Heat shield

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A heat shield is designed to shield a substance from absorbing excessive heat from an outside source by either dissipating, reflecting or simply absorbing the heat. It is often used as a form of Exhaust Heat Management.

Uses[edit]

Automotive[edit]

Due to the large amounts of heat given off by internal combustion engines, heat shields are used on most engines to protect components and bodywork from heat damage. As well as protection, effective heat shields can give a performance benefit by reducing the under-bonnet temperatures, therefore reducing the intake temperature. Heat shields vary widely in price, but most are easy to fit, usually by stainless steel clips or high temperature tape. There are two main types of automotive heat shield:

  • The Rigid heat shield has, until recently, been made from solid steel, but is now often made from aluminum. Some high-end rigid heat shields are made out of aluminum sheet or other composites, with a ceramic thermal barrier coating to improve the heat insulation.
  • The Flexible heat shield is normally made from thin aluminum sheeting, sold either flat or in a roll, and is bent by hand, by the fitter. High performance flexible heat shields sometimes include extras, such as ceramic insulation applied via plasma spraying. These latest products are commonplace in top-end motorsports such as Formula 1.
  • Textile heat shields used for various components such as the exhaust, turbo, DPF, or other exhaust component.

As a result, a heat shield is often fitted by both amateur and professional personnel during a phase of engine tuning.

Space[edit]

Apollo 12 capsule's ablative heat shield (after use) on display at the Virginia Air and Space Center
Thermal soak aerodynamic heat shield used on the Space Shuttle.

Spacecraft which land on a body with an atmosphere, such as Earth, Mars and Venus, currently do so by entering at high speeds, depending on friction rather than rocket power to slow the craft. A side effect of this is aerodynamic heating, which in the case of an Earth (or Venus) reentry can be destructive. An aerodynamic heat shield consists of a protective layer of special materials to dissipate the heat. Two basic types of aerodynamic heat shield have been used:

Some spacecraft also use a heat shield (in the conventional automotive sense) to protect fuel tanks and equipment from heat produced by a large rocket engine. Such shields were used on the Apollo Service Module and Lunar Module descent stage.

Industry[edit]

Heat shields are often used to protect heat-sensitive components used in various industrial processes.

Firearms[edit]

Main article: Barrel shroud

Heat shields are often affixed to semi-automatic or automatic rifles and shotguns in order to protect the user's hands from the heat caused by firing shots in rapid succession. They have also often been affixed to pump-action combat shotguns, allowing the soldier to grasp the barrel while using a bayonet.

See also[edit]

References[edit]