Generally, evaporative water cooling towers include an upper hot water distribution system, for example, a system comprising a series or water distribution nozzles or an apertured distribution basin or the like, and an opposing cold water collection basin positioned at the base or bottom of the cooling tower. Commonly, a splash-type water dispersing fill structure is disposed in the space between the hot water distribution system and the underlying cold water collection basin. The aforementioned fill structure oftentimes includes either a plurality of elongated, horizontally arranged and staggered splash bars supported at spaced intervals by an upright grid structure or frame assembly, or a series of fill packs composed of a number of film fill sheets. During operation of the evaporative cooling towers as previously described, typically, hot water is distributed or disposed onto the fill structure, e.g., the bars or packs, wherein the water disperses onto the bars or packs, forming droplets. This forming of droplets helps to facilitate the heat exchange process. At the same time, cooling air currents are drawn through the fill structure, either by means of a motor driven fan or through use of a natural draft-inducing hyperbolic tower.
The fill structure of a given tower functions to promote interactive thermal interchange between the water and air. As water droplets are discharged from the distribution system as previously described, the temperature difference between the relatively warm water and the cooling air causes evaporation on the surface of the droplets. Therefore, the cooling of the water typically occurs at a rapid rate. However, as the surface temperature of individual droplets approaches the wet bulb temperature of the surrounding air, the cooling process is diminished and is dependent upon the rate of heat transfer from the inside of the droplet to the outside of the surface thereof. As such, it is desirable to interrupt the fall of individual droplets by splashing the drops on a fill bar or the like. This interruption can cause additional, new water surfaces to be exposed and, in some cases, subdivide the droplets into smaller droplets, increasing the total water surface area available exposed to the passing air.
Splash bars utilized in evaporative cooling towers must meet several criteria in order for the evaporative cooling towers in which they are employed, to operate and perform correctly. First, it is desirable for the splash bar to provide consistent, predictable dispersal and breakup of the water droplets over a range of water loadings typically encountered during operation of the evaporative cooling tower. Second, it is desired that the descending droplets be uniformly broken into relatively fine particles in a widely divergent pattern to facilitate enhancement of the heat exchange process. Third, it is desired that the splash bar design cause minimum air pressure drop in order to keep fan horsepower requirements and operating costs at relatively low levels. Fourth, the splash bar design should have sufficient structural strength to span large distances between adjacent upright grid supports, since deflection of the bars can enable the water to channel toward the low part of the bar, thereby causing coalescence of water and unequal water dispersal throughout the passing air streams. And finally, cost is an important consideration in the selection and fabrication of splash bars as large evaporative cooling towers employ a very large volume of splash bars for heat exchange purposes. Thus, it is desirable to manufacture splash bars from materials that are both structurally sound and economically reasonable.
Accordingly, there is a need in the art to provide an improved splash bar apparatus that provides increased heat exchange performance. Furthermore, there is a need in the art to provide a an inexpensive splash bar that has sufficient structural strength to resist deflection, while providing increased heat exchange performance.