Temperature Prediction for High Pressure High Temperature Condensate Gas Flow Through Chokes

• Main Authors: Changjun Li, Wenlong Jia, Xia Wu
• Format: Article
• Language: English
• Published: MDPI AG 2012-03-01
• Series: Energies
• Subjects: high pressure and high temperature; condensate gas; choke; temperature prediction; model
• Online Access: http://www.mdpi.com/1996-1073/5/3/670/

This study developed a theoretical model for predicting the downstream temperatures of high pressure high temperature condensate gas flowing through chokes. The model is composed of three parts: the iso-enthalpy choke model derived from continuity equation and energy conservation equation; the liquid-vapor equilibrium model based on the SRK equation of state (EoS); and the enthalpy model based on the Lee-Kesler EoS. Pseudocritical properties of mixtures, which are obtained by mixing rules, are very important in the enthalpy model, so the Lee-Kesler, Plocker-Knapp, Wong-Sandler and Prausnitz-Gunn mixing rules were all researched, and the combination mixing rules with satisfactory accuracy for high pressure high temperature condensate gases were proposed. The temperature prediction model is valid for both the critical and subcritical flows through different kinds of choke valves. The applications show the model is reliable for predicting the downstream temperatures of condensate gases with upstream pressures up to 85.54 MPa and temperatures up to 93.23 °C. The average absolute errors between the measured and calculated temperatures are expected for less than 2 °C by using the model.