INNER WALL SURFACE STRUCTURE FOR FLOW CHANNEL, AND HEAT EXCHANGE SYSTEM

• Main Authors: SATO NORIKAZU, INAGAKI MASAHIDE, HASEGAWA MANABU, YAMAMOTO MICHIYASU
• Format: Patent
• Language: English; Japanese
• Published: 20.07.2017
• Subjects: BLASTING; DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OFGENERAL APPLICATION; HEAT EXCHANGE IN GENERAL; HEATING; LIGHTING; MECHANICAL ENGINEERING; WEAPONS

PROBLEM TO BE SOLVED: To reduce water conduction resistance while maintaining or improving a heat transfer quantity.SOLUTION: The present invention relates to an inner wall surface structure 10 for a flow channel including multiple wavy riblets 14 which are formed on an inner wall surface of a flow channel 12 and formed in a meander shape extending in a length direction of the flow channel 12. When the Nusselt number in the flow channel 12 in the case where the inner wall surface of the flow channel 12 is a smooth surface is defined as Nu, the Nusselt number in the flow channel 12 in the case where the multiple wavy riblets 14 are formed on the inner wall surface of the flow channel 12 is defined as Nuand HTR that is a heat transfer ratio in the flow channel 12 is represented by an expression (1), a wavelength and an amplitude of the multiple wavy riblets 14 are set in such a manner that the heat transfer ratio in the flow channel 12 satisfies HTR>1. Thus, water conduction resistance can be reduced by reducing a flow rate just for heat transfer promotion while maintaining or improving a heat transfer quantity.SELECTED DRAWING: Figure 1 【課題】伝熱量を維持又は向上させながら通水抵抗を低減する。【解決手段】本発明は、流路１２の内壁面に形成されると共に流路１２の長さ方向に延びる蛇行形状とされた複数の波状リブレット１４を有する流路の内壁面構造１０に関する。流路１２の内壁面が平滑面である場合の該流路１２におけるヌセルト数をＮｕｆｌａｔとし、流路１２の内壁面に複数の波状リブレット１４が形成された場合の該流路１２におけるヌセルト数をＮｕｒｉｂｌｅｔとし、流路１２における熱伝達率比であるＨＴＲを式（１）で表した場合に、流路１２における熱伝達率比がＨＴＲ＞１となるように、複数の波状リブレット１４の波長及び振幅が設定される。これにより、伝熱量を維持又は向上させながら、伝熱促進した分だけ流量を下げることにより通水抵抗を低減することができる。【選択図】図１