Air-cooled heat exchanger inlet flow losses

The primary purpose of this experimental investigation is to determine the influence that differences in air-cooled heat exchanger geometry have on heat exchanger inlet air flow losses. Heat exchanger geometry would not only include details pertaining to the heat exchanger finned tubes, but also the orientation of the heat exchanger finned surfaces with respect to the inlet air flow as well as to the inlet air angle of incidence on the heat exchanger. It is found that the inlet air flow losses are independent of the average air velocity through the heat exchanger. Inlet air flow losses increase with a decrease in the inlet air angle of incidence. The orientation of the heat exchanger finned surfaces has an effect on the inlet air flow losses and is primarily a function of the tube cross-sectional profile of the finned tubes. An equation based on the experimental results is formulated to calculate the heat exchanger inlet air flow losses. It is also shown that the geometric details of the heat exchanger finned tubes or heat exchanger core used in the construction of the heat exchanger could have a pronounced effect on the inlet air flow losses.