The Darcy-Weisbach Equation Notes The Darcy-Weisbach equation is now considered the best empirical relation for pipe-flow resistance. In terms of head units it is, (pipe friction) where, hl is the head loss, f is the friction factor, L is the pipe length, V is the average flow velocity, and g is the acceleration of gravity. In terms of pressure drop, Dp it is, where r is the fluid … Read more
Coefficients of Friction Materials Coeff. of Static Friction s Coeff. of Kinetic Friction k Steel on Steel 0.74 0.57 Aluminum on Steel 0.61 0.47 Copper on Steel 0.53 0.36 Rubber on Concrete 1.0 0.8 Wood on Wood 0.25-0.5 0.2 Glass on Glass 0.94 0.4 Waxed wood on Wet snow 0.14 0.1 Waxed wood on … Read more
Classical Plate Equation Notes The small transverse (out-of-plane) displacement w of a thin plate is governed by the Classical Plate Equation, where p is the distributed load (force per unit area) acting in the same direction as z (and w), and D is the bending/flexual rigidity of the plate defined as follows, in which E is the Young’s modulus, is the Poisson’s ratio of the plate material, … Read more