High performance cooling of a HVDC converter using a fatty acid ester‐based phase change dispersion in a heat sink with double‐layer oblique‐crossed ribs

Research output: Contribution to journalArticlepeer-review


  • Ludger Fischer
  • Geng Qiao
  • Ernesto Mura

Colleges, School and Institutes

External organisations

  • Lucerne University of Applied Sciences and Arts Horw Switzerland


The paper concerns with a high performance cooling method for a HVDC converter using fatty acid ester‐based phase change dispersion (PCD) in a heat sink with double‐layer oblique‐crossed ribs. Thermo‐physical properties of PCDs were first characterized under both solid and liquid states, and the cooling performance of the heat exchanger was then experimentally examined, by heating two copper blocks clamped closely to the aluminium heating surfaces. A three‐dimensional Euler‐Euler multiphase approach was further performed to evaluate the thermal performance under different operating conditions including heating power, flowrate and PCD concentration. The results showed that the viscosity of PCD can be a 100 times that of water, but the increased pumping power was only ~17.01% on average. The use of the PCD achieved a lower temperature of heat sink and fluid than that of water under the same set of conditions due to the latent heat of the PCM, thus enabling a safer and cooler environment for temperature‐sensitive HVDC components such as insulated gate bipolar transistors (IGBT). An optimal set of working conditions was proposed and a flowrate of 8 L/min under a heating power of 1.1 kW and a PCM concentration of 25% was recommended for industrial cooling operations.


Original languageEnglish
Pages (from-to)5819-5840
JournalInternational Journal of Energy Research
Issue number7
Early online date26 Mar 2020
Publication statusPublished - 10 Jun 2020


  • Euler‐Euler multiphase modelling, fatty acid ester, HVDC converter cooling, multi‐stream heat sink, oblique‐crossed ribs, phase change dispersion