ISRO's C20 cryogenic engine successfully passes critical test in ambient conditions
Dec 12, 2024
Sriharikota (Andhra Pradesh) [India], December 12 : The Indian Space Research Organisation (ISRO) has achieved a significant milestone with the successful testing of its C20 cryogenic engine under ambient conditions, featuring restart-enabling systems.
"ISRO achieves a major milestone! The C20 cryogenic engine successfully passes a critical test in ambient conditions, featuring restart-enabling systems--a vital step for future missions," ISRO posted on X on Thursday.
The space agency stated that during the test, both engine and facility performance were normal, with all required engine performance parameters achieved as expected.
On November 29, ISRO conducted the sea-level hot test of its CE20 cryogenic engine, which features a nozzle area ratio of 100. During this test, the performance of a multi-element igniter was also successfully demonstrated.
"ISRO successfully carried out the sea-level hot test of its CE20 cryogenic engine featuring a nozzle area ratio of 100 at the ISRO Propulsion Complex, Mahendragiri, Tamil Nadu, on November 29, 2024. The performance of a multi-element igniter, required for engine restart capability, was also demonstrated during this test," the space organisation said in a statement.
"Testing the CE20 engine at sea level presents considerable challenges, primarily due to the high area ratio nozzle, which has an exit pressure of approximately 50 mbar. The main concerns during sea-level testing include flow separation inside the nozzle, leading to severe vibrations and thermal issues at the flow separation plane, potentially causing mechanical damage to the nozzle. To address this issue, flight acceptance tests for CE20 engines are currently conducted at the High-Altitude Test (HAT) facility, adding complexity to the acceptance testing procedure," it added.
"To reduce the complexity of HAT testing, a sea-level test utilising an innovative Nozzle Protection System was devised. This has paved the way for a cost-effective and less complex procedure for acceptance testing of cryogenic engines," ISRO explained further.
ISRO also evaluated the multi-element igniter performance during this test.
"Restarting a cryogenic engine is a complex process, with major challenges including vacuum ignition without nozzle closure and the use of a multi-element igniter. ISRO has previously demonstrated vacuum ignition of the CE20 engine without nozzle closure in earlier ground tests. In this test, the performance of the multi-element igniter was also evaluated. Only the first element was activated, while the health of the other two elements was monitored," it said.
"During this test, both engine and facility performance were normal, and all required engine performance parameters were achieved as anticipated. The indigenous CE20 cryogenic engine, developed by ISRO's Liquid Propulsion Systems Centre, powers the upper stage of the LVM3 launch vehicle. It has been qualified to operate at a thrust level of 19 tonnes and has successfully powered the upper stage of six LVM3 missions. Recently, the engine was qualified for the Gaganyaan mission with a thrust level of 20 tonnes and further uprated to 22 tonnes for the future C32 stage, enhancing the payload capability of the LVM3 launch vehicle," ISRO added.
