Sizing cooling towers

The effects of wet bulb, approach and range on mecbanical draft cooling tower size is indicated in Figure 9-118. 

Maze. R. W. Hydrocarbon Process., 46(2) (1967) 123. Practical tips on cooling tower sizing. 

Relative cooling tower size is sensitive to the difference between the exit and wet bulb temperatures ... 

Figure 5.9 Effect of flow variance on cooling tower size factor.

The approach has a significant effect on the tower size, as shown in Figure 5.11. For a given heat load, gpm and wet-bulb temperature, the cooling tower size increases as the approach decreases, and the closer the cold water temperature approaches the wet-bulb temperature, the greater the increase in the cooling tower size. 

Practical Tips on Cooling-Tower Sizing Maze, R. W. 

For economic reasons, equilibrium conditions cannot be approached closely. In a cooling tower, for instance, the effluent air is not quite saturated, and the water temperature is not quite at the wet bulb temperature. Percent saturation in the vicinity of 90% often is feasible. Approach is the difference between the temperatures of the water and the wet bulb. It is a significant determinant of cooling tower size as these selected data indicate ... 

Table 3-5. Approach vs. Cooling Tower Size and Price...

Table 3-7. Range With Variable Heat Load vs. Cooling Tower Size...

Maze, R.W. Practical Tips on Cooling Tower Sizing. Hydrocarbon Processing, February 1967, p. 123. Vahlsing, D.H. Once-Through vs Cooling Tower Water. Hydrocarbon Processing, July 1967, p. 167. 

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