Vikram Sarabhai Space Centre gets a new trisonic wind tunnel

‘Trisonic’ refers to the tunnel’s capability to test in three speed regimes; till now, the space agency relied on a similar facility at the NAL in Bengaluru

ISRO chairman S. Somanath and senior officials of the space agency inspect the trisonic wind tunnel at the Vikram Sarabhai Space Centre. | Photo Credit: Special Arrangement

The new trisonic wind tunnel at the Vikram Sarabhai Space Centre (VSSC) was inaugurated on Thursday by conducting the first blow-down test successfully.

The massive structure, which can perform tests in three speed regimes, equips the Indian Space Research Organisation (ISRO) with a robust in-house support system for space missions. For the country as a whole, it is a big step towards self-reliance in the aerospace sector, the VSSC says.

Wind tunnels are devices used to study the effects of air flows on solid objects—in this case, scale models of ISRO rockets and spacecraft. The trisonic wind tunnel at VSSC is about 160 metres long and measures 5.4 metres at its widest part.

The blow down was switched on by ISRO chairman S. Somanath.

In a ‘blow down test’, stored gases are released and blown through the tunnel’s test section, simulating flight conditions. The tunnel can simulate flight conditions from 0.2 times the speed of sound (68 metres per second) to four times the speed of sound (1,360 metres per second), according to the space agency.

‘Trisonic’ refers to the tunnel’s capability to test in three speed regimes—below the speed of sound (subsonic), at the speed of sound (transonic), and above the speed of sound (supersonic). Its parts include air storage vessels, a settling chamber where the airflow is ‘smoothened’ out, and nozzles for releasing the air into the test section.

The layout of the trisonic wind tunnel | Photo Credit: Special Arrangement

Senior ISRO officials including VSSC director S. Unnikrshanan Nair, Liquid Propulsion Systems Centre (LPSC) director V. Narayanan, and ISRO Inertial Systems Unit (IISU) director Sam Dayala Dev also witnessed the test.

The trisonic wind tunnel was implemented through M/s Tata Projects India Ltd with the assistance of industries across the country.

For years, ISRO had depended on the trisonic wind tunnel at the National Aerospace Laboratory (NAL), Bengaluru. The VSSC is already equipped with a hypersonic wind tunnel for testing parameters of re-entry missions. Commissioned in 2017, this tunnel can simulate flow speeds up to Mach 12.