The purpose of the regenerative heat exchanger is to essentially recycle the heat rejected in step (B) as heat absorbed in step (D). Show why this works for the case of a general working fluid with heat capacity, Cv(T). The Stirling engine (invented in 1816 by Robert Stirling) is a heat engine that produces work through cyclic compression and expansion of a gaseous working fluid, such as hot air. An idealized cyclic process, aptly named the Stirling Cycle, for such an engine consists of four steps: (A) isothermal expansion at the hot reservoir temperature, Th, (B) isochoric (constant volume) heat rejection to a regenerative heat exchanger, (C) isothermal compression at the cold reservioir temperature Tc, and (D) isochoric heat absorption from the regenerative heat exchanger back to the initial state.

The purpose of the regenerative heat exchanger is to essentially recycle the heat rejected in step (B) as heat absorbed in step (D). Show why this works for the case of a general working fluid with heat capacity, Cv(T). The Stirling engine (invented in 1816 by Robert Stirling) is a heat engine that produces work through cyclic compression and expansion of a gaseous working fluid, such as hot air. An idealized cyclic process, aptly named the Stirling Cycle, for such an engine consists of four steps: (A) isothermal expansion at the hot reservoir temperature, Th, (B) isochoric (constant volume) heat rejection to a regenerative heat exchanger, (C) isothermal compression at the cold reservioir temperature Tc, and (D) isochoric heat absorption from the regenerative heat exchanger back to the initial state.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

A steady-state gas turbine is using air as the working fluid has shaft power output of 55 MW. Air enters the turbine at 300 K and leaves at 600 K and 30 m/s. The air is first compressed by adding a compression power of 15 MW. Then air receives 173 MW as heat input from the combustor. Determine the mass flow rate of air in kg/s.
A regenerative steam cycle renders A. increased work output per unit mass of steam В. decreased work output per unit mass of steam C. increased thermal efficiency decreased work output per unit mass of steam as D. well as increased thermal efficiency
Air within a piston-cylinder assembly executes a Carnot heat pump cycle, as shown in the figure below. For the cycle, TH = 400 K and Tc = 300 K. The energy rejected by heat transfer at 400 K has a magnitude of 625 kJ per kg of air. The pressure at the start of the isothermal expansion is 325 kPa. Tc p-v diagram for a Carnot gas refrigeration or heat pump cycle. Assuming the ideal gas model for the air, determine: (a) the magnitude of the net work input, in kJ per kg of air, and (b) the pressure at the end of the isothermal expansion, in kPa.
A heat pump cycle using water as the working fluid consists of a compressor, a condenser, an expansion valve, and an evaporator. Saturated vapor with mass flow rate of 1 kg/s at 0.5 MPa (state 1) enters the condenser and leaves it as saturated liquid at the same pressure (state 2). The pressure in the evaporator is 0.01 MPa. The condenser and the evaporator processes are isobaric. The compressor is adiabatic and reversible. The valve is adiabatic. A. List all the known information and assumptions. B. Determine the heat output of the condenser (QH) C. Determine the heat input of the evaporator(Qc) D. Determine the coefficient of performance of the heat pump. E. Determine the coefficient of performance of a Carnot heat pump running between the same temperatures TH and TC at the evaporator and condenser. F. Calculate the entropy generation in the compressor. G. Draw the TS diagram for the cycle on paper. (Hint: you must calculate T1, T2, T3, T4, h1, h2, h3, h4, s1, s2, s3, s4, and draw…
An r-134a refrigerator operates a simple vapor compression cycle (SVCC). The evaporatoroperates at -10 °C, while the condenser operates at 1 MPa. R-134a flows around the system at 10 g/s.a. Graph the cycle in a P-h diagram and calculate the temperature at the exit of the compressor, assuming it is 100% isentropicallyefficient.b. Calculate the power required by the compressor (in W) and the cooling effect of the refrigerator (in kW) c. Compute for the COP of the system. What is its percent difference from the reversible efficiency?
Q.5 A standard vapor compression cycle uses R134a as the refrigerant. The condensing and evaporating temperatures are 40°C and 0°C respectively. The isentropic efficiency of the compressor is 80%. The refrigerant flow rate is 0.35 kgs. Calculate (i) the heat absorption rate, (ii) the work input to the compressor, and (iii) the COP of the cycle. Answers: (i) 49.7 kW, (ii) 11.33 kW, (iii) 4.39| Nihal E wijeysuuга Heabins principles of ventilation air conditio win and
Superheated steam at 18 MPa, 560 °C enters the steam turbine. The pressure at the exit of the turbine is 0.06 MPa and saturated liquid water leaves the condenser at 0.06 MPa. Pressure is increased to 18 MPa again after the pump. Find: (a) Sketch the process on a T-s diagram. (b) The net work per unit of steam flow in kJ/kg. (c) Heat transfer to steam passing through the boiler, in kJ/kg.
(A) the net heat energy absorbed during a cyclic process (the difference between heat flowing into the system and heat leaving the system) is the work. If we regard the atmosphere as a heat engine, what is the work being done by the atmosphere? That is, what phenomenon or phenomena are a realization of the work being done by the atmosphere? (B) Of all possible heat engines, the Carnot cycle has the maximum efficiency between any two operating temperatures (think of these temperatures as the maximum and minimum temperatures encountered during the cycle). Estimate the Carnot efficiency of Earth's atmosphere. [Hint: Think about the temperature variation with latitude.] (C) Do you think the efficiency of the real atmosphere would be "close" or "far" from the Carnot efficiency? Please explain your answer.
5- A (293 MW) steam power plant of the pressurized-water Nuclear reactor type uses Once-Through circulating system from a river. Regulation do not permit cooling water discharge back to the river hotter than (5 C°) above river temperature. If the plant thermal efficiency is (33 %). Estimate the following:- a. The cooling water mass flow rate b. The percentage reduction in this water flow if the plant efficiency is improved by(1 %).
In a gas turbine power plant, air at 10°C and I bar is compressed to a pressure of 4 bar by a compressor. The air is then heated in a 100% efficient heat exchanger and in the combustion chamber to a temperature of 700°C. heat exchanger and the combustion chamber is 0.14 bar. Calculate the power plant efficiency.
Q.2/ Consider a Carnot cycle executed in a closed system with air as the working fluid. The maximum pressure in the cycle is 1300 kPa while the maximum temperature is 950 K. If the entropy increase during the isothermal heat rejection process is 0.25 kJ/kg·K and the network output is 100 kJ/kg, knowing that R= 0.287 kJ/kg.K and y= 1.4, what is the thermal efficiency of the cycle?