You add heat and pressure is kept constant, i.e. volume increases. That is usually the physical process that results in work being done. But here most of the heat goes into vaporization/condensation. Is this why we say that there is no work done during these processes?Nidum said:In these processes heat is just being added or removed at constant pressure . Where is there any physical activity that results in work being done ?
The purpose of heat injection and work during a Rankine cycle is to convert thermal energy into mechanical work. This process is essential in many power plants and engines, as it allows for the production of electricity or mechanical motion.
Heat injection occurs in the boiler, where high-pressure liquid water is heated to its boiling point, converting it into high-pressure steam. The steam then expands through the turbine, producing mechanical work. The remaining steam is condensed back into liquid form in the condenser, releasing heat energy, and the cycle repeats.
The amount of heat injection and work during a Rankine cycle is affected by the pressure and temperature of the heat source, the efficiency of the turbine, and the efficiency of the condenser. Additionally, the type of working fluid used in the cycle can also impact the amount of heat injection and work.
One of the main advantages of using a Rankine cycle is its versatility, as it can use a variety of heat sources, such as coal, natural gas, or nuclear fuel. Additionally, the cycle is relatively simple and has a high efficiency, making it a cost-effective method of power generation.
One limitation of the Rankine cycle is its low thermal efficiency compared to other power generation methods, such as combined cycle systems. It also requires a large amount of water for the condensation process, which can be a limitation in areas with water scarcity.