Parameter study for oil spray cooling on endwindings of electric machines via Eulerian–Lagrangian simulationShow others and affiliations
2023 (English)In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 235, article id 121281Article in journal (Refereed) Published
Abstract [en]
The demand for larger power density and torque for the power traction motors used in electrified transportation puts forward a requirement for better thermal management methods. Spray cooling is a promising direct liquid cooling technique that has been proved to possess high heat removal capability in previous research. This paper investigates the heat transfer characteristics of spray cooling on endwindings of electric machines via numerical simulation through an Eulerian–Lagrangian approach. The utilized numerical models and calculated results are validated with experimentally measured data. The influence of different parameters and options involved in the simulation settings on the final results, like the stream numbers for the spray injector, the constant heat flux versus constant temperature thermal boundary condition, the influence of splashing, the effect of heat conduction in the endwindings and the Saffman lift force, only solving the energy equation for the air after its flow field reaches a steady-state, are evaluated. Parameter analyses are also conducted for operation conditions, configuration of the spray nozzles, and material properties of the coolant liquid. It is found that larger flow rate, smaller droplet size, lower spray height, more nozzle numbers, larger thermal conductivity and smaller viscosity of the coolant liquid tend to increase the overall heat transfer performance.
Place, publisher, year, edition, pages
Elsevier BV , 2023. Vol. 235, article id 121281
Keywords [en]
CFD simulation, DPM, Electric machines, Endwindings, Multi-nozzles, Spray cooling
National Category
Energy Engineering Fluid Mechanics
Identifiers
URN: urn:nbn:se:kth:diva-334938DOI: 10.1016/j.applthermaleng.2023.121281ISI: 001064994300001Scopus ID: 2-s2.0-85168519580OAI: oai:DiVA.org:kth-334938DiVA, id: diva2:1792904
Note
QC 20230830
2023-08-302023-08-302025-02-09Bibliographically approved