The Indian Space Research Organisation (ISRO) has successfully completed a long-duration test of its PS4 engine, which has been re-engineered using advanced additive manufacturing (AM) techniques, commonly known as 3D printing. This breakthrough was achieved with the collaboration of Indian industry, ISRO announced on Friday.

The newly designed engine, now a single piece, offers remarkable efficiency improvements, saving 97% of raw materials and reducing production time by 60%. This milestone was marked by a successful hot test of the liquid rocket engine, which was manufactured using AM technology and operated for 665 seconds on May 9, according to an official release from ISRO.

The tested engine is the PS4 engine used in the upper stage of the Polar Satellite Launch Vehicle (PSLV). Traditionally, the PS4 engine has been manufactured using conventional machining and welding techniques, providing a thrust of 7.33 kN in a vacuum. It also serves in the Reaction Control System (RCS) of the first stage (PS1) of PSLV.

The engine utilizes earth-storable bipropellants, specifically Nitrogen Tetroxide as the oxidizer and Mono Methyl Hydrazine as the fuel, operating in a pressure-fed mode. This redesign was spearheaded by ISRO’s Liquid Propulsion Systems Centre (LPSC), which embraced the Design for Additive Manufacturing (DfAM) concept to achieve significant advantages.

The Laser Powder Bed Fusion technique used in manufacturing reduced the number of parts from 14 to a single piece and eliminated 19 weld joints. This resulted in substantial material savings, using only 13.7 kg of metal powder compared to the 565 kg of forgings and sheets required for conventional manufacturing processes. Additionally, production time was cut by 60%.

The engine’s manufacturing was carried out by WIPRO 3D, and the hot testing took place at the ISRO Propulsion Complex in Mahendragiri, Tamil Nadu. As part of the development program, the injector head of the engine was realized and successfully hot tested earlier. Detailed flow and thermal modeling, structural simulation, and cold flow characterization of the prototype hardware were conducted to ensure readiness for the hot test.

Four successful developmental hot tests of the integrated engine were conducted for a cumulative duration of 74 seconds, validating the engine’s performance parameters. The engine was then successfully tested for the full qualification duration of 665 seconds, confirming that all performance parameters met expectations.

ISRO plans to induct this additively manufactured PS4 engine into its regular PSLV program, marking a significant step towards more efficient and cost-effective space missions. This achievement underscores ISRO’s commitment to leveraging cutting-edge technologies to enhance its capabilities in space exploration.

By Impact Lab