Begell House Inc.
Heat Transfer Research
HTR
1064-2285
37
3
2006
Study of Radiative and Conductive Heat Transfer by the Inverse Problem Method
189-198
Aleksey V.
Nenarokomov
Department of Space System Engineering, Moscow Aviation Institute (Aerospace University), Volokolamskoe Shosse 4, Moscow 125993, Russia
Dmitry M.
Titov
Moscow Aviation Institute, 4 Volokolamskoe Hgw., Moscow, 125993, Russia
To create new heat-protective materials, a rather large scope of comparative thermal tests is performed so as to analyze heat-protective properties of materials under different heating conditions correspondent to the operating conditions. To identify mathematical models of heat transfer in modern structural, heat-protective, and heat-insulation materials, this work proposes a method based on the solution of coefficient inverse heat-condition problems.
Development of an Improved Mode of Heat Transfer of a Hydrocarbon Heat Carrier under a Supercritical Pressure in an External Acoustic Field of a Standing Wave Formed by Thermoacoustic Self-Oscillations of Pressure
199-210
Ch. M.
Verdiev
Azerbaijan State Oil Academy, Baku, Azerbaijan
D. Ch.
Verdiev
Azerbaijan State Oil Academy, Baku, Azerbaijan
The data on experimental investigation and calculation of the local coefficient of heat transfer of toluene, which, in the case of mixed convection and at a supercritical pressure, flows in small-diameter vertical tubes (d = 3−4 mm) at a constant heat flux on the wall (a descending flow) are presented. Experiments were carried out in the field of convective heat transfer accompanied by generation of high-frequency pressure oscillations of a heat carrier. It has been established that high-frequency pressure oscillations represent standing pressure waves. It is shown that the distribution of the wall temperature and of the heat-transfer coefficient over the tube length depends on the local distribution of pressure in a standing wave. The boundary of the beginning of thermoacoustic oscillations has been found.
Hydrodynamics and Heat Transfer in Slit Gaskets with Magnetic Seals
211-220
A. N.
Vislovich
Belarusian State Technological University, Minsk, Belarus
A. S.
Dmitrichenko
Belarusian State Technological University, Minsk, Belarus
We present the results of a theoretical and experimental investigation into the conditions of the dynamic and thermal equilibrium of a magnetic liquid in a combined (magnetoliquid and slit) gaskets.
Models and Methods of Semi-Infinite Optimization Inverse Heat-Conduction Problems
221-232
E. Ya.
Rapoport
Samara State Technical University, Samara, Russia
Yu. E.
Pleshivtseva
Samara State Technical University, Samara, Russia
A broad range of inverse heat-conduction problems in their extreme statement, which are reduced to problems of optimum control by the corresponding system with distributed parameters, is analyzed. Parameterization of desired control actions by means of necessary extre-mum conditions is used for performing the procedure of accurate reduction to a special class of non-smooth finite-dimensional problems of mathematical programming, formulated in terms of the functions of a maximum.A computational algorithm for finding the solutions of these problems is proposed; this algorithm is based on alternance properties of the sought-for extremales, similar to analogous results in the theory of nonlinear Chebyshev approximations and on the a priori information on the characteristics of the analyzed functions of a maximum, dictated by the knowledge of the subject domain of the investigated problem. Possibilities of the proposed method are demonstrated by examples of solution of typical problems of optimum control, optimum design, and identification of thermophysical processes.
Axisymmetrical Problem of Accumulation of Heat Based on Phase Transition
233-246
I. I.
Rozhin
Institute of Oil and Gas Problems, Siberian Branch of the Russian Academy of Sciences, Russia
An axisymmetrical problem of accumulation of heat in the material, going through phase transition in interaction with the heat carrier at a cyclically varying temperature is analyzed. The stated two-dimensional differential problem has been solved by the method of splitting using the integration-interpolation balance and sweep algorithms with simple iteration. Temperature fields for laminar and turbulent modes of heat carrier flow have been compared. The survey has demonstrated that turbulent conditions are most optimal in terms of heat accumulation.
Experimental Investigation of Heat Transfer along the Length of a Horizontal Tube during Liquid Metal Heat-Carrier Flow in a Transverse Magnetic Field
247-258
L. G.
Genin
Moscow Power Institute (Technical University), 14 Krasnoarmeiskaya str., Moscow, 111250, Russia
Vyacheslav G.
Zhilin
Incorporated Institute of High Temperatures (IIHI) of the Russian Academy of Science, 13/19 Igorskaya str., Moscow, Russia
Yurii P.
Ivochkin
Moscow Power Engineering Institute; and Joint Institute for High Temperatures of the Russian Academy of Sciences, Moscow, Russia
Ya. I.
Listratov
Moscow Power Institute (Technical University), 14 Krasnoarmeiskaya str., Moscow, 111250, Russia
N. G.
Razuvanov
Joint Institute for High Temperatures of the RAS, 125412 Izhorskaya st. 13 Bd.2, Moscow, Russia; National Research University "MPEI", 111250, Krasnokazarmennaya st. 14, Moscow, Russia
R. A.
Sarvin
Moscow Power Engineering Institute (Technical University), Moscow, Russia
V. G.
Sviridov
Joint Institute for High Temperatures of the RAS, 125412 Izhorskaya st. 13 Bd.2, Moscow, Russia; National Research University "MPEI", 111250 Krasnokazarmennaya st. 14, Moscow, Russia
Liquid metal flow heat transfer in a heated horizontal tube in longitudinal and transverse magnetic fields was investigated on an experimental MHD complex of the Moscow Power Engineering Institute and Institute for High Temperatures of the Russian Academy of Sciences. The flow conditions model those present in a tokamak fusion reactor. Detailed measurements of the temperature fields and of the heat transfer coefficients were performed over the entire length of the tube section heated.
Heat Exchangers with Flow Swirling by Twisted Tubes and Estimation of Their Thermohydraulic Efficiency
259-270
Boris V.
Dzyubenko
Moscow Aviation Institute (State Technical University), 4 Volokolamskoe Highway, Moscow, 125993, Russia
Guenrikh A.
Dreitser
Department of Aviation-Space Thermal Techniques,
Moscow Aviation Institute, Volokolamskoe shosse, 4, Moscow, 125993, Russia
A. I.
Yakimenko
Moscow Aviation Institute (State Technical University), Moscow, Russia
Heat-exchange apparatuses forming part of power plants, production lines, and various-purpose processes, may constitute, by their mass and overall dimensions, a significant fraction of the total mass of the entire equipment. Therefore, there arises the necessity to enhance heat transfer in such apparatuses and to increase their output parameters. Among the well-known methods of heat-transfer enhancement a special place is occupied by the method of flow swirling by twisted tubes which ensures heat-transfer enhancement in both flow past banks of tubes and flow inside twisted tubes. Dense packing of twisted tubes in a bank with the tubes contacting at some points (at a maximum dimension of the tube profiles), allows one to create a more compact heat exchanger than in the case of round tubes as well as to ensure its vibration strength.
Investigation of the Frequency Spectra of Pulsations in a Gas Tube Flow under Unsteady Conditions
271-278
Guenrikh A.
Dreitser
Department of Aviation-Space Thermal Techniques,
Moscow Aviation Institute, Volokolamskoe shosse, 4, Moscow, 125993, Russia
V. M.
Kraev
Moscow State Aviation Institute (Technical University), Moscow, Russia
Data on the structure of a turbulent gas flow in a round tube under isothermal and nonisothermal conditions of flow were obtained experimentally. The data are used to calculate the frequency spectra of axial and radial velocity fluctuations. An analysis of the effect of nonisothermicity on the mechanisms underlying the incipience and development of turbulent pulsations is carried out.