Numerical Research Of Rotational Flow Field In Base Bleed Unit

In this paper, the numerical simulation and engineering experiment methods were combined to study the base bleed unit. The static burning rate model and rotation burning rate model were established based on the combustion characteristics of the base bleed propellant. To get the inner flow field of the base bleed unit by using numerical simulation, and experiments have been carried out to study the combustion of the propellant inner the unit. A comparative analysis of numerical simulation and engineering experiment was made.Firstly, starting from the assumption chemical formula of propellant components, and getting the total assumption chemical formula. A computer program based on energy conservation equation and mass conservation equation combined with chemical equilibrium was developed to solve the thermodynamic parameters of the combustion products, and compared with NASA-CEA.Secondly, it is very important to get burning rate formula in calculating inner flow field. To get the static burning rate formula with least square method. Under the condition of rotation, to get the rotation burning rate formula with heat transfer enhancement method. The rotation burning rate formula is related with static burning rate and burning radius and rotational speed. Through numerical simulation, the combustion flow field is visible.Last, computing platform of ANSYS Fluent was used to calculate the combustion flow field of the unit, the mass flow inlet UDF and the moving burning surface UDF were created. Many pressure-time curves of different rotational speed were gotten through base bleed ground test. Pressure-time curves of calculation simulation and engineering experiment are contrastively discussed and analyzed.The results show that:pressure-time curves of calculation simulation and engineering experiment showed a similar trend. The data of calculation simulation coincides with the data of engineering experiment very well. The working process of the base bleed unit has been more accurately reflected by the calculation simulation, the heat transfer enhancement model can be used to forebode the working process. The theory and achievements of this paper have reference value for the design of base bleed.