Studi Eksperimental Pengaruh Bilangan Reynolds pada Keefektifan dan Koefisien Tekanan Penukar Panas Berkas Pipa Eliptik Susunan Berseling

Abstract

Experimental studies have been conducted on the elliptic tube bundle with a diameter equivalent to 0.75
inches and the aspect ratio (AR) = 2.Tube bundle arranged alternate with 4-3-4 configuration and pitch
lateral (SL) = 1.5 X axis major axis. Meanwhile pitch transverse (ST) varied 1.5 and 2 X minor axis. The
Testing was carried out in a subsonic wind tunnel with wind speeds of 1 m / s - 12.6 m / s resulting
Reynolds number Reb = 346-6904 and operating temperature 49 oC, 59 oC and 69 oC. Seven tubes
inserted an electric heater produces uniform heat flux 3718 W/m2 - 3751 W/m2. The results show that the
effectiveness of the heat exchanger (Q / P) varied from 3799 to 15, decreases exponentially at low
Reynolds number and tends to asymptotic at Reynolds number above 1000. Meanwhile, the value
pressure coefficient (?p/0.5?V2) with value 3.4-10 decreased continuously at low Reynolds numbers and
asymptotic at high Reynolds number. In general, a bundle with a smaller ST has greater effectiveness and
the pressure coefficient ranges is wider. Changes in operating temperature conseqwenly no effect on the
effectiveness and the pressure coefficient at high Reynolds number.