A Power cycle operates between two temperature reservoirs 20oC and 1200oC. The cycle receives 1000 kW of heat from the high-temperature reservoir and has a thermal efficiency of 60%, Find: (a) The Power generated. (b) The Carnot cycle efficiency if operating between the same two temperature reservoirs.

A Power cycle operates between two temperature reservoirs 20oC and 1200oC. The cycle receives 1000 kW of heat from the high-temperature reservoir and has a thermal efficiency of 60%, Find: (a) The Power generated. (b) The Carnot cycle efficiency if operating between the same two temperature reservoirs.

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter4: The Second Law Of Thermodynamics

Section: Chapter Questions

Problem 77AP: A heat engine operates between two temperatures such that the working substance of the engine...

See similar textbooks

Similar questions

Is it possible for a system to have an entropy change if it neither absorbs nor emits heat during a reversible? transition? What happens it the process is irreversible?
A Carnot engine operates between 550 and 20 baths and produces 300 kJ of energy in each cycle. Find the change in entropy of the (a) hot bath and (b) cold bath, in each Carnot cycle?
Check Your Understanding A Carnot engine operates between reservoirs at 400 and 30 . (a) What is the efficiency of the engine? (b) If the engine does 5.0 J of work per cycle, how much heat per cycle does it absorb from the high-temperature reservoir? (c) How much heat per cycle does it exhaust to the cold-temperature reservoir? (d) What temperatures at the cold reservoir would give the minimum and maximum efficiency?
An ideal diesel cycle is shown below. This cycle consists of five strokes. In this case, only air is drawn into the chamber during the intake stroke OA. The air is then compressed adiabatically from state A to state B, raising its temperature high enough so that when fuel is added during the power stroke BC, it ignites. After ignition ends at C, there is a further adiabatic power stroke CD. Finally, there is an exhaust at constant volume as the pressure drops from pD to pA , followed by a further exhaust when the piston compresses the chamber volume to zero. (a) Use W=Q1Q2, Q1=nCp(TCTB) , and Q2=nCv(TDTA) to show that e=WQ11TDTA(TCTB). (b) Use the fact that AB and CD are adiabatic to show that e=11( V C V D )( V B V A )( V C V D )( V B V A ). (c) Since there is no preignition (remember, the chamber does not contain any fuel during the compression), the compression ratio can be larger than that for a gasoline engine. Typically, VA/VB=15 and VD/VC=5 . For these values and =1.4 , show that =0.56 , or an efficiency of 56%. Diesel engines actually operate at an efficiency of about 30% to 35% compared with 25% to 30% for gasoline engines.
If a refrigerator discards 80 J of heat per cycle and its coefficient of performance is 6.0, what are (a) the quantity off heat it removes per cycle from a cold reservoir and (b) the amount of work per cycle required for its operation?
Consider an ideal gas Joule cycle, also called the Brayton cycle, shown below. Find the formula for efficiency of the engine using this cycle in terms of P1 , P2 and .
A Carnot engine has an efficiency of 0.60. When the temperature of its cold reservoir the efficiency drops to 0.55. If initially Tc=27, determine (a) the constant value of Th and (b) the final value of Tc.
A cylinder contains 500 g of helium at 120 atm and 20 . The valve is leaky, and all the gas slowly escapes isothermally into the atmosphere. Use the results of the preceding problem to determine the resulting change in entropy of the universe.
A Carnot engine operates in a Carnot cycle between a heat source at 550 and a heat sink at 20 . Find the efficiency of the Carnot engine.
What type of processes occur in a Carnot cycle?
Suppose 20 g of ice at 0 is added to 300 g of water at 60 . What is the total change in entropy of the mixture after it reaches thermal equilibrium?
An engine is found to have an efficiency of 0.40. If it does 200 J of work per cycle, what are the corresponding quantities of heat absorbed and discharged?