Some Generalizations in One-Dimensional Constant Density Fluid Dynamics

Abstract

We present a Generalized Constant Density Flow Function, Γ , which is shown to have direct application in the treatment of many simplified, workless, one-dimensional flow processes. Those particular flow processes treated in this paper are: the familiar adiabatic flows, with or without friction, with area variations always allowed; and diabatic flows with or without friction, with area variations always allowed. Moreover, the Γ function is shown to have significance in a generalized flow process having an arbitrary combination of heat transfer, friction, and area and elevation variation. Development of the Γ function is given in some detail. Schematic isentropic, Fanno, Rayleigh, and isothermal flow maps are presented in terms of the conventional enthalpy—entropy diagram, and again in terms of the pressure ratio—Γ diagram. Numerical examples are included to illustrate the solution of typical problems through use of the Generalized Constant Density Flow Function.