Why is steam turbine exhaust temperature high?
Why is steam turbine exhaust temperature high?
The long-term plant HP turbine expands recycle steam at 650°C and 350 bar. Both the IHP turbine and the IP turbine produce very high temperature exhaust stream requiring high temperature piping designs. The IP expansion stream is cooled in the HRSG to about 240°C before expansion in the LP turbine.
What is exhaust pressure in steam turbine?
Exhaust pressure at the exit of the last-stage blades is one of the most important parameters that limit the operation of a steam turbine, especially on days with hot ambient conditions. Last-stage blades are generally highly stressed and are vulnerable to vibrations caused by aeromechanics instabilities.
What is that temperature called to which the exhaust gases of a gas turbine are cooled to?
9. What is that temperature called to which the exhaust gases of a gas turbine are cooled? Explanation: As the maximum temperature of cooling that can be reached has to be the dewpoint of one of these gases, so the dewpoint of Sulphuric Acid [Sulphur dioxide discharge] is chosen.
What is back pressure of turbine?
Back Pressure Turbines: a type of steam turbine that is used in connection with industrial processes where there is a need for low or medium pressure steam. The high pressure steam enters the back pressure steam turbine and while the steam expands – part of its thermal energy is converted into mechanical energy.
What is the degree of reaction for a Parsons turbine?
A very widely used design has half degree of reaction or 50% reaction and this is known as Parson’s Turbine. This consists of symmetrical stator and rotor blades.
Is diesel exhaust hotter than gas exhaust?
In contrast, the heavy molecular structure of diesel fuel requires more heat to trigger combustion within the engine chamber. As a result, the exhaust temperatures emitted are particularly higher than gasoline, ranging from 1,000 to 1,200 degrees Fahrenheit.
What is the highest recommended pyrometer temperature?
It depends on where the pyrometer is sensing. If you install pre-turbo then your safe point is a maximum of 1200 F or so, (it doesn’t vary between engines much as it’s based on the melting point of the aluminum pistons).
Why is turbine speed constant?
This is because the shaft in which the turbine and generator or alternator fixed rotates at a constant speed. Because of a balance between the resistance torque giving by the electrical load and the driving torque depending upon the change of the angular momentum of the fluid flowing through the turbine clear.
Is there a minimum exhaust temperature for a steam turbine?
General replay, there is no single value for a minimum acceptable exhaust temperature. Steam temperature, pressure and flow rate are all very much related. So, even the manufacturer has to know the rest of the parameters in you operating case/mode to tell you the acceptable exhaust temperature.
What happens if the exhaust temperature of a gas turbine is low?
A simple layout of the air–steam combined cycle power plant (CCPP). If gas turbine exhaust temperature is lower than the value for peak exergetic capture of exhaust exergy to steam exergy in Fig. 4.6, the cycle can be improved by adding one or more additional steam generation pressures.
What’s the back pressure on a steam turbine?
The back pressure on the steam turbine can be lowered from 1.013 to 0.1bar abs. Condenser is mainly used to convert the low pressure steam at the end of the turbine to liquid so that the process is continued.
How is the temperature of the exhaust gas measured?
For an accurate measurement of exhaust heat, use can be made of an exhaust calorimeter. This is a gas-to-water heat exchanger in which the exhaust gas is cooled to a moderate temperature and the heat content measured from observation of cooling water flow rate and temperature rise.