Shock wave

Shock wave

A Shock wave is a type of propagating disturbance. When a wave moves faster than the local speed of sound in a fluid, it is a shock wave. Like an ordinary wave, a shock wave carries energy and can propagate through a medium; however, it is characterized by an abrupt, nearly discontinuous change in pressure, temperature and density of the medium.

Mechanics

Shock waves differ from sound waves in that the wave front, where compression takes place, is a region of sudden and violent change in stress, temperature and density. The shock wave energy, like sound energy, is imparted to the medium through particle-to-particle interaction.

Formation

Shock waves form when a pressure front moves at supersonic speeds and pushes on the surrounding air. For shock wave formation, it's necessary that the wave speed exceeds the speed of sound.

Types of Shock Waves

There are several types of shock waves, such as:

• Normal shock - occurs when a shock wave forms perpendicular to the flow direction.
• Oblique shock - occurs when a shock wave forms at an angle to the flow direction.
• Bow shock - occurs when a shock wave forms in front of a body moving through a fluid at a speed greater than the speed of sound in the fluid.
• Detonation wave - a type of shock wave that occurs in explosive materials.

Applications

Shock waves are used in various fields, including:

• Medicine - in the treatment of certain medical conditions, such as kidney stones and certain cardiac conditions.
• Aerospace engineering - in the design of aircraft and spacecraft.
• Astrophysics - in the study of phenomena such as supernovae and the behavior of gases in space.

See also

• Sonic boom
• Explosion
• Supersonic speed