Research On Flow Development Law Of Inner Orifice Plate In Typical Intake Device

Orifice plate is a common structure in fluid machinery.It can be installed in the intake device of aeroengine test bed to simulate the specific distorted flow field.The flow around orifice plate interacts with other flow characteristics in the flow passage,which affects the flow structure and loss.In order to design this kind of orifice more accurately and efficiently,the flow mechanism of orifice under the influence of the structural parts in the intake device should be obtained.The flow development of orifice in a typical intake device and its influence on aerodynamic parameters are analyzed by combining numerical simulation with experiment.The main work includes the following aspects:The flow development law of orifice flow in the axial inlet passage is calculated and experimentally studied.Considering the influence of the structure of the axial inlet device,the causes of the formation of the low pressure zone behind orifice flow plate are analyzed by steady calculation,and the specific process of the flow development behind the orifice plate is described.The formation and development process of the eddy current behind the orifice plate is further analyzed by unsteady calculation.The influence of orifice plugging rate,number of orifices and size of calculation model on the flow in the axial intake device was studied comparatively.The development law of flow field along different cross sections was summarized.The similarity of flow parameters at the double diameter of the plate was verified by the test/test of the axial intake device.Three-dimensional steady full-channel numerical simulation of flow around orifice plate of radial intake device is carried out.The development law of original flow field without orifice plate is analyzed.It is found that support plate is the main source of flow loss in original flow field.The increase of plate number will increase additional flow loss,especially when Mach number is low,the increase of flow loss will be faster because of more support plate number.The influence of geometric structure change of intake orifice plate on flow is analyzed,and the numerical simulation and experiment are compared.The main loss source of radial intake device without orifice plate is the mixing flow loss between the wake area behind the supporting plate and the mainstream.The existence of supporting plates has little effect on the flow field heterogeneity,and the change of the number of supporting plates has no special effect on the flow field distortion.