Dj. Timoney et Pj. Foley, SOME EFFECTS OF AIR-FLOW MALDISTRIBUTION ON PERFORMANCE OF A COMPACT EVAPORATOR WITH R134A, Heat recovery systems & CHP, 14(5), 1994, pp. 517-523
Citations number
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Categorie Soggetti
Energy & Fuels","Engineering, Mechanical",Mechanics,Thermodynamics
An experimental facility has been constructed to enable the effects of
air flow non-uniformity on the transfer performance of refrigerant ev
aporators to be investigated. This is based on an open-circuit wind tu
nnel, which is equipped with a single component traversing LDA system,
capable of determining local mean velocities and turbulence levels. T
he refrigerant circuit uses R134a and has been designed to allow maxim
um flexibility in setting test conditions. Preliminary results are pre
sented from tests on a single circuit finned-tube evaporator with 33 t
ubes, 300 mm long, arranged in an in-line matrix 4 rows deep, with 25
mm spacing. The height of the fin block was 225 mm, the fin spacing an
d tube external diameter were 4 mm and 9.5 mm respectively. Contrary t
o expectations, increases in heat transfer duty and overall heat trans
fer coefficients were recorded as air how non-uniformities were artifi
cially introduced, whilst a constant mean air velocity was maintained.