Drag Coefficients of Locomotion over Viscous Soils

A supersaturated viscous mud overlaying a hard bottom material is often critical to locomotion in many areas. To determine the drag of a wheel or track moving through mud, the familiar concepts of hydrodynamics pertaining to incompressible viscous fluids may be applied. A correlation between theory and experiment is indicated. The basic problem to be solved is one of viscous flow around a partially submerged object. The variation in pressure resulting from the friction drag causes a bulldozing effect in front of the wheel, and a resulting wake behind the wheel. The pressure drag may be reduced by streamlining the wheel which reduces both the amplitude of the pressure wave and the width of the trailing wake. A comparison between various wheel forms has been made and presented in chart form.