Experimental Study of Forced Draft Cross Flow Wet Cooling Tower Using Splash Type Fill (original) (raw)
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This paper presents an experimental analysis of heat transfer using different shaped fills in a counter flow induced draft cooling tower. The main objective is to determine and compare the characteristics of the cooling tower using newly shaped (splash and film) fills and the regular used fills. The newly shaped fills are inverted U-shape cross-sectional splash fill and film fill with ripple plates. The obtained results show that the performance is affected by the type and arrangement of the fills. The modified splash fill has increased the wetted surface area of fill within the same volume compared to regular fills. The film fill with ripple plates has been used such that water from the distribution device ran down on both surfaces of each ripple plate. By the arrangement of ripple plates, cooling loss by premature dropping off of water has been avoided. Performance factors like range, approach, effectiveness, cooling capacity, evaporation loss, percent loss are calculated from...
The present paper describes the designing of a thermally and economically optimum mechanical draft counter-flow wet cooling tower. The design model allows the use of a variety of packing materials in the cooling tower toward optimizing heat transfer. Once the optimum packing type is chosen, a compact cooling tower with low fan power consumption is modelled within the known design variables. Moreover, a simulation model of the cooling tower is developed for studying the tower's performance as the main component of a water cooling system. The model also allows the influence of the environmental conditions on the thermal efficiency of the cooling tower to be considered. The thermal performance of the cooling tower is simulated in terms of varying air and water temperatures, and of the ambient conditions. The model is tested against experimental data. The suggested design and simulation algorithms of cooling tower are computed using Visual Studio.Net 2003 (C++).
CFD simulation of wet cooling towers
Applied Thermal Engineering, 2006
Heat and mass transfer inside a natural draft wet cooling tower (NDWCT) have been investigated numerically under different operating and crosswind conditions. The three-dimensional CFD model has utilized the standard k-e turbulence model as the turbulence closure. The current simulation has adopted both the Eulerian approach for the air phase and the Lagrangian approach for the water phase. The film nature of the water flow in the fill zone has been approximated by droplets flow with a given velocity. The required heat and mass transfer have been achieved by controlling the droplet velocity. At that specific droplet velocity, effects of the following operating parameters on the thermal performance of the NDWCT have been investigated: droplet diameter, inlet water temperature, number of nozzles, water flow rate and number of tracks per nozzle. As a result, the effect of crosswind velocity on the thermal performance has been found to be significant. Crosswinds with velocity magnitude higher than 7.5 m/s have enhanced the thermal performance of the NDWCT. (M. Behnia). 1 Tel.: +61 2 9036 9518; fax: +61 2 9036 9519; Mobile: +61 414 369 518. www.elsevier.com/locate/apthermeng Applied Thermal Engineering 26 (2006) 382-395
Thermal performance analysis of a closed wet cooling tower
Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering, 2007
A detailed model was developed and employed to examine the thermal performance of a closed wet cooling tower. The model is capable of predicting the variation of air thermodynamic properties, sprayed and serpentine water temperature as well as heat transfer rates exchanged between air and falling water stream inside the indirect wet cooling tower. The reliability of simulations was tested against experimental data obtained from the literature. A parametric study was conducted to evaluate the thermal behaviour of the indirect cooling tower under various air mass flowrates, serpentine water mass flowrates and inlet temperatures. The results of the theoretical investigation revealed an increase in cooling capacity and percentage loss of sprayed water due to evaporation, with increasing air mass flowrate. On the other hand, the increase of serpentine water mass flowrate resulted in slight increase in the overall temperature reduction of serpentine water. The effect of variable serpentine water inlet temperature on thermal performance of the indirect wet cooling tower was insignificant compared to other cases. Thermal performance analysis of a closed wet cooling tower Proc. IMechE Vol. 221 Part E: J. Process Mechanical Engineering JPME119 © IMechE 2007 Thermal performance analysis of a closed wet cooling tower JPME119
Experimental investigation of air side pressure loss for wet-cooling tower fills
Thermal Science, 2018
The pressure loss of air-flow in the cooling tower was measured experimentally with three different type cooling tower fill materials. Air mass flux (3.13 < Ga , < 5.21 kg/m2s), water mass flux (2.43 < Gw , < 5.21 kg/m2s) and height of the fill material (0.6, 0.8, and 1 m) were used as variable parameters for experimental works. Film, curler and splash type fillings were tested in the forced draft counter flow cooling tower unit which has 0.4 ? 0.4 m2 cross-section area. Experimental results were presented graphically. However, these results correlated for each type cooling tower fill material. The pressure loss was increased with increasing air mass flux. The pressure loss of film type filling is 29.1% higher than splash type.
Energies
In the present study, experimental investigation is carried out on two different kinds of packing materials (fills). PVC fills that are traditionally used in the industry are compared and analyzed against the cellulose-based paper fills. Different mass flow rates of air are used to study the effect of the flow rate of air on the forced draft cooling tower. The volume flow rate of water also varied, and the range of the cooling tower, along with efficiency, was analyzed. Along with these two parameters, the effect of inlet water temperature on the performance of the tower was studied. Cooling tower efficiency was plotted against different L/G ratios ranging from 0.95 to 7.67. Results showed that the type of packing has a significant impact on the cooling tower performance. Paper fills gave a maximum cooling tower efficiency and range equal to 93.12% and 16.5 °C, respectively. The optimal L/G ratio range of 0.96 to 1.44 was identified as the point at which the cooling tower demonstrat...