Context: Recently, The Indian Space Research Organisation (ISRO) successfully conducted the hot test on a semi-cryogenic engine (SE2000), going a step closer to finalising the crucial cryogenic stage where powering the booster stages of launch vehicles is realised.
- This is the first hardware test for the development of semi-cryogenic engines.
- Scientifically, this test is known as the Power Head Test Article (PHTA).
- ISRO is developing a 2000 kilo-Newton (kN) thrust semi-cryogenic engine to enhance the payload capability of Launch Vehicle Mk III (LVM3).
PHTA
- Power Head Test Article, without the thrust chamber, has been successfully tested.
- PHTA is a significant precursor test to validate the integrated performance of some of the engine’s critical subsystems, such as the gas generator, turbo pumps, pre-burner and control components.
- The test involves performing hot-firing for an extremely brief duration of not more than 4.5 seconds.
Difference between Cryogenic engine and Semi-cryogenic engine
| Cryogenic engine | Semi-cryogenic engine |
| The cryogenic engine uses liquid oxygen and liquid hydrogen. | The semi-cryogenic engine uses a liquid oxygen (LOX) – kerosene combination. |
| Handling liquid hydrogen is challenging, it needs to be stored at minus 253 degrees Celius and | LOX – kerosenecombination offers advantages like high-density impulse (with respect to cryogenic). |
| Liquid hydrogen is highly inflammable. More expensive. | Kerosene being easily storable. Less toxic (with respect to storage). More cost-effectiveness. |
Development of NGLV
- The Next Generation Launch Vehicle (NGLV) is a heavy lift launch vehicle, which will replace the Polar Satellite Launch Vehicle (PSLV).
- The first and second stages will use Semi-cryogenic engines and the upper stage will be a cryogenic stage.
- It offers a maximum payload capability of 10 tonnes to Geostationary Transfer Orbit (GTO).
- It offers a maximum payload capability of 30 tonnes to Low Earth Orbit (LEO).
- It will be deployed for all the unmanned and manned Gaganyaan missions.
- NGLV is a human-rated launch vehicle offering both high payload capability and reusability (reusable first stage).
- Presently, NGLV is under development phase.