Viscous friction is the fiction, or resistance to relative motion, between adjacent layers of liquid. The resistance of motion between these oil layers is called viscous friction.
粘性是液体流层问相对运动而产生的摩擦力或阻力。油层间所产生的运动阻力称为粘性摩擦力。
2
Analysis of bubble motion in the flow field was used to develop relations for the viscous stresses, turbulent stresses, and interfacial momentum exchange to close the model.
Thus instead of Boltzmann equation this model equation may be approximately used to discuss the motion of gases in the transient region between molecular flow and viscous flow Iimits.