Abstract
In this paper, a study of gasdynamic processes that occur in a low-flow aerothermopressor has been done. The aerothermopressor is a two-phase jet apparatus for contact cooling, in which, due to the removal of heat from the air flow, the air pressure is increased (thermogasdynamic compression) and its cooling is taken place. Highly effective operation of the aerothermopressor is influenced by primarily the flow part design and the water injected method in the apparatus. Constructive factors that influence energy costs to overcome friction losses and local resistances on the convergent-divergent sections of the aerothermopressor are exerted a significant impact on the working processes in the apparatus. In this paper, a study of a number of typical low-flow aerothermopressor models has been conducted by using computer CFD modeling. Determination of the main parameters of the air flow (total pressure, dynamic pressure, velocity, temperature, etc.) has been carried out for a number of taper angles of a confuser a and a diffuser b, as well as for a number of values of the relative air velocity in the working chamber M = 0.4-0.8. Comparison of the obtained data with experimental data has been carried out. The deviation of the calculated values of local resistances coefficients in the confuser and in the diffuser from those obtained by computer CFD modeling does not exceed 7–10%. The recommended angles were determined: confuser convergent angle – 30° and diffuser divergent angle – 6°, corresponding to the minimum pressure loss is 1.0 – 9.5 %, and therefore also to the maximum pressure increase as a result of the thermogasdynamic compression that occurs during injection and evaporation of liquid in the working chamber. Thus, analytical dependences are obtained for determining the local resistance coefficients for the confuser (nozzle) and the diffuser, which can be recommended to use in the design methodology for low-flow aerothermopressors.
Publisher
Odessa National Academy of Food Technologies
Subject
Applied Mathematics,General Mathematics
Reference16 articles.
1. 1.The empirical equations for determining the co-efficients of local resistance of the confuser cand diffuser dof the low-flow aerothermopressor are determined. The given results correspond to the fol-lowing mode and geometrical characteristics 1.2 · 1052. 2.The numerical values of local resistance coeffi-cients was determined by using computer CFDmodel-ing at M=0.4-0.8: c=0.02-0.08 and d=0.08-0.32.
3. 3.The recommended angles were determined: confuser convergent angle =30°and diffuser di-vergent angle =6°, corresponding to the minimum pressure loss Ploss=1.0-9.5%, and therefore also to the maximum pressure increase as a result of the thermogasdynamic compression that occurs during injection and evaporation of liquid in the working chamber.References1.Konovalov D.V., Kobalava H.O. (2018). Contact air cooling by using the aerothermopressor in the gas turbine plant cycle. Refrigeration Engineering and Technology. 54(5), pp. 62-67.DOI:https://doi.org/10.15673/ret.v54i5.12482.Konovalov D.V.(2011). Termopresorni systemy okholodzhennia sudnovykh DVZ. Aerospace Technic and Technology. 10(87), pp. 44-48.http://nti.khai.edu:57772/csp/nauchportal/Arhiv/AKTT/2011/AKTT1011/index.htm3.Zhivica V.I.(2002). Promezhutochnye ohladiteli s termopressorom dlja dvuh stupenchatyh amiachnyh holodil'nyh ustanovok. Holodil'naja tehnika. 5, pp.18-20.
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