Steady-state hydraulic thermodynamic calculation algorithm in long gas-condensate pipeline

Hydraulic thermodynamic calculation algorithm in steady-state is presented in this paper for long gas-condensate pipeline based on the principle of multiphase flow and chemical engineering thermodynamics.Simplified energy equation is applied to couple hydraulic and thermodynamic calculation.Pressure temperature and hold-up of each section is confirmed with iterative way.In algorithm,Barnea method is adapted to predicting flow-pattern in any physical property,dip angle and diameter.Adiabatic flash is introduced to evaluate gas-liquid composition in local pressure and temperature.Friction hold-up and velocity is calculated by mechanical model of each flow-pattern.The calculation on actual gas-condensate pipelines is conducted and the results are compared averaged real-time data gathering in field.It turns out that the solution is stable and close to field data,satisfying large pipeline engineering demand in computing accuracy.