User:E.James/Bow Shock

For other uses, see Bow shock.

A blunt body model in a supersonic wind tunnel producing a bow shock.

A Bow shock is a normal shock that occurs in front of an object within a supersonic flow. Unlike an oblique shock, the bow shock is not attached to the tip of the object in the flow. Oblique shock angles are limited in formation based on the corner angle and upstream Mach number. When these limitations are exceeded, a bow shock occurs instead of the oblique shock. Therefore, bow shocks are often seen forming around blunt objects.

The bow shock significantly increases the drag in a vehicle traveling at a supersonic speed. This property was utilized in the design of the return capsules during space missions like the Apollo program, which need a high amount of drag in order to slow down during atmospheric reentry.

Ballistics

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Applications

In atmospheric reentry, a major concern is the amount of heat transfered to an aircraft as it descends. The detached bow shock produced by a blunt body significantly reduces the amount of heat that is trasfered to the vehicle itself, when compared to a sharp-nosed vehicle.

See also

• Gas dynamics
• Oblique shock
• Shock wave
• Prandtl-Meyer expansion fan
• Moving shock

References

• Hartman, Edwin P. (1970). "PART II : A NEW WORLD OF SPEED : 1946-1958". Adventures in Research: A History of Ames Research Center, 1940-1965. NASA Center History. Scientific and Technical Information Division, Office of Technology Utilization, NASA. SP-4302.