Aft-Body Jet Effects Testing Technique Based on Cassette Strain Gauge Balance in Wind Tunnel

The exhaust flow induced by aft-body nozzle of hypersonic aircraft with the aerodynamic characteristics of the vehicle dramatically, and the wind tunnel jet simulation aerodynamic test is an important method to investigate such interaction effect. It’s common to use bar strain gauge balance for wind tunnel test. The balance is located inside the aircraft model and takes up a large amount of space in the model cavity, which makes it difficult to design nozzle and gas pipeline of the model. In order to meet the requirements of large flow and high pressure jet experiments, a new aft-body jet effects testing technique based on cassette strain gauge balance is proposed. The principle of the technique is to replace the measuring component from a bar balance to a cassette balance, while the cassette balance is located outside the model so that there is enough space in the model cavity to design the gas pipeline. In order to prove the feasibility of the test technique, wind tunnel experiments were carried out. The results indicate that the application of the technique can obtain a stable jet, and the maximum difference of the jet is 0.29%. The technique can be applied to high temperature and high pressure environment and has a wide range of adaptability. The technique can be used to capture the effect aft-body jet aircraft on aerodynamic characteristics effectively and dynamically, with the maximum difference between different tests is 0.51%. The method is suitable for wind tunnel test.