Modernization of Todini Global Gradient Algorithm for hydraulic analysis of networks with choked flow

Leonid Korelstein,N.N Novitsky,C Sarica,V.A Stennikov,V.R Chupin,E Khaltar,B Serttter,V.V Tarasevich,M Negnevitsky,S.A Miedema,E Todini,L.B Korelstein,M.G Sukharev

doi:10.1051/e3sconf/202021901003

Abstract

The modification of well-known Global Gradient Algorithm for hydraulic network flow distribution problem is proposed. This modification is based on problem equations rewritten in “upstream” form and on modified form of linearization, and can be effectively used for piping networks with gas and multiphase gas-liquid flow with multiple choked flow.

Highlights

Different methods of solving hydraulic network flow distribution problem were proposed [1, 2], and Global Gradient Algorithm (GGA) was one of the most effective
Application of GGA for process piping was investigated by the author and his colleagues in a number of publications [12,13,14], and PASS/HYDROSYTEM software [15], developed by PSRE Co, uses GGA successfully for thermal and hydraulic analysis of piping networks transporting both one-phase and multiphase phase gas-liquid fluids
In its original form GGA cannot be applied to networks with choked or nearchoked flow – while analysis of such flow is an important practical problem for some types of process piping – for example pressure relieve discharge systems or multiphase gas-liquid transfer pipelines transporting oil from furnace to column

Summary

Introduction

Different methods of solving hydraulic network flow distribution problem were proposed [1, 2], and Global Gradient Algorithm (GGA) was one of the most effective. In its original form GGA cannot be applied to networks with choked or nearchoked flow – while analysis of such flow is an important practical problem for some types of process piping – for example pressure relieve discharge systems or multiphase gas-liquid transfer pipelines transporting oil from furnace to column. Such flow was investigated by the author in [16-19]. This article proposes modified form of GGA (MGGA), which (along with decomposition method) hopefully allows to solve flow distribution problem for choked flows. Further in this article we will consider on hydraulic analysis, i.e. will consider 2nd thermodynamic parameter (besides pressure) describing state of the fluid (for example temperature for isothermal flow or full enthalpy for adiabatic flow) to be fixed

GGA equations

MGGA equations