TY - JOUR
T1 - A novel cooling geometry for subsea variable speed drives
AU - Militão, Lucas A.
AU - Fernandes, Caio D.
AU - dos Santos, Diego
AU - Machado, Douglas M.
AU - Heldwein, Marcelo L.
AU - Rambo, Carlos R.
AU - da Silva, Alexandre K.
AU - Barbosa, Jader R.
N1 - Publisher Copyright:
© 2020 Elsevier Ltd
PY - 2021/2/25
Y1 - 2021/2/25
N2 - Experimental and theoretical analyses are conducted to evaluate the passive cooling performance of a novel geometry for subsea variable speed drives, a common piece of equipment in deep-sea oil exploration. Relying on the sea water as a low-temperature thermal reservoir, the new design forms an enclosed, annular space with centrally located modular boards that compose the power electronics inverter. Buoyancy-induced motion of a dielectric coolant conveys the heat dissipated by the electronic boards to the sea water through the outer and innermost walls of the annular enclosure. A thermal network model is implemented and used to optimize the enclosure geometry through a genetic algorithm, which served as a reference for a scaled experimental setup. A Computational Fluid Dynamics (CFD) simulation of the conjugate heat transfer yielded temperature distributions on the electronic boards and temperature and fluid velocity fields inside the enclosure. A comparison between the experimental data and the modeling results indicated a good agreement, with average RMS deviations of a modified Nusselt number of 7.0% and 8.5% for the thermal network and CFD analysis, respectively. For a 140-W operating point dissipation rate in the scaled test setup, the thermal network and the CFD models presented maximal deviations of 4°C and 2.3°C with respect to the heat sink temperature measurements.
AB - Experimental and theoretical analyses are conducted to evaluate the passive cooling performance of a novel geometry for subsea variable speed drives, a common piece of equipment in deep-sea oil exploration. Relying on the sea water as a low-temperature thermal reservoir, the new design forms an enclosed, annular space with centrally located modular boards that compose the power electronics inverter. Buoyancy-induced motion of a dielectric coolant conveys the heat dissipated by the electronic boards to the sea water through the outer and innermost walls of the annular enclosure. A thermal network model is implemented and used to optimize the enclosure geometry through a genetic algorithm, which served as a reference for a scaled experimental setup. A Computational Fluid Dynamics (CFD) simulation of the conjugate heat transfer yielded temperature distributions on the electronic boards and temperature and fluid velocity fields inside the enclosure. A comparison between the experimental data and the modeling results indicated a good agreement, with average RMS deviations of a modified Nusselt number of 7.0% and 8.5% for the thermal network and CFD analysis, respectively. For a 140-W operating point dissipation rate in the scaled test setup, the thermal network and the CFD models presented maximal deviations of 4°C and 2.3°C with respect to the heat sink temperature measurements.
KW - Computational Fluid Dynamics
KW - Deep-sea oil exploration
KW - Equivalent thermal network
KW - Frequency inverter
KW - Heat transfer augmentation
KW - Thermal management
UR - http://www.scopus.com/inward/record.url?scp=85099194450&partnerID=8YFLogxK
U2 - 10.1016/j.applthermaleng.2020.116483
DO - 10.1016/j.applthermaleng.2020.116483
M3 - Article
AN - SCOPUS:85099194450
SN - 1359-4311
VL - 185
JO - Applied Thermal Engineering
JF - Applied Thermal Engineering
M1 - 116483
ER -