管式蒸发空冷使用增膜板的强化传热

增膜板是管式蒸发空冷器中的新型强化传热元件。管子上的水落到增膜板上铺展成膜，增大了水与空气的换热面积，由此使落到下一层管子上的水的温度降低，使得下一层管子的内外温差得以扩大，强化了下一层管子的传热。在1．5m×3Wi中试装置上对光管管束与增膜板管束进行了换热对比实验，结果表明，在相同实验条件下增膜板管柬蒸发空冷器的传热量可比光管管束空冷器至少增加20％。达到一定传热效果后，喷淋量加大，传热量并不明显增加。在一定风量范围内，增加风量可明显提高空冷器传热效率。

Effects of Enhancing Heat Transfer of Using Film Sheet in Tubular Evaporative Air Cooler

Film sheet is a new type of element to enhance heat transfer in tubalar evaporative air cooler. The water from the tube drops down on the film sheet and spreads to form the film on the sheet,so that the heat exchanging area between the water and air is increased. The temperature is decreased as water dropping to the lower tube below the sheet. The temperature difference between inner tube and outer tube becomes larger, enhancigng the heat transfer of the lower tube below the sheet. The experiments have been made in a pilot device with demension of 1.5 m × 3 m. The heat transfer quantity of the bundle with film sheets goes up by 20% over the bare tube bundle.