Variable mach number transonic rigid free jet nozzle

Abstract

The invention relates to a variable mach number transonic rigid free jet nozzle which comprises a left sidewall (1), a right sidewall (10), an upper support plate (4) and a lower support plate (5), wherein the left sidewall (1) and the right sidewall (10) are bilaterally symmetric, and are fixed and connected into an open nozzle frame in a supporting way by virtue of the upper support plate (4) and the lower support plate (5), which are symmetrically arranged; an upper molded surface mechanism (2) and a lower molded surface mechanism (3) are longitudinally and symmetrically arranged in the nozzle frame. The variable mach number transonic rigid free jet nozzle is characterized by also comprising an upper right semicircular bearing (6) and an upper left semicircular bearing (7). According to the variable mach number transonic rigid free jet nozzle, the pneumatic flow field is good, and a design method is reasonable; a semicircular shaft design is adopted for the tail end of a rigid molded surface, so that the area of an outlet of the open nozzle is kept constant, and an airflow field at the outlet of the nozzle is uniform and regular; an obvious uniform test area can be formed at the outlet of the nozzle, so that test requirements are met, and good effects are achieved in a high-altitude stand air blowing test.

Description

Technical field: [0001] Wind tunnel test or high-altitude platform aerodynamic test of aero-engine. Background technique: [0002] The free jet test is an important means of simulating the high-altitude inlet-engine matching test. The function of the air intake device is to make the air flow passing through the device reach the simulated Mach number, total pressure, Parameter conditions such as airflow angle. The free jet inlet device (referred to as the nozzle) is the core section to establish the free jet flow field, and its design quality directly determines the quality of the free jet flow field, determines the reliability and accuracy of the free jet test data, and determines the The test capability of the free jet and the operating efficiency of the cabin are improved. [0003] The transonic nozzle adopts a shrinking and expanding structure. In the contraction section, the airflow is uniformly accelerated from the low-pressure sound velocity to the sonic velocity, an...

AI Technical Summary

Problems solved by technology

However, due to the limitation of the Mach number adjustment range of the rigid nozzle and the continuous adjustment structure of the Mach number, its research is relatively lacking. Existing rigid nozzles have a rectangular section of the nozzle outlet to varying degrees, which is difficult to guarantee, the test Mach number range is limited, and the deformation of the rigid panel Defects such as poor repeatability

Images