An ideal reheatregenerative rankine cycle with an open. Software solutions by the same author, published by bookboon. The temperatures at the inlet of both turbines, and the thermal efficiency of the cycle are to be determined. The schematic and the ts diagram are shown on the left. Draw the schematic diagram of reheat rankine cycle as in figure 1. Solved an ideal reheat rankine cycle with water as the. Rankine cycle solved example support me through phonepe,paytm,tez my number. We often study the ideal cycle in which internal irreversibilities and complexities the actual intake of air and fuel, the actual combustion process. Problems with the are solved using ees, and complete solutions together. The reheat pressure can be determined from the requirement that the entropies at state 5 and state 6 be the same.
Consider an ideal steam reheat cycle where steam enters the highpressure turbine at 3. Intercooling, reheat, heatrecovery exchanger, example 4, combined cycles with heatrecovery. A steam power plant operates on an ideal reheat rankine cycle. Problems with the are solved using ees, and complete solutions together with. We introduced the basic steam power plant in chapter 4b, however we could only evaluate the turbine and feedwater pump after we introduced the concept of entropy in chapter 6a. Tutorial questions reheat rankine cycle slideshare. Steam enters the turbine at 3 mpa and 350c and is condensed in thecondenser at a pressure of 10 kpa. The condenser pressure, the net power output, and the thermal efficiency are to be determined. Heat is rejected to the surroundings at a rate of 8000 kw and air flow rate is 25 kgs. Use the water tables to determine the enthalpy at each state. Assuming a compressor efficiency of 80%, determine a net power output of the plant. The mass flow rate of steam through the cycle is 12 kgs. Further addition of energy causes evaporation of the liquid until. A steam power plant operates on an ideal reheat regenerative rankine cycle and has a net power output of 80 mw.
In this chapter we will consider ideal steam power cycles including isentropic turbines and pumps. Steam is superheated to 550 o c before it is expanded to the reheat pressure of 4. A high pressure ideal reheat steam power cycle we extend the above example to the more practical ideal reheat cycle as shown below. The ideal regenerative reheat cycle using an open feedwater heater. Brayton cycle problem with solution let assume the closed brayton cycle, which is the one of most common thermodynamic cycles that can be found in modern gas turbine engines.
The steam power plant operates on an ideal reheat regenerative rankine cycle with one open feedwater heater, one closed feedwater heater, and one reheater, as shown in the diagram. Software solutions vapor power cycles rankine cycle is a supplement to the partii of the popular, free ebook series on applied thermodynamics. We continue with the reheat cycle developed in chapter 8a, and examine the effect of adding a regenerative heat exchanger in the form of an open feedwater heater, as shown below. I hereby explain the procedure to solve the problem based on reheating rankine cycle turbine in tamil. Steam power cycles a ideal rankine and reheat cycles.
A reheat rankine cycle steams enter the highpressure turbine at 12. One approach to solving cycle problems of this nature is to work your way around the cycle until you have evaluated all the properties to complete the table shown above. Modulating hot gas reheat occupant comfort is uniform and consistent because there are. Just looking at the ts diagram figure 2b for the reheat cycle, it appears that we might be able to raise this mean temperature by allowing the fluid to leave the turbine at s5 at a higher pressure. A gas turbine power plant operates on a simple brayton cycle with air as the working fluid. Class problem reheatregenerative rankine cycle with open and closed feedwater heaters consider a steam power plant that operates on an ideal reheatregenerative rankine cycle with one open feedwater heater, one closed feedwater heater, and.
Gas power cycles our study of gas power cycles will involve the study of those heat engines in which the working fluid remains in the gaseous state throughout the cycle. Thus, the thermal efficiency of the cycle can be determined from. In this example the hp turbine expands the steam from 15 mpa to 1 mpa, and the steam is subsequently reheated back to 600c before being expanded in the lp turbine to 10 kpa. Assume the steam is reheated to the same temperature as in inlet of the highpressure turbine. It is then reheated to 400c and expands to 10 kpa in the lowpressure turbine. Some steam is extracted at this pressure to heat the feedwater in. Precise control with modulating hot gas reheat the humidity control solution. An ideal reheat regenerative rankine cycle with an open feedwater heater has the boiler pressure at 10 mpa, the condenser pressure at 15 kpa, the reheater pressure at 1 mpa, and the. A steam power plant operates on an ideal reheat rankine. This means that the pump and turbine operate isentropically and that the condenser effluent. T he study of indoor air quality has pointed to moisture as one of the main causes of poor indoor air quality.
How does the reheat cycle improve the efficiency of the. Were helping businesses of all sizes convert from fossil fuel to sustainable, lowcarbon biomass heat and power systems. The reheat process brings the states at the lower pressure further out in the superheated vapor region and thus raises the quality if twophase in the last turbine section. Me 201 thermodynamics cycle practice problem solutions.
Pdf power plant lecture notes chapter2 steam power. The steam exits from the turbine will be 100% saturated vapor as shown. Let assume the rankine cycle, which is the one of most common thermodynamic cycles in thermal power plants. Heat is rejected to the surroundings at a rate of 6800 kw, and air flows through the cycle at a rate of 20 kgs. Rankine cycle problems and solutions file,download rankine cycle problems and solutions file,free download rankine cycle problems and solutions file,rankine cycle problems and solutions file pdf ebooks, read rankine cycle problems and solutions file pdf. Ideal reheat rankine cycle efficiencysample calculation steam. In other words, modify the simple ideal rankine cycle with reheat process. Mechanical engineering thermodynamics lec 21, pt 3 of 5.
Determine the fraction of steam extracted from the turbine and the thermal efficiency of the cycle. Pdf power plant lecture notes chapter2 steam power plant. In this case assume a helium gas turbine with single compressor and single turbine arrangement. Draw the enthalpyentropy diagram for reheat rankine cycle as in figure 2. Rankine cycle problems and solutions file,download rankine cycle problems and solutions file,free download rankine cycle problems and solutions file,rankine cycle problems and solutions file pdf ebooks, read rankine cycle problems and solutions file pdf books. The key is that the cycle is an ideal rankine cycle. The steam at the highpressure turbine inlet is at 1500 psia and 800 o f and the effluent is saturated vapor. Brayton cycle reading problems 98 910 978, 984, 9108 open cycle gas turbine engines after compression, air enters a combustion chamber into which fuel is injected the resulting products of combustion expand and drive the turbine combustion products are discharged to the atmosphere. While at first glance this appears to be an attractive cycle a thermal efficiency of 40% is quite good, it has two problems considered as a practical device. Steam is reheated to a final temperature of 550 o c.
The rankine cycle is the fundamental operating cycle of all power plants where an operating fluid is continuously evaporated and condensed. Thermodynamics questions and answers mean temperature of heat addition and reheat cycle. Feb 25, 20 tutorial questions reheat rankine cycle 1. Rankine cycle and its variations are used in steam power plants, marine applications etc. State 6 is saturated mixture with a pressure of 10 kpa. Conceptstudy guide problems 112 rankine cycles, power plants simple cycles 32 reheat cycles 3338 open feedwater heaters 3948 closed feedwater heaters 4956 nonideal cycles 5768 cogeneration 6974. Chapter 9 gas power cycles universiti tenaga nasional. In this case the turbine operates at steady state with inlet conditions of 6 mpa, t 275. Answer to reheat cyclesconsider an ideal steam reheat cycle where steam enters the highpressure turbine. Construct plots of the net power output of the cycle and the thermodynamic efficiency as functions of the operating pressure of the condenser. The air enters the turbine at 1 mpa and k and leaves at 125 kpa, 610 k. Then, you can go back and apply the 1st law to each process in the cycle to evaluate q and w s as need. Exercise 1consider a steam power plant operating on the ideal rankine cycle. Brayton cycle reading problems 98 910 978, 984, 9108 open cycle gas turbine engines after compression, air enters a combustion chamber into which fuel is injected the resulting products of combustion expand and drive the turbine combustion products are discharged to the atmosphere compressor power requirements vary from 4080% of the power output of the turbine re.
View homework help chapter 9 rankine cycle problems solutions. What is difference between ideal rankine cycle and reheat. The steam power plant operates on an ideal reheatregenerative rankine cycle with one open feedwater heater, one closed feedwater heater, and one reheater, as shown in the diagram. High humidity can cause many problems including mold growth, condensation, wood rot, paper deterioration, increase in sickness and allergic reactions. Problems designated by a c are concept questions, and students are encouraged to answer them all. The processes of reheat rankine cycle are explained below using the enthalpyentropy diagram. Solved problem based on reheating rankine cycle m 3.
Power plant lecture notes chapter2 steam power plant cycles. Reheating is a practical solution to the excessive moisture problem in turbines, and it is commonly used in modern. Let assume the closed brayton cycle, which is the one of most common thermodynamic cycles that can be found in modern gas turbine engines. The assumptions made in the solution of this problem cannot be verified with the given. C1 ideal reheat rankine cycle consider a steam power plant operating on the ideal reheat rankine cycle. Rankine cycle problems and solutions file keywords. Figure 3 shows a sensitivity analysis that confirms the benefit of a higher reheat pressure for improving cycle efficiency. An ideal reheatregenerative rankine cycle with an open feedwater heater has the boiler pressure at 10 mpa, the condenser pressure at 15 kpa, the reheater pressure at 1 mpa, and the. A reheat rankine cycle using water as the working fluid operates between the pressure limits of 7. The fractions of steam extracted are determined from the mass and energy balances of the feedwater.
One of key parameters of such engines is the maximum turbine inlet temperature and the compressor pressure ratio pr p. Aaon has addressed all of these humidity control problems with a unique design incorporating a reheat coil, a modulating 3way hot gas reheat valve, supply air temperature sensor, and a simple controller. Consider condenser pressures from 10 kpa to 200 kpa data. Which are better for you, better for business and better for the planet. Problems and solutions, chapter9 engineering thermodynamics. Apr 26, 2019 rankine cycle solved example support me through phonepe,paytm,tez my number. The reheat in the steam power cycle allows to improve its efficiency because any method causing a growth of an area of particular cycle is directly related to the obtainable work. A steam power plant operates on an ideal reheat rankine cycle between the pressure limits of 15 mpa and 10 kpa. Calculate the cycle thermal efficiency and the moisture content of the steam leaving the lowpressure turbine. Example 1 superheat rankine cycle qin 2 3 wout boiler turbine consider the same rankine power cycle as we analyzed before. Water is the working fluid in an ideal rankine cycle with reheat. Various items for this system per unit of mass flow rate through the boiler are to be determined.
We will find that this system does result in an increase in thermal efficiency by preheating the. An ideal reheat rankine cycle with water as the working fluid operates the boiler at 15,000 kpa, the reheater at 2000 kpa, and the condenser at 100 kpa. In this case assume a simple cycle without reheat and without with condensing steam turbine running on saturated steam dry steam. Pump in reheat rankine cycle, there are essentially two turbines, one is high pressure turbine hpt and the other is low pressure turbinelpt. Highpressure liquid enters the boiler from the feed pump 12 and is heated to the saturation temperature 2. Given a rankine cycle with reheat operating with the following conditions. But this time we are going to superheat the steam in the boiler before allowing it to enter the turbine at 6 mpa. Ideal reheat rankine cycle efficiencysample calculation free download as. Reheat cyclesconsider an ideal steam reheat cycle where. Steam power cycle example problem with complete solution. The topping cycle is a gasturbine cycle and the bottoming cycle is a nonideal reheat rankine cycle. Tutorial questions reheat rankine cycle linkedin slideshare. Problems with the are solved using ees, and complete solutions together with parametric studies are included on the enclosed dvd.
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