Fabio Gori
Department of Mechanical Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy
L. Bossi
Dipartimento di Ingegneria Meccanica Universita di Roma "Tor Vergata" Via di Tor Vergata 110 - 00133 Roma
Abstrakt
The heat transfer on two cylinders in a row by a slot jet flow of air has been investigated experimentally. The slot jet has a height of S=5 mm. The cylinders diameter is D=10 mm. The first cylinder is set at a distance H/S=6 from the slot exit. The second cylinder is set a distance from the first cylinder variable from L/S=4 to L/S=8. The Reynolds number range is ReD=4000÷20000. The influence of the first cylinder on the second one is to decrease the heat transfer in a jet flow, just opposite to what observed in a uniform flow. Local Nusselt number on the two cylinders has been investigated as a function of Reynolds number, the angle from the impinging point and the different distances between the two cylinders. A closed vortex region between the cylinders appears at a distance L/S=4 and is dependent by the Reynolds number. The best configuration of the two cylinders for obtaining the maximum heat transfer is H/S=6 and L/S=4.