Simulation And Control Of The High Speed Transient Blade Wind Tunnel's Pneumatic Characteristics

The paper analyses the design theory of the high speed transient blade wind tunnel , studies characteristics of the tunnel's main parts systemic summarizes calculation methods of each part. This work will bring convenience for the future tunnel test and tunnel debugging and is important to the construction of similar tunnel.This paper has referred a lot of foreign literatures. We are going to analyze the gas resource, the pipeline, the ejector, the muffler, according to the configurations of this wind tunnel. The part of reservoir give the calculating method of quantity of the heat accumulating material and analyses the convection heat transfer .the part of tube prescribes the throttle character and the pressure regulation principal of the valve ,and calculating press lose of straight tube ,siphon and cross tube . The part of test section and ejector pump introduces calculating the mixing process of cooling flow and main flow in the passages of five turbine blades and the principal of ejector, the character of ejector, the critical traits of ejector. At last, it calculates the starting time of the tunnel.The control scheme of this wind tunnel has come true which can control enter gas pressure, experimental mach-number and elicited pressure according to the design of the wind tunnel, and the traits of the multi-nozzle ejector which will be used in our tunnel.At last, numerical simulation methods were used to predicting the surface heat transfer coefficients of NASA-MarkII and NASA-C3X guide vanes and calculated results is compared with experimental date. It shows that different turbulence models calculated results have significant difference, the same turbulence model's calculated results are different if using different near-wall treatment functions; some turbulence model's calculated results only are applicable to some area of the vane surface. Today, the modeling approaches developed for turbine blade are not adequate for predicting the wide rang of representative gas turbine airfoil-specific data used for verification. So, turbulence models and Near-wall treatment functions must be selected and modified carefully when it was applied into the practice. According to different computational domain and surface shape using the different turbulence model is the better way to simulate heat transfer.