Public Affairs Department
Japan Aerospace Exploration Agency (JAXA)
Marunouchi Kitaguchi Building,
1-6-5, Marunouchi, Chiyoda-ku, Tokyo 100-8260
Japan
TEL: +81-3-6266-6400
March 20, 2006
Commissioning of Scramjet Combustor Flight Experiment
The Japan Aerospace Exploration Agency (JAXA) has undertaken research
into scramjet engines, which are one of the leading candidates for
next-generation space transportation propulsion systems, since 1987.
JAXA has developed a proprietary scramjet combustor and has
commissioned Australia’s University of Queensland to perform a flight
experiment with the combustor on 28 March 2006 (until 31 March 2006,
if required).
The aim of the experiment is to obtain experimental data in a real
flight environment for a scramjet combustor with an advanced fuel
injector (hypermixer injector to generate streamwise vortices)
developed by JAXA. The data will be compared with the results of
ground tests performed in the HIEST high-enthalpy shock tunnel
facility. The scramjet combustor is mounted on the front of a small
sounding rocket and accelerated to a speed close to Mach 8 for the
experiment. During the experiment, which will last approximately six
seconds, internal pressure data for the combustor is recorded.
This flight experiment will benefit the development of future space
transportation systems as outlined in JAXA’s long-term vision and
provide a valuable contribution to ongoing aerospace vehicle
development.
Experiment Contractor: The University of Queensland, Australia
Experiment Location: Woomera Test Range, Australia
Experiment Date: 28 March 2006 (until 31 March 2006, if required)
Experiment Lead: The University of Queensland, Australia
Department in charge at JAXA: Combined Propulsion Research Group,
Institute of Aerospace Technology (IAT)
SUPPORTING INFORMATION
Figure 1: Scramjet combustor installed in rocket nose
http://www.jaxa.jp/press/2006/03/20060320_ramjet_e.html#pic01
Figure 2: Rocket launch and flight sequence
http://www.jaxa.jp/press/2006/03/20060320_ramjet_e.html#pic02
[NOTE:
Additional images are available at
http://www.uq.edu.au/news/press/press-gallery.php
Video footage of the liftoff are available at
http://www.omc.uq.edu.au/video/hyshot/hyshot4.mov
http://www.omc.uq.edu.au/video/hyshot/liftoff.mov
http://www.omc.uq.edu.au/video/hyshot/HyShot3.mov
GLOSSARY
- Scramjet Engine
A SCRamjet (Supersonic Combustion Ramjet) is an engine being researched
for use in aircraft or future space transportation systems that operates
at high speeds of approximately Mach 4 (4 times the speed of sound) or
above.
While typical jet engines compress air with a multi-bladed rotating fan
before it enters the combustion chamber, at flight speeds above about
Mach 3, the air entering the engine can be compressed under its own
momentum by simply narrowing the area of the flowpath in the downstream
direction and a complicated construction is unnecessary. A jet engine for
supersonic aircraft that uses this method is called a ramjet.
When a ramjet is operated at low speed, the flow through the engine slows
to speeds below Mach 1 (subsonic flow). However, as the flight speed
increases, the temperature and pressure of the incoming air into the
combustor increases greatly and the engine performance suffers. To
avoid this problem, at speeds above Mach 4, it is better to not slow down
or compress the incoming air very much and perform combustion above
the speed of sound (supersonic flow). Ramjets of this type are called
Scramjets.
- Hypermixer Fuel Injector to Generate Streamwise Vortices
In the combustor of a scramjet engine, it is necessary to perform mixing
and burning of the fuel and air in an extremely short period of time
(0.5 milliseconds = five 10,000ths of a second) while maintaining
supersonic flow conditions.
Turbulent mixing of the fuel and air by the vortices present in the air
is the most ideal mixing method, however, at supersonic flight speeds,
the mixing of the fuel and air is reduced due to the strong suppression
of vortex [1] generation by the compressibility of the air flow. For this
reason, the promotion of supersonic mixing and combustion is one of
the key topics in scramjet research and it is being researched and
developed around the world. One of the most promising methods for
promoting supersonic mixing is the use of streamwise vortices
(vortices that rotate in a direction parallel to the main flow direction).
Research at JAXA has shown that the generation and control of vortex
parameters (size, strength, distribution, rotational direction etc.) in
supersonic flow is easier to accomplish with streamwise vortices than
with transverse vortices. Based on the results of this research, JAXA
has developed a hypermixer fuel injector that is able to efficiently and
quickly generate large-scale strong streamwise vortices with little
energy loss.
The HyShot-IV flight experiment will conduct an experiment under real
flight conditions using a scramjet combustor installed with a wall-mounted
hypermixer fuel injector to acquire combustor data in supersonic
combustion mode.
[1] In particular, transverse vortices (vortices that rotate in a
direction perpendicular to the main flow direction).
Public Affairs Department
Japan Aerospace Exploration Agency (JAXA)
Marunouchi Kitaguchi Building,
1-6-5, Marunouchi, Chiyoda-ku, Tokyo 100-8260
Japan
TEL: +81-3-6266-6400
March 30, 2006
Flight Test Results for Scramjet Engine
The Japan Aerospace Exploration Agency (JAXA) performed a scramjet
engine flight test [2] using the HyShot flight experiment system [1]
at the Woomera range in Australia at 11:40 a.m. on March 30, 2006
(Japan Standard Time, JST [0240 UTC]) The actual flight test operations
were commissioned to the University of Queensland (UQ) in Australia.
JAXA is currently waiting for the test results from the UQ and will
inform you of the results as soon as we receive them.
[1] The HyShot flight experiment system is a test system of the UQ
that uses a small sounding rocket (Terrier-Orion Mk70) of the National
Aeronautics and Space Administration (NASA.) The purpose of the flight
test this time is to acquire data including pressure distribution data
in the engine for six seconds under an accelerated condition up to
approx. Mach 8, utilizing the scramjet engine which was independently
researched and developed by JAXA. It was loaded on top of the rocket
and launched for the test.
[2] For more details about the scramjet engine test, please refer to
the press release on March 20, 2006,
http://www.jaxa.jp/press/2006/03/20060320_ramjet_e.html
Launch Photo: HyShot-IV launch moment (11:40 at March 30, 2006)
http://www.jaxa.jp/press/2006/03/20060330_ramjet_e.html#pic
Public Affairs Department
Japan Aerospace Exploration Agency (JAXA)
Marunouchi Kitaguchi Building,
1-6-5, Marunouchi, Chiyoda-ku, Tokyo 100-8260
Japan
TEL: +81-3-6266-6400
March 30, 2006
Flight Test Results for Scramjet Engine (Follow-up Report)
The Japan Aerospace Exploration Agency (JAXA) performed a scramjet
engine flight test * using the HyShot flight experiment system at
the Woomera range in Australia at 11:40 a.m. on March 30, 2006
(Japan Standard Time, JST [0240 UTC]) The actual flight test
operations were commissioned to the University of Queensland (UQ)
in Australia.
According to the UQ, telemetry data from the HyShot flight experiment
system was received including rocket flight data and scramjet engine
test data.
The data will be analyzed to confirm the rocket flight trajectory
today. It will take a few more days to find out the test results, and
we will inform you of the results as soon as we receive them.
- For more details about the scramjet engine test, please refer
to the press release on March 20, 2006,
http://www.jaxa.jp/press/2006/03/20060320_ramjet_e.html
Public Affairs Department
Japan Aerospace Exploration Agency (JAXA)
Marunouchi Kitaguchi Building,
1-6-5, Marunouchi, Chiyoda-ku, Tokyo 100-8260
Japan
TEL: +81-3-6266-6400
March 30, 2006
Flight Test Results for Scramjet Engine (Follow-up Report #2)
The Japan Aerospace Exploration Agency (JAXA) would like to provide
more information about our scramjet engine flight test that used the
HyShot flight experiment system at the Woomera range in Australia at
11:40 a.m. on March 30, 2006 (Japan Standard Time, JST [0240 UTC]).
The actual flight test operations were commissioned to the University of
Queensland (UQ) in Australia.
The UQ informed JAXA that the highest altitude reached by the rocket
was about 290 km, which is approximately 10% lower than the scheduled
320 km, according to the telemetry data sent from the HyShot.
We will continue to analyze the telemetry data to find out the impact
of the deviated rocket flight on the scramjet engine. We will inform
you of the results as soon as we receive them.
Reference press releases
- Commissioned Flight Test for Scramjet Engine (March 20, 2006)
http://www.jaxa.jp/press/2006/03/20060320_ramjet_e.html - Flight Test Results for Scramjet Engine (March 30, 2006)
http://www.jaxa.jp/press/2006/03/20060330_ramjet_e.html - Flight Test Results for Scramjet Engine (Follow-up Report) (March 30,