Авіаційно-космічна техніка та технологія (Aug 2020)

INVESTIGATION INFLUENCE TEMPERATURE DISTRIBUTION IN THE MATRIX ON THE CHARACTERISTICS OF THE THERMOACOUSTIC APPARATUS

  • Владимир Владиславович Коробко

DOI
https://doi.org/10.32620/aktt.2020.5.12
Journal volume & issue
Vol. 0, no. 5
pp. 96 – 102

Abstract

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The problem of utilization of low-potential thermal emissions of the Power plants of industry, transport, energy, with the help of thermoacoustic energy-saving systems may be solved. Such systems are separate functional modules connected to the main power plan with transitional systems that provide energy exchange between external energy sources and thermoacoustic engines (TAE). These intermediate systems are circulating circuits, include external heat exchangers, for direct contact with energy sources, and internal, which are components of the thermoacoustic engine. Design features of thermoacoustic energy-saving systems define the use of recuperative heat exchangers of tubular-rib design with cross-movement of coolants. Known, that at the outlet of such heat exchangers, the coolants have a significantly inhomogeneous temperature distribution in the cross-sections. In this case, this will lead to the formation of inhomogeneous temperature distribution in the structural elements of the thermoacoustic transformation core of TAE, which is an unwanted phenomenon. Existing theoretical models of thermoacoustic and methods of calculation of TAE have built within the linear theory, which assumes the presence of a purely homogeneous distribution of thermophysical parameters in the cross-sections of any elements of TAE - resonators, heat exchangers, matrices, etc. The mathematical model of temperature distribution in the TAE matrix depending on the temperature field on the surface of heat exchangers of the TAE was developed. The peculiarity of the proposed model is taking into account the influence of the initial hydrodynamic stabilization of the flow on the intensity of heat transfer. Cases of using different types of intermediate coolants, such as water or thermal fluids, have been investigated. Numerical simulations have shown that the inhomogeneity of the temperature distribution in the cross-section of the TAE matrix leads to a decrease in the possible capacity of TAE by 1.1 to 1.4 times. The use of heat exchangers based on phase transitions in thermoacoustic energy-saving systems can reduce the level of temperature field inhomogeneity in the matrix, which will increase the efficiency of the thermoacoustic system.

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