ISSN Online: 2379-1748
ISBN Flash Drive: 978-1-56700-469-4
ISBN Online: 978-1-56700-470-0
Second Thermal and Fluids Engineering Conference
Experimental Study on the Pool and Flow Boiling Heat Transfer Enhancement for Silicon Chips with Microstructured Surfaces
Abstract
An experimental study of pool boiling heat transfer was conducted for micro-pin-finned surfaces. The micro-pinfinned
surfaces had different pitches, configurations and shapes. The experimental condition covered three
different liquid subcoolings (15K, 25K, 35K), and dielectric liquid FC-72 was used as working fluid. Fin pitch
was found to have significant effects on the boiling heat transfer coefficient and critical heat flux, but the
influence was not monotonous. Surface with removed micro-pin-fins showed higher HTC and CHF than aligned
micro-pin-fins, which was owing to the enhancement of capillary flow performance. Compared with square
micro-pin-fins, circular micro-pin-fins demonstrated excellent heat transfer performance under the same surface
area, and the critical heat flux was increased by 13%. Besides, heat transfer performance of flow boiling over
micro-pin-finned surfaces was investigated under the conditions of liquid subcooling of 35K and three different
liquid velocities (0.5m/s, 1 m/s, 2 m/s). Three pitches (45μm, 60μm, 75μm) were chosen for staggered square
micro-pin-fins of 30μm×60μm (named S-SPF30-60-45, S-SPF30-60-60, S-SPF30-60-75). The effects of pin
pitch, configuration and shape on flow boiling heat transfer were also explored. In single-phase region, the slope
of boiling curve increased with the pin pitch increasing. The critical heat flux of S-SPF30-60-60 and S-SPF30-
60-75 were comparative, whereas the S-SPF30-60-45 showed the lowest CHF.