Abstract:

The flow field in afterburner diffuser of a turbofan engine is calculated by the SIMPLE method. The results are compared well with the measured data. It is illustrated that the characteristics of the flow field in the diffuser can be investigated by means of computational methods.The computation shows that the profiles of axial inlet velocity component and the values of inlet turbulent energy have a considerable effect on the flow field in the diffuser. Therefore, in model or component tests it is necessary to guarantee the identity of the axial velocity profiles and the values of turbulent energy at the inlet of the test unit with those in the corresponding position of the actual engine. The variation of flow field with velocities of the engine on the ground and in flight is researched by the present method. It is shown that the bypass ratio is the primary cause of the variation of the flow field.