Analysis and investigation of the effect of ambient temperature change on the sound and outlet temperature of the air turbine jet engine test cell using the ejector pump method

A test cell is used to evaluate the performance of aerospace jet engines. In this study, an ejector pump model is employed to analyze the engine output nozzle flow. The interaction between the flow exiting the nozzle and the test cell augmentor is examined. The augmentor flow is calculated using thermodynamic equations, while key design parameters, including the exit temperature of the test cell and the noise generated by the exit jet velocity, are investigated. The results are obtained for an ambient temperature range of -15°C to 75°C. The lowest and highest ambient temperatures result in the maximum flow rate and outlet temperature. In the most critical condition, the exit jet velocity must not exceed 40 m/s, and the jet exit temperature should remain below 300°C. The Computational Fluid Dynamics (CFD) method is used to analyze gas dynamics and acoustics. ANSYS software is utilized for meshing, and Fluent commercial software is applied for the analysis. The maximum sound intensity at a distance of 3 meters from the engine is found to be 175 dB, while the maximum sound intensity outside the test cell is approximately 95 dB. Additionally, the flow velocity at the test cell exit remains below 40 m/s.