1000100001e51e61e71e80.010.020.050.1laminar, 64/Recriticalzone0.050.020.010.0040.0010.00025e-051e-05smoothrelative roughness e/DReynolds number Re = rho V D / muDarcy friction factor fMoody diagram: the critical zone is left blank because it is unknownlaminar, 64/Re