The efficiency of a steam turbine is just the ratio of power out to power in, but if you want to be able to calculate it from the basic mechanical design, this is a specialised topic. In the link below is a general description of steam turbines, in the references and additional reading list there are some references that may help you.
Station heat rate = Specific fuel consumption * Calorific value of fuel
Turbine heat rate = (Main steam flow * Main steam enthalpy + Aux Steam flow * Aux steam enthalpy - Feed water flow * Feed water enthalpy + Makeup water flow* Makeup water enthalpy)/Power generation
Unit of Heat rate is kcal/kWh, kJ/kWh,Mcal/MWh, MJ/MWh,
Turbine efficiency = 1/ turbine heat rate for Kcal/KWh is 860/ turbine heat rate
For kJ/kWh is 3600/turbine heat rate
Station efficiency = 1/ station heat rate for Kcal/KWh is 860/ station heat rate
For kJ/kWh is 3600/station heat rate
The steam rate (or heat rate, watering rate) is determined by taking the total heat or steam input and dividing the total KVa output of the generator.
On a reheat turbine the heat input is the steam input at the throttle conditions PLUS the reheat addition from the reheater. The addition is determined by taking the steam heat content at the outlet from the reheater and subtracting the heat content at the inlet to the reheater and adding that difference to the initial throttle heat content. On an induction stage if fresh steam is admitted from a secondary source this must be added to the total, and on a bleeder turbine the extraction steam conditions must be subtracted from the entirety. The total heat content entering the machine is then written as a comparative to the initial steam condition at the throttle to get the "true" steam rate of the turbine, in lbs of steam per KVa.
manish
Turbine cycle heat rate is a measure of the turbine efficiency. It is determined from the total energy input supplied to the turbine divided by the electrical energy output. The energy input is the difference between the energy in the steam supplied to, and leaving from the turbine. The total energy supplied is the sum of the steam mass flow rates to the turbine multiplied by their respective enthalpies. The energy leaving is the sum of mass flow rates exiting the turbine multiplied by their respective enthalpies. Take the difference in the total energy supplied and leaving, divide by the electrical output and this gives you heat rate, typically expressed in Btu/kWh or kJ/kWh. This is easy for a single source of steam passing through the turbine to a condenser, but gets a bit more tricky for reheat turbines with multiple extractions as all the streams in and out have to be accounted for.
In Boiler follow turbine mode , Boiler produces a constant pressure behind throttling valve and throttling valve adjusts necessary pressure and required steam as High Pressure steam for entering the turbine . In Valves Wide Open (VWO) mode the efficiency is maximum and we haven't any loss. (It's nearly 106% Turbine MCR) . In Turbine MCR , we have a little loss and consequently a little bit worse heat rate . In partial load , loss is more and efficiency worse.
there are stages, fixed blades on the turbine shell and rotating blades on the rotor. They are very close together sooo, because the steam enters at one end of the turbine it heats that area first and it expands the metal there faster than at the other end causing it to rub. if you heat it slowly the turbine casing and the rotor grow at ~ the same rate so the stages don't rub together. If you heat too quickly,by just admitting a high volume of steam, the rotor heats up to fast, because of it has less metal to heat up, it rubs the fixed blades. this is called going long (the rotor is longer than the tolerances between the fixed blades on the casing)
212 degrees Fahrenheit
manish
Efficiency formula for a steam turbine is typically derived by dividing the electrical power output by the heat energy input. The heat rate of the steam turbine represents the amount of heat energy required per unit of electrical power generated, and by rearranging the equation, we can derive the efficiency formula as the reciprocal of the heat rate.
Steam Rate calculation Formula for Steam Turbine
Divide heat added to the boiler between feedwater inlet and steam outlet by the kilowatt output of the generator at the generator terminals. Rate expressed in btu. See article.
Turbine cycle heat rate is a measure of the turbine efficiency. It is determined from the total energy input supplied to the turbine divided by the electrical energy output. The energy input is the difference between the energy in the steam supplied to, and leaving from the turbine. The total energy supplied is the sum of the steam mass flow rates to the turbine multiplied by their respective enthalpies. The energy leaving is the sum of mass flow rates exiting the turbine multiplied by their respective enthalpies. Take the difference in the total energy supplied and leaving, divide by the electrical output and this gives you heat rate, typically expressed in Btu/kWh or kJ/kWh. This is easy for a single source of steam passing through the turbine to a condenser, but gets a bit more tricky for reheat turbines with multiple extractions as all the streams in and out have to be accounted for.
The heat rate of a gas turbine using petroleum is 13,622. On the other hand, gas turbines that use natural gas produce a heat rate of 11,499.
The guaranteed heat rate, indicated on performance data table of power plant is calculated in accordance with the following formula: HR = (Qms x Hms - Qfw x Hfw + Qhrh x Hhrh - Qcrh x Hcrh - Qas x Has + Qmu x Hmu) x 3600 / W HR = heat rate [kJ/kWh] W = gross power output [kW] Q = mass flow [kg/s] H = enthalpy [kJ/kg] Subscript: ms = main steam fw = boiler feedwater hrh = hot reheat steam crh = cold reheat steam as = auxiliary steam extraction from turbine cycle for boiler users mu = make up water at condenser
The efficiency of a steam turbine is just the ratio of power out to power in, but if you want to be able to calculate it from the basic mechanical design, this is a specialised topic. In the link below is a general description of steam turbines, in the references and additional reading list there are some references that may help you.
In Boiler follow turbine mode , Boiler produces a constant pressure behind throttling valve and throttling valve adjusts necessary pressure and required steam as High Pressure steam for entering the turbine . In Valves Wide Open (VWO) mode the efficiency is maximum and we haven't any loss. (It's nearly 106% Turbine MCR) . In Turbine MCR , we have a little loss and consequently a little bit worse heat rate . In partial load , loss is more and efficiency worse.
there are stages, fixed blades on the turbine shell and rotating blades on the rotor. They are very close together sooo, because the steam enters at one end of the turbine it heats that area first and it expands the metal there faster than at the other end causing it to rub. if you heat it slowly the turbine casing and the rotor grow at ~ the same rate so the stages don't rub together. If you heat too quickly,by just admitting a high volume of steam, the rotor heats up to fast, because of it has less metal to heat up, it rubs the fixed blades. this is called going long (the rotor is longer than the tolerances between the fixed blades on the casing)
Vacuum dropping in a steam turbine can be caused by air leakage into the system, inadequate steam supply, malfunctioning condenser or cooling system, or excessive steam flow rate. This drop in vacuum can reduce the efficiency of the turbine and impact its performance. Regular monitoring and maintenance of the system are essential to prevent issues leading to vacuum drop.
Steam (under pressure) comes into contact with the blades of the turbine through which it is flowing and, by the direct application of force, causes the blades to move, turning the turbine shaft. The turbine coverts the thermal energy of the steam into (rotating) mechanical energy. Surf on over to our friends at Wikipedia using the provided link and get more info. Oh, and check out the pics! Answer it depends what type of turbine one is using types of steam turbine 1 impulse turbine 2 reaction turbine in 1 st one steam is completely expanded inside nozzle and all pressure energy get converted in to kinetic energy using this impulse force turbine runs. in 2nd steam is multiple stage blades are used where high pressure superheated steam gets expanded inside the turbine in each stage and after each stage velocity of steam increases. very high temperature superheated steam is reaquired because it has very high specific volume which helps in reducing mass flow rate of steam.