Table of Contents
- 1 Why pump work is neglected in Rankine cycle?
- 2 Which pump is used in Rankine cycle?
- 3 What is the function of the feed water pump of a boiler?
- 4 What is reverse Rankine cycle?
- 5 What is the purpose of feed pump?
- 6 How does the efficiency of a pump affect a turbine?
- 7 How does an inefficient pump affect the boiler?
Why pump work is neglected in Rankine cycle?
The pressure of the condensate is raised in the feed pump. Because of the low specific volume of liquids, the pump work is relatively small and often neglected in thermodynamic calculations.
What is the purpose of pump in Rankine cycle?
The Rankine cycle system consists of a pump, boiler, turbine, and condenser. The pump delivers liquid water to the boiler. The boiler heated by the solar heat converts water to superheated steam. This steam is used to run the turbine which powers the generator.
Which pump is used in Rankine cycle?
The present paper focuses on the comparative experimental operating characteristics of working fluid pumps used in the organic Rankine cycle (ORC) system with R245fa, including multistage centrifugal pump, hydraulic diaphragm metering pump, and roto-jet pump.
What is the relation between the pump work in Rankine cycle?
During a Rankine cycle, the pumps’ work is done on the fluid between states 1 and 2 (isentropic compression). Work is done by the fluid in the turbine between stages 3 and 4 (isentropic expansion).
What is the function of the feed water pump of a boiler?
Boiler Feed Pumps are designed to handle the amount of pressure your operation needs. Boiler feedwater pumps transport water into boilers using high pressure. Thus, a boiler feed pump is built to handle extremely high water pressure to deliver the feedwater into the boiler system.
What is the effect of lowering the condenser pressure on pump work input?
Lowering the condenser pressure results in increasing the area of the TS diagram, hence improves the net work output of the cycle and improves the thermal efficiency of the cycle.
What is reverse Rankine cycle?
An ideal thermodynamic cycle consisting of heat addition at constant pressure, isentropic expansion, heat rejection at constant pressure, and isentropic compression; used as an ideal standard for the performance of heat-engine and heat-pump installations operating with a condensable vapor as the working fluid, such as …
How can you increase the efficiency of a Rankine cycle?
Increasing the Efficiency of Rankine Cycle That is, to increase the efficiency one should increase the average temperature at which heat is transferred to the working fluid in the boiler, and/or decrease the average temperature at which heat is rejected from the working fluid in the condenser.
What is the purpose of feed pump?
A feed pump is a type of pump that supplies water to a boiler to produce steam. For industrial purposes, a feed pump supplies a liquid for further processing. These pumps are high-pressure pumps and are generally of two types: Positive displacement type feed pumps.
How does feed pump work?
The work of a boiler feed pump is to discharge the condensate boiler feed water from hotwell to the boiler drum. With the rotation of shaft and impeller the hot feed water is thrown outwards radially across the walls of the pump; along the path of the flow. This increase the speed of the fluid so does the pressure.
How does the efficiency of a pump affect a turbine?
The turbine efficiency directly reduces the work produced in the turbine and, therefore the overall efficiency. The inefficiency of the pump increases the enthalpy of the liquid leaving the pump and, therefore, reduces the amount of energy required to evaporate the liquid.
How is work done in the Rankine cycle?
During a Rankine cycle, work is done on the fluid by the pumps between states 1 and 2 (isentropic compression). Work is done by the fluid in the turbine between stages 3 and 4 (isentropic expansion).
How does an inefficient pump affect the boiler?
The inefficiency of the pump increases the enthalpy of the liquid leaving the pump and, therefore, reduces the amount of energy required to evaporate the liquid. However, the energy to drive the pump is usually more expensive than the energy to feed the boiler.
How does cooling water affect the Rankine cycle?
The deposition of dirt in condensers during operation with cooling water reduces the efficiency. The net work produced in the Rankine cycle is represented by the area of the cycle process in Figure 2. Obviously, this area can be increased by increasing the pressure in the boiler and reducing the pressure in the condenser.