High Enthalpy Shock Tunnel (HIEST) |
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Re-entry vehicles and space planes are exposed to gases with temperatures
higher than 10,000 degree Celsius when they travel at 4 to 7 km/sec
since the air around the vehicle is extremely compressed and heated.
HIEST is designed to produce such a hyper velocity test flow on the
ground. The HIEST is the world's larget and most efficient.
HIEST produces a test flow of maximum stagnation enthalpy of 25
MJ/kg and maximum stagnation pressure of 150 MPa to simulate dissociation
of molecules in the re-entry flight path of HOPE. This feature allows
test of a model of the re-entry vehicle as large as 50cm. HIEST also
enables test of a Scram jet model with a maximum length of 2.5 meters
at a dynamic pressure of up to 50 kPa.
Re-entry vehicles and space planes are exposed to gases with temperatures
higher than 10,000 degree Celsius when they travel at 7Km/sec since
the air around the vehicle is extremely compressed and heated. At
such high temperatures,oxygen and nitrogen molecules are dissociated
to their respective atoms. This alters the aerothermodynamic properties
of the flow around the vehicles. Such dissociation also drastically
affects combustion characteristics of the SCRAM jet engine, which
is expected to attain high performance as a result of its air breathing
system. HIEST is designed to produce a similar hyper velocity test
flow on the ground. HIEST produces a test flow of maximum stagnation
enthalpy of 25MJ/kg and maximum stagnation pressure of 150MPa to
simulate dissociation of molecules in the re-entry flight path of
HOPE. This feature allows test of a model of the re-entry vehicle
as large as 50cm. HIEST also enables test's of a SCRAM jet model
with a maximum length of 2.5m at a dynamic pressure up to 50KPa.

High Enthalpy Shock Tunnel (HIEST)

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The high enthalpy shock tunnel HIEST is the largest free-piston
shock tunnel in the world. The length and mass of the tunnel are
approximately 80m and 300ton, respectively. The picture above shows
the tunnel general view. From upstream, a secondary air reservoir,
a compression tube, a shock tube, and a test section are aligned.
Aerodynamic heat test using subscale model of HYFLEX
HYFLEX model is set in the HEK test section to measure aerodynamic
heat flux into the body due to friction between extremely high speed
flow and the body during hypersonic flight.
Main Characteristics

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- Air current speed: 4 to 7 km/sec
- Maximum stagnation temperature: 10,000 degrees To(K)
- Maximum stagnation pressure: 150 Po (MPa)
- Test time: 2.0 or more T (msec)
- Nozzle exit diameter: 120 cm (Maximum of 50 cm length of scale
model can be tested)
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