Cable thermal modeling and analysis

Computer-aided finite-element modeling (FEM) is used to develop ampacity data for electric submersible pump (ESP) cables. Computer modeling allows for a more application-specific study of the incorporation of the tubing and casing into the model. The incorporation of these factors into the model changes the nature of the heat transfer and allows for different temperatures to be modeled in the produced fluid and casing. The casing size plays a larger role in calculating conductor temperature than does tubing size. Changes in the tubing temperature prove to be more important than changes in the casing temperature. The use of 2 7/8" tubing, 7" casing, and a constant 25°F temperature differential between the production fluid and the casing provide ampacity data which correlate very well with published IEEE and API data for the cable studied: a #4 AWG EPDM-insulated round cable