Why water is commonly used as the working fluid in power plant?
Availabilty and low cost are the 2 major reasons behind the use of water over other fluids. Power plants are mostly constructed near water sources like river, lakes etc. Water is taken from the rivers directly, cleansed, pumped and converted to steam.
What is the working fluid in steam power plant?
In a simple vapour power plant, the working fluid which is water undergoes a change of phase. Heat is transferred to water in the boiler from an external source to raise steam. The high pressure, high-temperature steam leaving the boiler expands in a turbine to produce shaft work.
What should be the desired properties of a working fluid in a Rankine Cycle?
Accordingly, a working fluid having a higher critical temperature is more preferred for use in a Rankine cycle. Accordingly, the substance having a higher critical temperature has a higher latent heat of vaporization than that of the substance having a lower critical temperature.
What is the working fluid in ocean thermal power plant?
Closed-cycle OTEC uses working fluids that are typically thought of as refrigerants such as ammonia or R-134a. These fluids have low boiling points, and are therefore suitable for powering the system’s generator to generate electricity.
What makes a good working fluid?
The working fluid should possess a low value of the liquid viscosity, a high latent heat of vaporisation, a high liquid thermal conductivity and a good wetting capability. The working fluid should have low vapour and liquid specific volumes. These properties affect the rates of heat transfer in the heat exchangers.
What is ideal working fluid?
The fluid should have high critical temperature so that the saturation pressure at the maximum permissible temperature is relatively low. It should have a large enthalpy of evaporation at that pressure.
What is meant by ideal working fluid?
Why ammonia is used as working fluid in OTEC?
Overall, ammonia is shown to be the best fluid (i.e. it yields the lowest value of A/Wnet), although in some cases only by a small margin. The thermophysical property that gives ammonia its general superiority is its relatively high thermal conductivity.
How does ocean thermal energy work?
Ocean Thermal Energy Conversion (OTEC) systems use a temperature difference (of at least 77° Fahrenheit) to power a turbine to produce electricity. Warm surface water is pumped through an evaporator containing a working fluid. The vaporized fluid drives a turbine/generator.
Which of the following is a good choice of working fluid?
Explanation: CFCs are a good choice for working fluid.
What is the work done on the working fluid of a constant pressure process?
Since the pressure is constant, the force exerted is constant and the work done is given as W=Fd, where F (=PA) is the force on the piston applied by the pressure and d is the displacement of the piston.
What do you mean by working substance or working fluid or working medium?
Definition of working substance : a usually fluid substance that through changes of temperature, volume, and pressure is the means of carrying out thermodynamic processes or cycles (as in a heat engine)