Abstract
An air jet distortion generation system is developed to simulate the distorted flow field ahead of gas turbine engines in ground test facility. The flow field of a system of four jets arranged circumferentially and issuing into a confined counterflow was studied experimentally and numerically. The total pressure distortion parameters were evaluated at the Aerodynamic Interface Plane (AIP) for several values of mass flow ratios. Since the total pressure loss distribution at theAIPis characteristically “V” shaped, the number of jets was increased to obtain total pressure distributions as required for gas turbine engine testing. With this understanding, a methodology has been developed to generate a target total pressure distortion pattern at theAIP. Turbulent flow computations are used to iteratively progress towards the target distribution. This methodology was demonstrated for a distortion flow pattern typical of use in gas turbine engine testing using twenty jets, which is a smaller number than reported in the literature. The procedure converges with a root-mean-square error of 3.836% and is able to reproduce the target pattern and other distortion parameters.
Highlights
The performance of a modern fighter aircraft is heavily influenced by the performance of its propulsion system
The compressors are designed for uniform inlet flows and suffer from performance degradation due to nonuniform inflow conditions leading the compressor to aerodynamic instabilities like rotating stall and surge
The overall total pressure loss and the total pressure distortion characteristics at the Aerodynamic Interface Plane (AIP) are discussed
Summary
The performance of a modern fighter aircraft is heavily influenced by the performance of its propulsion system. These aircraft perform high angle of attack and high angle of sideslip maneuvers, which puts severe demand on the gas turbine engine. The engine compression system is vulnerable to nonuniform or distorted flow in the inlet duct. The distortion in the inlet flow field can be in static or total pressures or temperatures or velocities. The total pressure distortion is the most common type and has the most deleterious effect on the performance of the compression system. The total pressure distortion profiles such as those occurring at flight conditions are termed “complex” (or “composite”) distortion patterns and can have both circumferential and radial nonuniformities
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
