Michael Rumbaugh and Araceli Rivera Mandujano, SLB
Cody Casey and Scott Schulte, Diamondback Energy
The thermal behavior of Electrical Submersible Pump (ESP) systems deployed in unconventional wells is poorly characterized, particularly when exposed to elevated gas volume fractions and transient flow regimes. Traditional point temperature measurements provide limited spatial resolution and do not capture how gas interference influences heat distribution along pump stages, seal sections, and motors. To address this knowledge gap, an experimental R&D deployment of distributed fiber-optic temperature sensing (DTS) was performed in a gassy unconventional well to observe continuous downhole temperature profiles along the entire ESP assembly.
The DTS system was encapsulated in a stainless-steel tube and installed externally along the ESP string, from the sensor to above discharge. The acquired data showed distinct temperature changes associated with gas-entrainment regions, as well as deviations in cooling performance from values typically assumed in ESP selection and modeling.
The intent of this work is not to propose a scalable field monitoring method, but to present rare empirical insight into actual ESP thermal profiles in gassy unconventional wells. The findings can help refine operating envelope interpretation, improve cooling-related design assumptions, and enhance diagnostic understanding using existing surveillance signals.