Backward Curved Blades First case, if beta is less than 90 degree. Since second term in LHS of head vs flow equation is positive in this case, pressure head decreases with increase in flow. These kinds of impellers are called backward curved.
Backward Curved BladesFirst case, if beta is less than 90 degree. Since second term in LHS of head vs flow equation is positive in this case, pressure head decreases with increase in flow. These kinds of impellers are called backward curved.