Abstract: On the basis of previous researches on velocity distribution and wall shear stress in wall jet region, the boundary layer development and wall resistance coefficient in hydraulic jump region is studied through the boundary layer momentum integral equation, and according to momentum equation, the calculation method for conjugate depth of hydraulic jump in consideration of wall resistance is obtained. Research shows that in hydraulic jump region, the thickness of boundary layer increases along the flow. The wall resistance coefficient is mainly a function of roller length, depth and Froude number before the hydraulic jump, as well as kinematic viscosity coefficient. Hydraulic jump conjugate depth ratio is a function of Froude number before the hydraulic jump and wall resistance coefficient. Formulas of boundary layer development, conjugate depths of hydraulic jump and wall resistance coefficient are put forward, and the wall resistance coefficient is used to calculate hydraulic jump conjugate depths. The calculation formula is verified by test data from F.G.Carollo and W.C.Hughes, which proves that it has reasonable form, comprehensive parameters, simple calculation and sufficient accuracy.

Key words: hydraulics, wall resistance, conjugate depths, boundary layer, roller length