Diverterless supersonic inlet
Encyclopedia
A diverterless supersonic inlet (DSI) is a type of jet engine
air intake used by some modern combat aircraft to control air flow into their engines. It consists of a "bump" and a forward-swept inlet cowl, which work together to divert boundary layer
airflow away from the aircraft's engine while compressing the air to slow it down from supersonic speed. The DSI can be used to replace conventional methods of controlling supersonic and boundary layer airflow, such as the intake ramp
and inlet cone
, which are more complex, heavy and expensive.
Research into the DSI was done by Lockheed Martin
in the early 1990s. The first DSI was flown on 11 December 1996, installed on a F-16 Block 30 fighter and replacing aircraft's original intake diverter. The modified F-16 demonstrated a maximum speed of Mach 2.0 and handling characteristics similar to a normal F-16. It was also shown that subsonic specific excess power was slightly improved. A DSI was later incorporated into the design of the Lockheed Martin F-35 Lightning II.
The JF-17 Thunder
also uses a DSI. Work on the DSI was started in 1999 with the aim of improving aircraft performance and took almost two years, during which a number of models underwent wind tunnel tests at different speed regimes. It was found that the DSI gave high performance, high total pressure recovery, low integrated distortion and good engine/intake matching.
The Lockheed Martin F-35 Lightning II, JF-17 Thunder
, Chengdu J-10B
and Chengdu J-20
fighters all incorporate DSI.
Jet engine
A jet engine is a reaction engine that discharges a fast moving jet to generate thrust by jet propulsion and in accordance with Newton's laws of motion. This broad definition of jet engines includes turbojets, turbofans, rockets, ramjets, pulse jets...
air intake used by some modern combat aircraft to control air flow into their engines. It consists of a "bump" and a forward-swept inlet cowl, which work together to divert boundary layer
Boundary layer
In physics and fluid mechanics, a boundary layer is that layer of fluid in the immediate vicinity of a bounding surface where effects of viscosity of the fluid are considered in detail. In the Earth's atmosphere, the planetary boundary layer is the air layer near the ground affected by diurnal...
airflow away from the aircraft's engine while compressing the air to slow it down from supersonic speed. The DSI can be used to replace conventional methods of controlling supersonic and boundary layer airflow, such as the intake ramp
Intake ramp
An intake ramp is a rectangular, plate-like device within the air intake of a jet engine, designed to generate a shock wave to aid the inlet compression process at supersonic speeds. The ramp sits at an acute angle to deflect the intake air from the longitudinal direction...
and inlet cone
Inlet cone
Inlet cones are a component of some supersonic aircraft. They are primarily used on ramjets, such as the turboramjets of the SR-71 or the pure ramjets of the D-21 Tagboard and Lockheed X-7...
, which are more complex, heavy and expensive.
Research into the DSI was done by Lockheed Martin
Lockheed Martin
Lockheed Martin is an American global aerospace, defense, security, and advanced technology company with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta in March 1995. It is headquartered in Bethesda, Maryland, in the Washington Metropolitan Area....
in the early 1990s. The first DSI was flown on 11 December 1996, installed on a F-16 Block 30 fighter and replacing aircraft's original intake diverter. The modified F-16 demonstrated a maximum speed of Mach 2.0 and handling characteristics similar to a normal F-16. It was also shown that subsonic specific excess power was slightly improved. A DSI was later incorporated into the design of the Lockheed Martin F-35 Lightning II.
The JF-17 Thunder
JF-17 Thunder
The PAC JF-17 Thunder , or CAC FC-1 Xiaolong , is a light-weight, single-engine, multi-role combat aircraft developed jointly by the Chengdu Aircraft Industries Corporation of China, the Pakistan Air Force and the Pakistan Aeronautical Complex...
also uses a DSI. Work on the DSI was started in 1999 with the aim of improving aircraft performance and took almost two years, during which a number of models underwent wind tunnel tests at different speed regimes. It was found that the DSI gave high performance, high total pressure recovery, low integrated distortion and good engine/intake matching.
The Lockheed Martin F-35 Lightning II, JF-17 Thunder
JF-17 Thunder
The PAC JF-17 Thunder , or CAC FC-1 Xiaolong , is a light-weight, single-engine, multi-role combat aircraft developed jointly by the Chengdu Aircraft Industries Corporation of China, the Pakistan Air Force and the Pakistan Aeronautical Complex...
, Chengdu J-10B
Chengdu J-10
The Chengdu J-10 is a multirole fighter aircraft designed and produced by the People's Republic of China's Chengdu Aircraft Industry Corporation for the People's Liberation Army Air Force...
and Chengdu J-20
Chengdu J-20
The Chengdu J-20 is a purported fifth-generation, stealth, twin-engine fighter aircraft prototype developed by Chengdu Aircraft Industry Group for the Chinese People's Liberation Army Air Force . In late 2010, the J-20 underwent high speed taxiing tests. The J-20 made its first flight on 11...
fighters all incorporate DSI.
See also
- Chengdu J-10Chengdu J-10The Chengdu J-10 is a multirole fighter aircraft designed and produced by the People's Republic of China's Chengdu Aircraft Industry Corporation for the People's Liberation Army Air Force...
- Chengdu J-20Chengdu J-20The Chengdu J-20 is a purported fifth-generation, stealth, twin-engine fighter aircraft prototype developed by Chengdu Aircraft Industry Group for the Chinese People's Liberation Army Air Force . In late 2010, the J-20 underwent high speed taxiing tests. The J-20 made its first flight on 11...
- JF-17 ThunderJF-17 ThunderThe PAC JF-17 Thunder , or CAC FC-1 Xiaolong , is a light-weight, single-engine, multi-role combat aircraft developed jointly by the Chengdu Aircraft Industries Corporation of China, the Pakistan Air Force and the Pakistan Aeronautical Complex...
- Lockheed Martin F-35 Lightning II