Flow patterns and heat transfer mechanisms during flow boiling over open microchannels in tapered manifold (OMM)

Thermal Management of High-Power Density Electric Motors for Electrification of Aviation and Beyond

“…Manifold-microchannels (MMC), the area enhancement geometry of interest in this dissertation for high heat flux two-phase cooling, were used by Baummer et al [64] to achieve a base heat flux of 300 W/cm 2 with HFE-7100 as the working fluid. A later generation of the design achieved 1230 W/cm 2 with the low-pressure refrigerant R245fa as the working fluid [52].…”

A hierarchical manifold microchannel heat sink array for high-heat-flux two-phase cooling of electronics

“…A variety of heat sink designs have been employed to dissipate larger heat fluxes by delaying CHF or reducing the pressure drop in two-phase operation compared to a conventional design with straight, parallel channels fed by a single header. These designs have implemented one or more of features such as vapor venting [10], pin-fins and interrupted channels of various shapes and configurations [10][11][12], wick structures to aid in thin film evaporation [13][14][15], microchannels with reentrant cavities and/or inlet restrictors [16], microgaps [17], arrays of jets [18][19][20][21], diverging channels [22,23], microchannels fed with tapered manifolds [24], and stacked heat sinks [25]. Heat fluxes as high as 1127 W/cm² have been dissipated with dielectric fluids [26] using a 10 mm × 20 mm copper heat sink that incorporated both flow boiling in microchannels and jet impingement.…”