Compressible Flow: Energy Lecture 22 ME EN 412 Andrew Ning - PDF document

Compressible Flow: Energy Lecture 22 ME EN 412 Andrew Ning aning@byu.edu Outline Energy Equation Speed of Sound Stagnation Quantities

Energy Equation Energy Equation rate of accumulation + rate of outflow − rate of inflow = rate of production

Work Differential form

along a streamline: h 1 + V 2 2 + gz 1 + q = h 2 + V 2 1 2 2 + gz 2 Speed of Sound

Speed of Sound sound wave �� ∂p � a = ∂ρ s

Stagnation Quantities Stagnation Quantities T 0 T = 1 + γ − 1 M 2 2

� γ/ ( γ − 1) � P 0 1 + γ − 1 M 2 P = 2 � 1 / ( γ − 1) � ρ 0 1 + γ − 1 M 2 ρ = 2 Example problem with helium-filled balloon in car.