某一圓形有壓油管的直徑為d=150mm,流速v=0.256m/s,長(zhǎng)1km,雷諾數(shù)Re=1921,其沿程損失hf為()
A.74.25cm油柱 B.74.25mH2O C.95.26cm油柱 D.62.26m油柱
半圓形明渠如圖所示,半徑r=4m,其水力半徑R為()
A.4m B.3m C.2.5m D.2m
水管直徑d=100mm,管中流速v=1m/s,運(yùn)動(dòng)粘度v=1.31×10-6m2/s,管中雷諾數(shù)為()
A.54632 B.67653 C.76335 D.84892