ME 322 – Mechanical Engineering Thermodynamics
Spring 2016
Homework #9
MULTI-CHOICE (circle all correct answers; supply supporting reasoning if in doubt)
9-1 What are valid units of the universal gas constant, Ru?
a) Btu/(lbm-R)
b) kJ/(kg-K)
c) kJ/(kgmol-K)
d) ft-lbm/(lbmol-R)
9-2 Which of the following quantities have MLt units of L2/t2?
a) kinetic energy
b) specific heat transfer
c) specific work transfer
d) potential energy
9-3 What is the thermodynamic name for a process where enthalpy is constant?
a) adiabatic
b) aergonic
c) isentropic
d) isenthalpic
9-4 Which are valid expressions for work of an ideal gas during an isobaric process?
a) p (V2-V1)
b) V (p2-p1)
c) mR(T2-T1)/(1-n)
d) ʃp dV
PROBLEMS
Solve 3.48 from the course textbook using EES for a range of ending pressures extending from
2.00 MPa to atmospheric pressure. Plot the resulting steam quality as a function of ending
pressure. Use EES to create a p-H (pressure-enthalpy) diagram for water that focuses on
saturation behavior up to the critical point. Illustrate/explain how you can use this chart to
validate your solution to 3.48.
Solve 3.55 from the Balmer text using EES. Verify your answers against those from the
thermodynamic tables supplement. Discuss issues you encountered with each method.
Note: On the course website you will find examples in the required homework format for EES
Solutions. Please look these over as you prepare your solution.
Homework is due at the beginning of the next class period, unless specified otherwise
on the course website. Homework not handed in at the beginning of the class period is
late and will not be graded.