吸收器在吸收式冷卻系統中是相當重要的一環，因為其對於整體之效能有著極為顯著的影響。就吸收器而言，吸收劑以下落液膜之形式運作於吸收器表面藉以增加與水氣接觸之面積並提高吸濕率，而眾多文獻也指出波動液膜之吸濕效率較平滑液膜為佳。本研究主要是設計一波動液膜產生裝置，探討擾動頻率與吸濕率之關係，並嘗試用雷射位移感測計將擾動頻率對液膜之影響作定性分析。結果顯示當擾動頻率在30Hz吸收器具有最佳之吸濕效率。根據流場觀測及雷射位移感測器之訊號，顯示出在此頻率下波動液膜約為二維波之型態且具有較大之振幅。

The absorber plays a fairly important role in the absorption
refrigeration system because it significantly influences the performance of the entire system . For an absorber , the absorbent is falling in form of liquid film in order to increase the contact area with the water vapor and , therefore , the absorption rate . Numerous studies have indicated that wavy films result in better absorption rate than smooth laminar films . The aim of the present research is to design a device to trigger wave films falling on a flat plate absorber of a lithium bromide absorption refrigeration system , and to investigate the relation between the absorption rate and the frequency of disturbance . Effects of the controlled-disturbance on the liquid films are studied qualitatively using a laser displacement sensor . Results show that the best absorption rate is presented at the disturbing frequency of 30Hz . Observations of the flow field and the signals of the laser displacement sensor show that , at this frequency , solitary waves are approximately two-dimensional and have large amplitudes .

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