CFD analysis of a real gas flowing through a choke valve - flow behaviour and Joule Thomson effect

Mesh external seawater domain

Contours of internal fluid Mach number and temperature

PDL Engineering Group has a wealth of experience in  delivering engineering solutions for valve and actuator clients. Their team of dedicated analysis experts have worked on many interesting and complex projects to solve the most challenging engineering problems.

They recently performed extensive CFD analysis work to assess the steady-state compressible flow behaviour and the associated Joule Thomson cooling effect of a real gas flowing through a choke valve.

The team used ANSYS CFX, ANSYS DesignModeler and ANSYS Meshing tools to simulate a model for a specified inlet and outlet pressure; the choke set point position and the geometry including the valve body, internal fluid and external seawater domains, with heat transfer modelled between each domain.

The main objective of the project was to assess the temperature at the inlet and outlet of the valve body and the distribution of internal fluid flow rate and variables including velocity, pressure, Mach number and Turbulent KE.

The fluid properties were calculated using the GERG 2004 equation of state model, from flow conditions provided by the customer. This determined the flow of hydrocarbon gas through the valve with associated heat transfer between the internal fluid, solid valve and external seawater domain.

The GERG simulations were found to be non-convergent at low temperatures, required to determine the full rupture conditions. Hence the Peng-Robinson equation of state model was used to achieve a solution, using real gas mixing roles based on the Van der Waals formulation.

All of the analysis work was developed in accordance with BS EN ISO 9001:2008.

To find out more about the PDL team’s proven track record with clients who rely on them to validate, understand, test and optimise their valves and actuators visit their website which showcases their expertise and experience at www.pdl-group.com.

Tel No:     + 44 (0) 1 434 609 473
Email:      solutions@pdl-group.com
Website:  www.pdl-group.com

Published: 3rd November 2022