Tham khảo tài liệu 'developments in heat transfer part 13', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 470 Developments in Heat Transfer All temperature curves were obtained for all the pressure cases and then an axisymmetric heat conduction numerical calculation was conducted to obtain the hot-gas-wall heat flux for each pressure case. Inspection of empirical heat transfer correlations available in the literature such as the Bartz Bartz 1957 all the heat flux data were scaled by 1 p0 8 and the results are shown in . It can be seen that all the heat flux distribution curves collapse to a single profile and all the cases show the same qualitative distribution trends and the almost same quantitative local values which means that the heat flux q of a gas-gas injector combustor correlates well with the pressure p as q p s . A valuable suggestion can thus be drawn that the heat flux data at high pressure condition can be predicted from that at a low pressure condition. Fig. 17. Thermocouple temperature traces representative for a test Fig. 18. Wall temperature versus axial distance for chamber pressure 471 Method for Measurement of Single-Injector Heat Transfer Characteristics and Its Application in Studying Gas-Gas Injector Combustion Chamber Fig. 19. Heat flux scaled with respect to 1 Pc0-8 versus axial distance for each chamber pressure case Numerical study In order to investigate the heat transfer characteristics at the high pressure condition unavailable in the experimental hot-test and further examine the inner combustion flowfields at different chamber pressures numerical simulations were conducted on this combustion chamber. Numerical models A great effort has been made to perform the CFD simulation of gas-gas combustion flow at Pennsylvania State University NASA Marshall Space Flight Center University of Michigan and Beihang University et al. Foust et al. 1996 Schley et al. 1997 Lin et al. 2005 Tucker et al. 2007a 2008b Cai et al. 2008 Sozer et al. 2009 Wang 2009a 2010b 2010c And the results indicated that the steady Reynolds .
