الفهرس 
Introduction and Literature ReviewOnly 14 pages are availabe for public view
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Abstract
A numerical and experimental study is made on a laminar slot and circular jet to study the effect of jet Reynolds number, jet to plate spacing, jet to jet spacing on the convective heat and mass transfer. Also, the effect of jets Reynolds number ratio and cross flow on the performance of slot jet are studied. Numerical study is made for sex cases: confined circular laminar jet impinging into flat plate, two confined opposed laminar circular jets impinging into each other, confined laminar slot jet impinging into flat plate, two confined opposed laminar slot jets impinging into each other, confined laminar slot jet impinging into flat plate in the presence of cross flow and two confined opposed laminar slot jets impinging into each other in the presence of cross flow. Jet fluid with uniform exit velocity, temperature and concentration mixes with quiescent ambient and forms single phase flow jet. Hydrodynamics of the flow field and mixing index are presented. Effect of jet Reynolds number (50 to 500), jet to plate distance (2 to 5 jet width) is studied and denotes that local and average Nusselt and Sherwood numbers increases with increasing jet Reynolds number. Also, local and average Nusselt and Sherwood numbers increases with decreasing jet to plate spacing at various jet Reynolds numbers. The effect of jet Reynolds number ratio is studied and denotes that local and average Nusselt and Sherwood numbers decreases with increasing jet Reynolds number ratio at the strongest jet plate but increases at the other plate. Also mixing index increases with increasing Reynolds number and with increasing jet to jet spacing. Effect of cross flow with the slot jet is studied with velocity ratio (cross flow to jet flow) ranges (0.1 – 2.0). The results shows that the average Nusselt and Sherwood numbers decreases with increasing velocity ratio up to (0.8 in case of confined impinging slot jet) and (1.0 in case of two confined opposed impinging slot jets) )and then increases due to that the effect of cross flow on the plate is higher than the effect of jet flow. Experimental study is made under conditions of Saturated steam at atmospheric pressure and 100 ºC is used as a working fluid issuing from slot jets of width 2 mm. where, air at atmospheric pressure and about 30 ºC and 60% relative humidity is used as the cross flow working fluid in case of cross flow. The study is made for four cases: impinging confined laminar slot jet (2 mm in width and 10 mm in length) on a flat plate at constant temperature, two opposed impinging confined laminar slot jet (2 mm in width and 10 mm in length), impinging confined laminar slot jet on a flat plate at constant temperature with cross flow and two opposed impinging confined laminar slot jet with cross flow . An experimental test rig is designed and constructed to be suitable for the studied cases. Dry bulb temperatures, relative humidity, local and average Nusselt and Sherwood numbers are presented. Effect of jet Reynolds number in the rage of (50-500) and cross flow ratio (0.25-2.0) are studied and denotes that, local and average Nusselt and Sherwood numbers increase with increasing jet Reynolds number. On the other hand, local and average Nusselt and Sherwood numbers decrease with increasing cross flow ratio. Also, local and average Nusselt and Sherwood numbers in the case of two opposed jets are less than in the case of impinging jet.