Chapter 8, Problem 8.30P

Prove that there is an increase in efficiency between a Simple Rankine Cycle and a Reheat Rankine Cycle. What is worth using for?

For a given Rankine Cycle, the ideal pump work involves an isentropic compression process. O True O False

an ideal Rankine cycle (fluid flow rate is 8 kg/s) operating between upper and lower pressures of 5 and 10,000 kPa. Draw a schematic of the components of this cycle. Draw the cycle on a P-v phase diagram and a T-s diagram. Find the power output of the turbine, the power input needed for the pump, and the overall cycle thermal efficiency.

in a rankine cycle, what is the entrance pressure of the turbine if the condenser pressure is 105 kpa and the pump work is 20 kj/kg. use density of water entering the pump, 950 kg/m^3.

Consider an ideal gas-turbine cycle with the following details in Table 1. Table 1 No. of stages at compression No. of stages at expansion 2 2 Pressure ratio 3 T of air at compressor inlet T of air at turbine inlet 300 K 1200 K Analyse the back work ratio and compare the thermal efficiency of the cycle for these two cases: i. no regenerator is used ii. a regenerator is used with 75 percent effectiveness

Steam enters the turbine 5MPa and 600 and exits adiabatically at 100 kPa. For Actual cycle: turbine efficiency =90%, turbine brake efficiency=84%, generator efficiency=93% Mass flow rate of steam = 15 kg/s Determine the following: For Ideal Rankine Engine Find WT and e  SR and HR  For Actual Rankine Cycle  Find WT’, WB, WK,e’, eB and eK  Find SR’, SRB, SRK,HR’, HRB and HRK

Exhaust gases from the turbine of a simple Brayton cycle are quite hot and may be used for other thermal purposes. One proposed use is generating saturated steam at 110C from water at 30C in a boiler. This steam will be distributed to several buildings on a college campus for space heating. A Brayton cycle with a pressure ratio of 6 is to be used for this purpose. Plot the power produced, the flow rate of produced steam, and the maximum cycle temperature as functions of the rate at which heat is added to the cycle. The temperature at the turbine inlet is not to exceed 2000C.

Steam enters the turbine 5MPA and 600 and exits adiabatically at 100 kPa. For Actual cycle: turbine efficiency =90%, turbine brake efficiency=84%, generator efficiency=93% Mass flow rate of steam 15 kg/s Determine the following: For Ideal Rankine Engine a. Find WT and e b. SR and HR b. For Actual Rankine Cycle a. Find WT', WB, WK,e', eB and eK b. Find SR', SRB, SRK,HR', HRB and HRK

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