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Experimental investigation is conducted to investigate the flow and heat transfer performances of jet impingement cooling inside a semi-confined smooth channel.Effects of jet Reynolds number(varied from 10 000to 45000),orifice-to-target spacing(zn=1d—4d)and jet-to-jet pitches(xn=3d—5d,yn=3d—5d)on the convective heat transfer coefficient and discharge coefficient are revealed.For a single-row jets normal impingement,the impingement heat transfer is enhanced with the increase of impingement Reynolds number or the decrease of spanwise jet-to-jet pitch.The highest local heat transfer is achieved when zn/dis 2.For the double-row jets normal impingement,the laterally-averaged Nusselt number distributions in the vicinity of the first row jets impinging stagnation do not fit well with the single-row case.The highest local heat transfer is obtained when zn/dis 1.A smaller jetto-jet pitch generally results in a lower discharge coefficient.The discharge coefficient in the double-row case is decreased relative to the single-row case at the same impingement Reynolds number.
Experimental investigation is conducted to investigate the flow and heat transfer performances of jet impingement cooling inside a semi-confined smooth channel. Effects of jet Reynolds number (varied from 10 000 to 45000), orifice-to-target spacing (zn = 1d-4d) and jet-to-jet pitches (xn = 3d-5d, yn = 3d-5d) on the convective heat transfer coefficient and discharge coefficient are revealed. For a single-row jets normal impingement, the impingement heat transfer is enhanced with the increase of impingement Reynolds number or the decrease of spanwise jet-to-jet pitch. The highest local heat transfer is achieved when zn / dis 2. For the double-row jets normal impingement, the laterally-averaged Nusselt number distributions in the vicinity of the first row jets impinging stagnation do not fit well with the single-row case. highest highest heat transfer is obtained when zn / dis 1. a smaller jetto-jet pitch generally results in a lower discharge coefficient. discharge coefficient in the double- row case is decreased relative to the single-row case at the same impingement Reynolds number.