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Basics of GAS DYNAMICS . P M V Subbarao Associate Professor Mechanical Engineering Department I I T Delhi. Alphabets of this new literature called Gas Dynamics . Role of Sonic Velocity in Engineering. c. c. High pressure and High temperature fluid in closed tank. .
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Basics of GAS DYNAMICS P M V Subbarao Associate Professor Mechanical Engineering Department I I T Delhi Alphabets of this new literature called Gas Dynamics
Role of Sonic Velocity in Engineering c c High pressure and High temperature fluid in closed tank. Stagnation Conditions.
c+w c-w c w w Role of Sonic Velocity in Engineering Velocity of sound at any give flow velocity w.
c+c c-c w w Role of Sonic Velocity in Engineering Define this critical parameter Velocity of sound, c Velocity of sound when flow velocity w=c.
Choking of Nozzle Extent of Valve Opening
Moving Disturbance In A Fluid • As an object moves through a fluid medium it creates pressure waves. • Pressure waves travel out at the speed of sound which in term depends on gas properties and temperature (more on this later). • If the object is traveling significantly slower than sonic velocity, then pressure waves travel out uniformly similar to waves on the surface of a pond.
Moving Disturbance In A Fluid • As the object approaches the speed of sound, it begins to catch up with the pressure waves and creates an infinitesimally weak flow discontinuity just ahead of the aircraft
Moving Disturbance In A Fluid • As the vehicle breaks the speed of sound, the infinitesimally weak Shock waves begin to add up along a “Mach Line” and form a strong pressure wave with highly compressed air, called a shockwave.
Moving Disturbance In A Fluid • As Mach number increases, the strength of the shock wave increases and the Angle of the shockwave becomes increasingly severe • Mach Angle Credit: Selkirk College Professional Aviation Program