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This paper presents an experimental work. which studies the performance of a counter flow type cooling tower. The experimental results have been carried out at a test rig which designed and investigated in Misr Oil and Soap Company. It consists of 12 cooling towers from these types. Three types of film fill packing, used during experimentation, 0were made of PVC with height range 800 - 1200 mm. During the experimentation the following quantities were varied: air flow velocity in the range 10.5-17.5 m/s and water flow rate in the range of 80-150 m3/h. The variation of temperature along the height or packed was measured by means of 16 appropriate placed thermocouples. The results show that when the mass flow rate ratio decreased, the number of transfer units (NTU) were increased. Also by decreasing the inlet air wet bulb temperature, the tower range would be increased. from this study the characteristic equation is in the form:NTU 〖 (K_(a ) A_(v@ ) V)/L =0.875[ L/(G ) ]〗^(-0.12) , which can be used in designing the counter flow coo= ling towers.

The energy required for industrial drying processes consumed by a conventional dryers are essentially thrown away without the ability to recover the latent heat of water vapor in the air, significant reductions in dryer energy usage cannot be made. In an attempt to recover the latent heat of the water vapor, a closed drying cycle is proposed, which uses a nozzle as the means to recover this energy from moist-saturated air. This nozzle condensation drying cycle (NCDC) is composed of the following components: dryer, nozzle, diffuser, air water separator, heat exchanger and compressor. Analysis of this drying cycle shows that ideally this cycle requires lower energy compared with an ideal open cycle heated dryer or a heat pump dehumidification cycle. However, which equipment isentropic efficiencies are included, the energy costs are approximately a third of the cost of the ideal open cycle healed dryer. The cycle can be operated at varying conditions, allowing for a single design to be utilized for various ap plications. Other advantages are in applications that require drying of hazardous liquids from a product.