research limitations/implications Though, best of the efforts have been put to showcase the behaviour of one-dimensional and two-dimensional fins under nonlinear conditions, at different Bi values, yet lot more is to be demonstrated. Nonlinearity, in the present paper, is exhibited by using the thermal and material properties as the function of temperature, but can be further demonstrated with their dependency on the area. Additionally, this paper can be made more elaborative by extending the research for transient problems, with different fin profiles. Natural convection model is adopted in the present study but it can also be studied by using forced convection model. Practical implications Fins are the most commonly used medium to enhance heat transfer from a hot primary surface. Heat transfer in its natural condition is nonlinear and hence been demonstrated. The outcome is practically viable, as it is applicable at large to the broad areas like automobile, aerospace and electronic and electrical devices. Originality/value As per the literature survey, lot of work has been done on fins using different numerical methods; but to the best of authors’ knowledge, this study is first in the area of nonlinear heat transfer of fins using dimensionless Bi by the truly meshfree MLPG method.

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Quasi-One-Dimensional Modeling and Analysis of RBCC Dual-Mode Scramjet Engine

International Journal of Turbo and Jet Engines ◽

10.1515/tjj-2017-0055 ◽

2019 ◽

Vol 36 (2) ◽

pp. 195-206 ◽

Cited By ~ 2

Author(s):

Feng Cheng ◽

Shuo Tang ◽

Dong Zhang ◽

Yi Li

Keyword(s):

Heat Transfer ◽

Numerical Simulation ◽

Specific Heat ◽

Transonic Flow ◽

Wall Heat Transfer ◽

Dimensional Model ◽

Dual Mode ◽

One Dimensional ◽

Scramjet Engine ◽

Cfd Numerical Simulation

Abstract The quasi-one-dimensional method for the dual-mode scramjet (DMR) of the hypersonic RBCC powered vehicle was simplified in most of open researches. Furthermore, these simplified method can not fully capture the processes of wall heat transfer, changes in the boundary layer and the ratio of specific heat and the transonic flow in the reacting flow. Addressing this problem, we establish the models for processing core flow area, transonic flow and pre-combustion shock train (PCST) based on the governing equations for quasi-one-dimensional flow and certain assumptions. Thus the quasi-one-dimensional model of dual-mode scramjet engine that incorporates the changes in wall heat transfer and in the ratio of specific heat is built. Then, the reliability and accuracy of the model are assessed qualitatively and quantitatively by experiment and CFD numerical simulation. There is a high agreement between the theoretical calculations and the results of experimental data and CFD numerical simulation. This work expands the application scope and increases the reliability of quasi-one-dimensional model of dual-mode scramjet engine in RBCC engine. The results shed new light on the preliminary performance assessment and engineering application of dual-mode scramjet engine.

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