The function of cooling towers can be explained in relation to the way our bodies use sweat to cool down. When our bodies get too hot, sweat evaporates and creates a cooling effect over our skin. This process lowers our internal body temperature and is the idea behind what makes a cooling tower work. However, there is more water to cool and evaporate in cooling towers than the small amount of sweat our bodies generate.
Cooling towers have fans to replace moisture saturated air, gear drives to operate the fans, water circulation devices, and a heat source to heat runoff. The following will help you better understand the thermal characteristics of cooling towers.
There are several factors that determine if a cooling tower will fit your industry’s needs, including water flow rate, inlet and outlet temperature, and wet bulb temperature. The most confusing of these factors can be the wet bulb temperature. This is the temperature used to figure the relative humidity, which usually changes throughout the day.
Relative humidity is found when the temperature of a dry thermometer is compared with the temperature of a wet bulb thermometer. The two thermometers will usually have different readings, but the water readings will be the same if the air is saturated with water. When 100% relative humidity is reached, the air will not accept any more water. The water on the bulb will not evaporate and the temperature will not read the same as the dry bulb.
The lower the reading on the wet bulb, the lower the relative humidity. With less humidity, the air can accept more moisture and the cooling tower can reject more heat. The size of the cooling tower you use should be determined by the max wet bulb reading.
Cooling towers do not control the rate of heat transfer, but can transfer the heat they are given. It does not matter how large or small a tower is, heat transfer and evaporation rates never vary. However, the size of the cooling tower, flow rate, and wet bulb temperature determine the inlet and outlet water temperatures.
The difference between the temperature of the inlet and outlet is not determined by the cooling tower itself. A tower could cool water from 90 to 80 degrees or 100 to 90 degrees, but the 10 degree difference is not affected by the cooling tower’s size. Although you cannot change the heat transfer rate, you can increase performance through boosting the cubic feet per minute or increasing the surface area.
Maintaining your cooling towers will save you money in operations and energy usage. For example, the less clean your tower is, the longer and harder it needs to work to achieve the same cooling goals. This issue increases stress on the entire system because it must operate at higher condensing pressures to satisfy the load. These increased stresses reduce the life of your tower and increase maintenance requirements, in turn causing you to spend more money.
Cooling towers, while strong machines, require detailed inspections to ensure that they are operating at peak efficiency. One of the most important components to maintain is the cooling tower gear drive. The experts at Amarillo Gear Service in Amarillo, Texas can help you maintain, clean, and repair your cooling tower gear drives. Call Us today at (806) 622-1273 or Contact Us by email to learn more. We will be glad to tell you more about the regions we service and the quality workmanship we can bring to the repair or renewal of your gear drives.
