Air outlet temperature issue of the air cooler

Your question should take into account the pressure parameters in the air cooler. The key point for operation should be whether the parameters required by the downstream users of the air cooler meet the specifications. “There are limits on the supply and return water temperatures for circulating water! ”All factors are designed to serve the end-users of the air cooler.

First of all, the question you raised is very meaningful and extremely important. The difference between the outlet temperature and the ambient (i.e., inlet) temperature is essentially the temperature difference between the air at the inlet and outlet. The greater the temperature difference between the air inlet and outlet: 1. Advantage: Less air (from the blower) is required, which means lower power consumption for the blower. 2. Disadvantage: The heat transfer temperature difference (driving force) is also reduced, resulting in an increased area for the air cooler. Therefore, the temperature difference between the air inlet and outlet needs to be balanced, taking the following principle into account: 1. In most cases, the temperature difference between the air inlet and outlet should not exceed 5 ℃ ； 2. If the area of the air cooler is very large, consider reducing the temperature difference between the inlet and outlet air to decrease the size of the air cooler ； 3. The windward speed for most applications should not exceed 3.5 m/S; otherwise, the pressure loss will be too high, requiring a higher air pressure from the blower. In short, these are all principles. However, in actual design, these adjustments require extensive thermodynamic and fluid dynamics calculations. Manual optimization is extremely tedious, and it’s not something modern people do. It is recommended to use BoxHeater for design: https://bbs.hcbbs.com/thread-1003595-1-1.html

Air outlet temperature, how do you want to limit it? The outlet temperature is the result of cyclic calculations and represents an approximate value; the closer it is to the actual test results, the more advanced your calculation program and the parameter choices are. It can be determined here that the outlet temperature will not be higher than the inlet temperature of the circulating water; however, this is not a limitation but rather a natural law of heat exchange.

HTRI can perform well; sometimes the outlet temperature can reach over 100 degrees. I’m not sure if that’s feasible

I disagree with the claim that the temperature difference between the air inlet and outlet should not exceed 5 degrees; in most cases, this difference does exceed 5 degrees. In the air coolers I have designed over the past few years, the temperature rise of the air has been above 10 degrees. The increase in air temperature by a few degrees is determined by whether there is cooling or condensation on the inside of the tube, based on the difference from the air temperature. The lower the increase in air temperature, the greater the volume of air required, the smaller the area needed, and the higher the operating costs.