The experimental study focuses on the heat flux on a double cone blunt body in the presence of tangential-slot super- sonic injection into hypersonic flow. The tests are conducted in a contoured axisymmetric nozzle wi...The experimental study focuses on the heat flux on a double cone blunt body in the presence of tangential-slot super- sonic injection into hypersonic flow. The tests are conducted in a contoured axisymmetric nozzle with Mach numbers of 7.3 and 8.1, and the total temperature is about 900 K. The injection Mach number is 3.2, and total temperature is 300 K. A constant voltage circuit is developed to supply the temperature detectors instead of the normally used constant current circuit. The schlieren photographs are presented additionally to visualize the flow and help analyze the pressure relationship between the cooling flow and the main flow. The dependence of the film-cooling effectiveness on flow parameters, i.e. the blow ratio, the convective Mach number, and the attack angle, is determined. A semi-empirical formula is tested by the present data, and is improved for a better correlation.展开更多
The flow field and heat transfer of the strip surface due to the twin slot vertical jet impingement were investigated using the ANSYS FLUENT.The RNG k-ε model was carried out in the turbulent calculation.Systematic p...The flow field and heat transfer of the strip surface due to the twin slot vertical jet impingement were investigated using the ANSYS FLUENT.The RNG k-ε model was carried out in the turbulent calculation.Systematic parametric research was conducted by varying the jet velocity of nozzle exit(V=5 m/s,7.5 m/s,10 m/s),the temperature of cooling water(T_w=280 K,300 K),the normalized spacing from the nozzle to the strip surface(H=10,15,20,33),and the normalized spacing from the nozzle to nozzle centerline(W=0,15,30).The velocity streamline of the flow domain and the general trend of the distribution of the local Nusselt number on the impingement surface of strip were obtained.The result indicate that,the average Nusselt number increases by about70%(90%) as the jet velocity is increased from 5 m/s to 7.5 m/s(from 7.5 m/s to 10 m/s),and T_w,Hand//have minimal effect on it.While the valley Nusselt number decreases by about 10%-43%with the increase of H and W.The functional relationship between the average Nusselt number and the systematic parameters is derived by the least square regression method.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11172326)the Scientific Research Program of National University of Defense Technology,China(Grant No.0100010112001)
文摘The experimental study focuses on the heat flux on a double cone blunt body in the presence of tangential-slot super- sonic injection into hypersonic flow. The tests are conducted in a contoured axisymmetric nozzle with Mach numbers of 7.3 and 8.1, and the total temperature is about 900 K. The injection Mach number is 3.2, and total temperature is 300 K. A constant voltage circuit is developed to supply the temperature detectors instead of the normally used constant current circuit. The schlieren photographs are presented additionally to visualize the flow and help analyze the pressure relationship between the cooling flow and the main flow. The dependence of the film-cooling effectiveness on flow parameters, i.e. the blow ratio, the convective Mach number, and the attack angle, is determined. A semi-empirical formula is tested by the present data, and is improved for a better correlation.
基金Project(2012 BAF04B01)Supported by the National Science and Technology Pillar Program during the Twelfth Five-year Plan of China
文摘The flow field and heat transfer of the strip surface due to the twin slot vertical jet impingement were investigated using the ANSYS FLUENT.The RNG k-ε model was carried out in the turbulent calculation.Systematic parametric research was conducted by varying the jet velocity of nozzle exit(V=5 m/s,7.5 m/s,10 m/s),the temperature of cooling water(T_w=280 K,300 K),the normalized spacing from the nozzle to the strip surface(H=10,15,20,33),and the normalized spacing from the nozzle to nozzle centerline(W=0,15,30).The velocity streamline of the flow domain and the general trend of the distribution of the local Nusselt number on the impingement surface of strip were obtained.The result indicate that,the average Nusselt number increases by about70%(90%) as the jet velocity is increased from 5 m/s to 7.5 m/s(from 7.5 m/s to 10 m/s),and T_w,Hand//have minimal effect on it.While the valley Nusselt number decreases by about 10%-43%with the increase of H and W.The functional relationship between the average Nusselt number and the systematic parameters is derived by the least square regression method.