ENGR 335
KEY WORDS AND STUDY QUESTIONS FOR CH 7
energy equation heat transfer rate HGL
kinetic energy shaft work rate EGL
potential energy flow work rate pump head
internal energy static pressure turbine head
enthalpy pump work rate pressure head
blower work rate velocity head
mechanical energy fan work rate piezometric head
thermal energy turbine work rate total head
kinetic energy correction factor pump efficiency head loss
pipe flow energy equation turbine efficiency
extended Bernoulli equation
1. Discuss the kinds of flows for which the pipe flow energy equation (eqn. 7.24) can be used.
Give two examples of pipe flows where it will not work.
2. Write the relationship between, (a) pump head, hp, and power to drive the pump, and (b) turbine
head, ht , and power produced by the turbine. Include pump efficiency and turbine efficiency in
these relationships.
3. What is the fundamental cause of hL? Is hL always positive?
4. What equations should be used to relate pressure and velocity at the inlet and outlet of a nozzle?
Discuss assumptions.
5. Give the sign conventions for heat transfer and shaft work.
6. Under what conditions does the pipe flow energy equation reduce to the Bernoulli equation?
7. Under what conditions are the HGL and EGL coincident?
