The PD-8 engine for the SJ-100 aircraft, which will replace the SaM146, is currently undergoing a series of bench and flight tests. On 12 October, the propulsion system was launched for the first time as part of the aircraft. The Central Aerohydrodynamic Institute (TsAGI) is testing a half-model SJ-100 with nacelles and modified pylons for the PD-8.
At the first stage of tests, the team led by Alexander Lysenkov, deputy head of the department of aerodynamics of power plants of the Central Aerohydrodynamic Institute, developed a modification of the external contours of the engine pylon for the SJ-100 by means of numerical studies. The calculations were carried out using the EWT-CAGI software package developed at the institute. At the second stage, a model of the pylon was produced for testing in TsAGI wind tunnels. Experimental studies of the SJ-100 half-model took place in the T-128 transonic wind tunnel.
Several configurations of the “wing – nacelle – pylon” assembly were compared with the original, provided by PJSC “Yakovlev”, and the engine pylon modified at the Institute. During the tests, it was studied how, depending on the configuration of the propulsion system in a wide range of Mach numbers, the cruising aerodynamic characteristics of the aircraft change: lift, drag, and moment characteristics. Airflow visualisation was also carried out to study the streamline of its elements.
“During the tests, the modified pylon for the nacelle of the PD-8 engine confirmed its calculated aerodynamic characteristics,” TsAGI said.