短語詞組短語gravity air circulation 自鐮環(huán)gravity -circulation type heat pipes 重力式熱管gravity circulation lubrication 重力循環(huán)潤滑local flow gravity circulation 局部重力循環(huán)gravity circulation dry kil 自然循環(huán)干燥窯local gravity circulation 局部重力循環(huán)hot water gravity circulation 熱水重力循環(huán)fluid gravity circulation 流體重力循環(huán)gravity circulation of hot water 熱水重力循環(huán) 返回 gravity circulation