Task 2: Explain Carnot and Rankine steam power cycle and also describe improvements to the Rankine cycle and draw the plant cycle of steam plant with the following features:
i. Boiler ii. High pressure turbine. iii. Low pressure turbine. iv. Condenser.
v. Direct contact feed heaters fed from the L.P. turbine. vi. Direct contact feed heaters fed from the H.P. turbine. vii. Hot well. viii. High pressure feed pump. ix. Low pressure feed pump.
x. Extraction pump.
The Rankine cycle is used to anticipate the performance of steam turbine systems, in theory it can also be used for reciprocating engines such as steam engines. It regards to thermodynamic cycle of a heat engine which converts heat energy into mechanical energy. The heat…show more content… Process 3-4:
The dry saturated vapour expands in the turbine hence generating power. Due to this the temperature and pressure of vapour is reduced and sum amount condensation can occur.
Then the wet vapour enters a condenser, it is turned into saturated liquid after being condensed in constant pressure. Carnot cycle
The Carnot cycle was proposed by French physicist Sadi Carnot in 1824. Carnot cycle can be used to find the upper limit on the efficiency of thermodynamic engine which can be achieved during the working of conversion from heat into work or inversely. the Carnot cycle consist of four process as show in figure they are: 1. 1-2: in this process the gas expands but it does not work on the surrounding. The temperature of the gases stays steady in this procedure subsequently the development is isothermal. The heat energy from the high temperature reservoir drives the development of the gases and this outcome in the expansion of entropy of the…show more content… The expansion of the gases continues hence the work is done on the surroundings, and losing an amount of internal energy equal to the work that leaves the system.
3. 3-4: in this process the surroundings does work on the gas, due to this there amount of energy leaves the system to the low temperature reservoir and the entropy of the system decreases.
4. 4-1: it is assumed that the engine mechanisms is thermally insulated, and frictionless. The surroundings do work on the gas, due to this the internal energy increases and compressing it. Hence the temperature rises from T1 due to the work added to the system. In this step the gases stay in same state as in the start of step 1.
Diagram of steam power plant