Résumé:
This paper examines the effectiveness of using a pulsating cross-flowfluid jet for
thermal enhancement in a microchannel. The proposed technique uses a novel flow
pulsing mechanism termed (synthetic jet) that injects into the microchannel a highfrequency
fluid jet with a zero-net-mass flow through the jetorifice. The
microchannelflow interacted by the pulsed jet is modeled as a two-dimensional
finitevolume simulation with unsteady Reynolds-averaged Navier–Stokes equations
while using the ShearStress-Transport (SST) k–u turbulence model to account for fluid
turbulence. For a range of conditions,the special characteristics of this periodically
interrupted flow are identified while predicting the associated convective heat transfer
rates. Results indicate that the pulsating jet leads to outstanding thermalperformance in
the microchannel increasing its heat dissipation by about 4.3 times compared toa
channel without jet interaction within the tested parametric range. The degree of
enhancement is firstseen to grow gently and then rather rapidly beyond a certain flow
condition to reach a steady value. Theproposed strategy has the unique intrinsic ability
to generate outstanding degree of thermal enhancement in a microchannel without
increasing its flow pressure drop. The technique is envisaged to haveapplication potential in miniature electronic devices where localised cooling is desired over a base
heatdissipation load.
