Design and Operational Development a Pneumatic Braking System for a Gas-Turbine Units Test Bench

Each gas turbine engine must be tested after it has been produced or repaired. If the engine is used to generate power on the output shaft, its power must be utilized during the test process. To do this, pneumatic brake system can be applied. It allows to measure and utilize the power generated by the engine by using this power to drive a single compressor connected through the clutch with the output shaft of the engine under test. The process of gas-dynamic designing of the pneumatic braking system for a modernized gas-turbine engine NK-36ST is described in detail in this paper. Computational model was created by using Numeca Fine / Turbo and was verified using the experimental data of the baseline compressor. Also, research efforts which are aimed at improving the efficiency of the pneumatic braking system and increasing its gasdynamic stability were conducted. In particular, guide vane was added and the contours of its flow channel were modified. Also the exhaust nozzle was designed for the pneumatic braking system to ensure its work at the required operating points.