Fluid transients in pipes. Estimation of maximum pressures and forces in steam lines
Abstract
Available as part of the ESDU Subseries on Fluid Mechanics (Internal Flow), this document gives a graphical method for estimating the timedependent pressure changes and piping forces that follow from a rapid value closure in a onepipe system of constant crosssection carrying superheated steam. The method also assumes a frictionless flow and ignores wave steepening effects. A computer program listing in FORTRAN is also included that applies to any gas that obeys the perfect gas law, and takes into account the effects of both wall friction and wave steepening. In that case sections of the pipeline can have different crosssectional areas and that can be used to treat a pipeline with branched ends. Worked examples are included for both methods and in the case of the computer program show specimen printout of the input data, and of the output which includes the time variation of pressure, velocity and density at three points in the pipeline chosen by the user together with values of maximum and minimum pressure at 25 points (a value that is also open to choice by the user). The example is run for a valve with a linear variation of area with time, and for one with a nonlinear characteristic.
 Publication:

NASA STI/Recon Technical Report N
 Pub Date:
 September 1986
 Bibcode:
 1986STIN...8712805.
 Keywords:

 Applications Programs (Computers);
 Flow Characteristics;
 Fluid Pressure;
 Pipe Flow;
 Pressure Oscillations;
 Steam Flow;
 Surges;
 Flow Velocity;
 Fortran;
 Linear Systems;
 Nonlinear Systems;
 Time Dependence;
 Valves;
 Fluid Mechanics and Heat Transfer