著者

米須 清一郎 松田 昇一 加藤 純郎

出版者

一般社団法人 日本機械学会

雑誌

年次大会

巻号頁・発行日

vol.2017, 2017

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<p>Impingement jets are often used for the cooling and heating of a surface or a body because a high heat transfer coefficient is obtained near the stagnation point of an impingement surface. Recently, as equipment becomes smaller, impingement jets have been utilized in narrow spaces. In such a case, the nozzle diameters and Reynolds number which based on the nozzle exit velocity also become tinier as a matter of course. Generally, in the case of measuring the heat transfer coefficient by using a thin heat transfer surface, heat loss, <i>q</i>_e due to heat conduction in the in-plane direction in the heating surface occurs. However, <i>q</i>_e has been considered inconsequential in the case of the common impinging jets having large diameters and with large Reynolds number. However, <i>q</i>_e may not be negligible in the case of impinging jets having a small diameter and with low Reynolds number. In this research, heat transfer characteristics using rows of impinging jets with small diameters and with low Reynolds number were investigated experimentally. The jet holes with the diameters <i>D</i> of 1, 2 and 3 mm were used. The experiments were performed with the relatively low Reynolds number range of 170~1460. The surface temperature of the impingement plate was measured using an infrared camera, from which heat transfer coefficients on the surface were obtained. It was found that the <i>q</i>_e needs to be considered in the case of impinging jets having small diameters and with low Reynolds number.</p>