ANALYSIS AND SOLUTION OF NON-ISOTHERMAL FLOW IN GAS MAINLINES UNDER CERTAIN CONDITIONS.

In this paper the pressure change in inclined gas mainlines (GM) with incline h (h equals H//2 minus H//1) is analyzed, through which the gas flows non-isothermally so that the change in its temperature T is a function of the travelled distance (T equals T(x)) which results in a change in the density of the gas as a function of pressure and temperature along the GM ( rho equals rho (P, T). The mass flow q//m of the gas is constant, also the inner diameter of the pipe D//i; D//m is the mean diameter of the pipe with or without insulation. The authors look at flows with large Reynolds numbers, that is in the square area of the lambda -Re diagram. Here, the coefficient of linear losses is calculated from Shifrinson's formula because the actual flow in GM takes place either in this area or in the transition area where we use Altshul's formula. 4 Refs.