This preview shows page 1. Sign up to view the full content.
Unformatted text preview: nozzle steadily at 280 kPa and 77°C with a
velocity of 50 m/s and exits at 85 kPa and 320 m/s. The heat
losses from the nozzle to the surrounding medium at 20°C are
estimated to be 3.2 kJ/kg. Determine (a) the exit temperature
and (b) the total entropy change for this process.
7–77 Reconsider Prob. 7–76. Using EES (or other)
software, study the effect of varying the surrounding medium temperature from 10 C to 40 C on the exit
temperature and the total entropy change for this process, and
plot the results. Reversible Steady-Flow Work
7–78C In large compressors, the gas is frequently cooled
while being compressed to reduce the power consumed by the
compressor. Explain how cooling the gas during a compression
process reduces the power consumption.
7–79C The turbines in steam power plants operate essentially under adiabatic conditions. A plant engineer suggests to
end this practice. She proposes to run cooling water through
the outer surface of the casing to cool the steam as it flows
through the turbine. This way...
View Full Document
This document was uploaded on 11/28/2012.
- Spring '09