Effect of taper on pressure recovery during flow boiling in open microchannels with manifold using homogeneous flow model

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

“…6. Taper helps in reducing the pressure drop due to increasing flow area in the flow direction as postulated by Kalani and Kandlikar [26]. The taper also helps in improving the overall stability.…”

“…By providing a tapered manifold gap above the microchannels, bubbles have room to grow away from the microchannels into the manifold and depart from the microchannel region without any resistance. The taper introduces a pressure recovery term and encourages the bubble to flow in the downstream direction due to a lower flow resistance as compared to the upstream direction [26]. This avoids flow instabilities due to flow reversal [9].…”

“…The extra flow cross-sectional area available in the flow direction due to taper allows bubbles to expand while leaving the channels filled with oncoming liquid. The pressure recovery induced by the area enlargement has been identified by Kalani and Kandlikar [26] as a major factor in reducing the overall pressure drop and improving the flow stability. This mechanism also helps in extending CHF due to stable operation.…”