Definition of a*:a*的定义 75节最后一段: As a corollary to the above considerations,we need another defined temperature, denoted by T", and defined as follows. Consider a point in a subsonic flow where the local static temperature is T. At this point, imagine that the fluid element is speeded up to sonic velocity, adiabatically. The Temperature it would have at such sonic conditions is denoted as T. Similarly, consider a point in a supersonic flow, where the local static temperature is T. At this point, imagine that the fluid element is slowed down to sonic velocity, adiabatically. Again, the Temperature it would have at such sonic conditions is denoted as ta 用*号表示的变量被称为临界参数=√Rr*称为临界音速 y+1)a (8.35) 2 12 122(y-1) In equation(8.35), a and u are the speed of sound and velocity, respectively, at any point of flow, and a'*is a characteristic value associated with that same point2( 1) ( 1) * 1 2 2 2 2 − + + = −    a u a 2 * 1 * 1 2 2 2 2 2 a u a a + − + =  −  (8.35) Definition of a*: a*的定义 7.5节最后一段：As a corollary to the above considerations, we need another defined temperature, denoted by T*, and defined as follows. Consider a point in a subsonic flow where the local static temperature is T. At this point, imagine that the fluid element is speeded up to sonic velocity, adiabatically. The Temperature it would have at such sonic conditions is denoted as T*. Similarly, consider a point in a supersonic flow, where the local static temperature is T. At this point, imagine that the fluid element is slowed down to sonic velocity, adiabatically. Again, the Temperature it would have at such sonic conditions is denoted as T*. 用*号表示的变量被称为临界参数. a* = RT * 称为临界音速. In Equation (8.35), a and u are the speed of sound and velocity, respectively, at any point of flow, and a* is a characteristic value associated with that same point