Contents - Index


K_Returnbend



The K_Returnbend(RelRough) function returns the resistance coefficient for a return bend.  The relative roughness must also be supplied as a parameter.  This parameter can range between 0 (for smooth tubes) to 0.05 (for very rough tubes.)  The dependence of relative roughness indicates that the resistance factor is applicable to turbulent flow.

Example:
$UnitSystem SI K Pa J 
$VarInfo DELTAP units=Pa
$VarInfo h_L units=m
RelRough=0
K=k_returnbend(RelRough)
V_tilde=10 [m/s]
rho=1000 [kg/m^3]
g=g#
h_L=K*V_tilde^2/(2*g)
DELTAP=h_L*rho*g

{Solution:
DELTAP=15069 [Pa]
h_L=1.537 [m]
K=0.3014 
}

Reference:
Flow of Fluids Through Valves, Fittings, and Pipe, Crane Valves North America, Technical Paper No. 410M. 1979, p A-29


Minor Losses Index