Numerical investigation of heat transfer and pressure drop of in-line array of heated obstacles cooled by jet impingement in cross-flow

Abstract A computational study of cooling in-line array of heated obstacles simulating electronic components by jet impingement in cross-flow (JICF) has been investigated using RNG k - e turbulence model. The jet position has been changed to impinge each obstacle consecutively at different jet-to-channel Reynolds number ratios, Re j / Re c  = 1, 2, and 4. The main flow structure, the static pressure, local and average Nusselt numbers as well as the thermal enhancement factor have been investigated. The results show that there is a significant variation between the flow structures around an obstacle when subjected to JICF or CF. The friction factor for JICF is greater than that for cross-flow only (CF) by 88% at the first jet position and Re j / Re c  = 4. The irregular distribution of local Nusselt number ( Nu ) on the impinged obstacle is moderated by increasing the Reynolds number ratios. Increasing Reynolds number ratio increases the average Nusselt number ( Nu ‾ ) of the downstream obstacles and decreases it for the upstream obstacles. The increment of Nu ‾ for whole array for JICF than CF is about 26% at JP3 and Re j / Re c  = 4. Moreover, the highest value of thermal enhancement factor is attained at JP3 and it equals 12% for Re j / Re c  = 4.