What is reheat in steam power plant?
Reheating increases the efficiency by raising the mean temperature of the heat addition process, by increasing the steam temperature at the turbine inlet and also by increasing the efficiency of the expansion process in the steam turbine.
What is the effect of reheating on Rankine cycle?
The Rankine cycle performance and efficiency can be improved with the reheat cycle as well as by regenerative cycle. It can be improved by increasing the thermodynamic properties of the steam entering into the turbine. At the initial stage, increased pressure results in increased expansion ratio.
What is reheat and regeneration in Rankine cycle?
Reheating of steam improved the thermal efficiency of the plant, net work output of turbine, reduction in blade erosion (or quality of steam improve). By regeneration thermal efficiency of the plant can be increased but it does not affect work output from turbine.
What is the purpose of reheat cycle Mcq?
The main advantage of the reheat cycle is that it increases the dryness fractions of steam at condenser inlet thus making it possible to use higher boiler pressure. It also increases the net-work output thus decreasing the mass flow rate of steam required for the same power output.
How does a reheat cycle increase output efficiency in steam power cycle?
In case of two reheats, steam is super-heated twice at different constant temperatures. A high reheat pressure increases the the moisture content at turbine exhaust which results in scaling and it should be optimised. Thus the work produced is increased ,thereby efficiency increases.
What are the effects of reheating and regenerating on the efficiency of power cycles?
Abstract. Reheating in a reheat regenerative steam power cycle increases efficiency by increasing the average temperature of heat reception, but also increases the irreversibility of feed water heaters by raising the temperature of the superheated steam used for the regenerative process.
What is reheat regenerative cycle?
Introduction: To increase the thermal efficiency a reheat cycle is combined with a regenerative cycle. The regenerative cycle encounters a problem with water droplets at the low pressure side of the turbines.
What is the effect of reheat on the network output of the steam power plant?
Explanation: With reheat, the area under the curve increases in comparison to what it was without reheat. Hence, Net Work output of the plant increases.
What is the use of reheat cycle in steam turbine Mcq?
What is the use of reheat cycle in steam turbines? Explanation: Reheat cycle is worked with rankine cycle to remove the moisture from the steam.
What is the thermodynamic analysis of a Rankine cycle reheat steam power plant?
Learn more. In this study, a thermodynamic analysis of a Rankine cycle reheat steam power plant is conducted, in terms of the first law of thermodynamic analysis (i.e. energy analysis) and the second law analysis (i.e. exergy analysis), using a spreadsheet calculation technique.
Can more than one reheat process be used in a steam power plant?
More reheat processes can be used but, due to the added cost and complexity to modify the cycle, it not practical to use more than two reheat processes. A steam power plant operates on the ideal reheat Rankine cycle. Steam enters the high-pressure turbine at 8 MPa and 500°C and leaves at 3 MPa.
How to increase the efficiency of Rankine cycle?
One of the problems in increasing the efficiency of the ideal Rankine cycle is moisture content of the steam at the final stages of the expansion. A two stage turbine with reheat in between, is the solution to the excessive moisture problem in turbines and, is commonly used in actual steam power plants.
How does a steam power plant work?
A steam power plant operates on the ideal reheat Rankine cycle. Steam enters the high-pressure turbine at 8 MPa and 500°C and leaves at 3 MPa. Steam is then reheated at constant pressure to 500°C before it expands to 20 kPa in the low-pressure turbine. Determine the turbine work output, in kJ/kg, and the thermal efficiency of the cycle.