IDEAS home Printed from https://ideas.repec.org/a/eee/energy/v320y2025ics0360544225008977.html
   My bibliography  Save this article

Deep learning-based prediction of oil reversal in R290 heat pump systems

Author

Listed:
  • Jeong, Gil
  • Lee, Je Hyung
  • Choi, Hyung Won
  • Park, Hee Woong
  • Kim, Hyun Jong
  • Seo, Beom Soo
  • Chin, Simon
  • Kang, Yong Tae

Abstract

Recently, the R290 refrigerant has attracted significant attention due to its low global warming potential (GWP) and excellent thermal performance. To evaluate the reliability of R290 heat pump systems influenced by oil behavior of Polyalkylene glycol (PAG), this study introduces a novel oil reversal index (ORI). This index is defined as the ratio of the oil film thickness at the top and bottom of vertical pipes, providing a method to determine the occurrence and intensity of oil reversal. ORI is a metric that is not only easy to measure but also capable of accounting for the effects of oil viscosity and refrigerant solubility. It was experimentally measured under both transient and steady-state conditions, influencing factors were analyzed, and it was subsequently modeled using deep learning. The long short-term memory model with batch normalization (LSTM + BN) achieved a mean absolute percentage error (MAPE) of 12.64 % in predicting oil film thickness under transient conditions. Furthermore, by selecting top 10 most impactful parameters through feature importance analysis and retraining the model, this error was reduced to 8.81 %. Additionally, the model predicted ORI under steady-state conditions with an error of 2.21 % using 20 input features.

Suggested Citation

  • Jeong, Gil & Lee, Je Hyung & Choi, Hyung Won & Park, Hee Woong & Kim, Hyun Jong & Seo, Beom Soo & Chin, Simon & Kang, Yong Tae, 2025. "Deep learning-based prediction of oil reversal in R290 heat pump systems," Energy, Elsevier, vol. 320(C).
  • Handle: RePEc:eee:energy:v:320:y:2025:i:c:s0360544225008977
    DOI: 10.1016/j.energy.2025.135255
    as

    Download full text from publisher

    File URL: http://www.sciencedirect.com/science/article/pii/S0360544225008977
    Download Restriction: Full text for ScienceDirect subscribers only

    File URL: https://libkey.io/10.1016/j.energy.2025.135255?utm_source=ideas
    LibKey link: if access is restricted and if your library uses this service, LibKey will redirect you to where you can use your library subscription to access this item
    ---><---

    As the access to this document is restricted, you may want to search for a different version of it.

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:eee:energy:v:320:y:2025:i:c:s0360544225008977. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no bibliographic references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: Catherine Liu (email available below). General contact details of provider: http://www.journals.elsevier.com/energy .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.