短語詞組短語diameter height ratio 逕高比well diameter enlargement ratio 井逕擴大率diameter reduction ratio 縮逕比Diameter Thickness Ratio 逕厚比hole diameter enlargement ratio 井逕擴大率blade diameter length ratio 葉片逕高比borehole diameter enlargement ratio 井逕擴大率length diameter ratio 長度直逕比;長逕比lift diameter ratio 陞力直逕比 返回 diameter ratio