168 w1a0352 intern ppt
- 2. BHEL is an integrated power plant equipment manufacturer and one of the largest engineering and manufacturing companies of its kind in India. The company is engaged in the design, engineering, manufacture, construction, testing, commissioning and servicing of a wide range of products and services for the core sectors of the economy, viz. Power, Transmission, Industry, Transportation, Renewable Energy, Oil & Gas and Defence with over 180 products offerings to meet the needs of these sectors. Supplies steam turbines, generators, boilers and its auxiliaries up to 1000 MW. Supplies hydro turbines and generators of up to 250MW. Has proven expertise in plant performance improvement through renovation, modernization and up rating of a variety of power plant equipment
- 3. In the era of Mechanical Engineering, Turbine, A Prime Mover (Which uses the Raw Energy of a substance and converts it to Mechanical Energy) is a well-known Machine most useful in the field of Power Generation. This Mechanical energy is used in running an Electric Generator which is directly coupled to the shaft of turbine. From this Electric Generator, we get electric Power which can be transmitted over long distances by means of transmission lines and transmission towers. In my Industrial Training in B.H.E.L., HYDERABAD I go through all sections in Turbine Manufacturing. First management team told me about the history of industry, Area, Capacity, Machines installed & Facilities in the Industry. After that they told about the gas Turbine its types, parts like Blades, Casing, Rotor etc. Then they told full explanation of constructional features and procedure along with equipment used. They told about the safety precautions, Step by Step arrangement of machines in the block with a well-defined proper format. They also told the material of blade for a particular desire, types of Blades, Operations performed on Blades.
- 4. Gas turbines are common power generators which are used mainly in power generation systems and propulsion systems. Most of the gas turbines are internal combustion machines while the rest are fired externally. The sizes of gas turbines can vary from 500kW to 250MW according to their applications. A typical gas turbine mainly consists of three components namely compressor combustion chamber turbine
- 7. The Brayton or the Joule cycle is commonly used to analyse the gas turbine systems and the figure shows a Temperature-Entropy (TS) diagram representation of an ideal Brayton cycle. In figure 2, from point 1 to point 2 the air is isentropically compressed and the heat is supplied at constant pressure from point 2 to point 3. Finally, the air is isentropically expanded from point 3 to point 4.
- 8. An aircraft turbine engine is the most widely used propulsion system in the aviation industry. Turbine engines come in several types, each with its own requirements for maintenance and aircraft engine overhaul. That’s why it is important to choose the right company when performing repairs and maintenance on your aircraft turbine engine. Turbojet- A turbojet is the simplest of all aircraft turbine engines, consisting of four sections: compressor, combustion chamber, turbine section and exhaust. In this type of engine, air is passed at a high rate of speed into the combustion chamber where the fuel inlet and igniter is located. The turbine, driven by expanding air, causes thrust from accelerated exhaust gases. Covington Aircraft has extensive experience in aircraft engine overhaul, as well as routine maintenance for these types of engines.
- 9. Turbo fan- Merging the best features of the turbojet and turboprop, the turbofan is an aircraft turbine engine that diverts a secondary flow of air around the combustion chamber, which creates additional thrust. This is the most modern version of an aircraft turbine engine and the one often found on high-speed transport and fighter planes. Because many corporations choose turbofan engines, Covington Aircraft focuses on plane maintenance to keep corporate planes in the air, avoiding grounded aircraft due to maintenance issues. Turboprop- Turboprop engines drive propellers through a reduction gear, which provides optimum propeller performance at slower rpm speeds. That translates to greater fuel efficiency and performance at slower airspeeds, which is why turboprops are popular aircraft turbine engines for small, commuter aircraft, cargo planes and agricultural use. The propellers are less efficient as the aircraft speed increases, making them better for planes that do not have travel at higher speeds.
- 10. The stationary nozzle guide vanes are positioned in a ring with convergent spaces between each vane. As the gas passes through the vanes it is accelerated and directed at the correct angle onto the moving turbine rotor blades. There are three types of turbine rotor blade. The three types are: 1.impulse blades 2. reaction blades 3.impulse/reaction blades
- 11. With this type of rotor blade the gas pressure drop occurs in the stationary nozzle guide vanes. The converging space between the guide vanes causes the gas to accelerate so gaining in kinetic energy and losing pressure energy and temperature.
- 12. With this type of rotor blade the stationary nozzle guide vanes would simply redirect the gas onto the blades by giving it a whirling motion. There would be no acceleration or loss of pressure in the nozzle guide vanes. The turbine rotor blades are aerofoil shaped and their inter-blade spaces are convergent.
- 13. Aircraft main engines use a combination of impulse and reaction sections in one rotor blade. The mix is about half impulse and half reaction. At half span the section is impulse at the leading edge changing to reaction towards the trailing edge, (about 50% impulse and 50% reaction).
- 14. ISO ambient conditions for the industrial gas turbine are described as follows: Ambient temperature - 150C/590F Relative humidity- 60 % Ambient pressure - 1.013 bar/14.7 psi Ambient temperature Increases in the ambient temperature can highly affect the gas turbine performance. When the inlet air is hot the net power of the gas turbine reduces. For every 1 0C increment in the ambient temperature the amount of the reduction in power output is nearly 0.9%. For an increment of the ambient temperature by one Kelvin above the ISO condition, the reduction of the gas turbine thermal efficiency is nearly 0.1%.
- 15. Ambient Pressure Ambient pressure is a site dependent parameter and it changes with the elevation. With the increases of the elevation, the density of the air reduces, thus ambient pressure reduces. As results of that mass flow rate, fuel rate and the power output of the gas turbine reduce nearly by 3.5% for each 1000 feet (305m) of elevation above the sea level .
- 16. Humidity The humid air has less density than the dry air. As a result of low-density air, the amount of dry air mass entering into the gas turbine reduces. Thus, the performance of the gas turbine reduces.
- 17. Pressure ratio The amount of compressibility of the compressor can be considered as the pressure ratio. the efficiency of the open ideal gas turbine cycle can be derived as: 𝜼 = 𝑵𝒆𝒕𝒘𝒐𝒓𝒌𝒐𝒖𝒕𝒑𝒖𝒕/𝑯𝒆𝒂𝒕𝒔𝒖𝒑𝒑𝒍𝒊𝒆𝒅 = (𝑪𝒑 (𝑻𝟑– 𝑻𝟒) − 𝑪𝒑 (𝑻𝟐 – 𝑻𝟏) )/𝑪𝒑 (𝑻𝟑 – 𝑻𝟐) From the isentropic temperature and pressure relation : 𝑻𝟐/𝑻𝟏= (𝑷𝟐/𝑷𝟏)(𝜸−𝟏)/𝜸 The efficiency can be shown in term of pressure ratio 𝜼 = 𝟏− (𝟏/𝒓)(𝜸−𝟏)/𝜸)
- 18. According to the above relation the efficiency of the gas turbine depends only on the pressure ratio and gamma (𝛾). The efficiency of the gas turbine increases with the pressure ratio.
- 19. Turbine inlet temperature- Turbine inlet temperature (TIT) can be defined as the temperature of the air gas mixture at the inlet of the gas turbine and it is one of the most critical parameters which influences the gas turbine performance. Both the power output and the thermal efficiency can be improved by increasing the TIT.
- 20. Isentropic efficiency- An isentropic process is a constant entropy process and it can be proved that any adiabatic and reversible process is an isentropic process. An adiabatic process is one in which no heat is transferred to or from the fluid during the process while in the reversible process, both the fluid and its surroundings can always be restored to their original state), but in reality it is hard to find any reversible process due to losses in the fluid flow path. Figure represents T-S diagram for the compression and the expansion of the gas turbine. The process 1 to 2S in figure 10 represents isentropic compression while process 1 to 2 represents an actual compression. For the expansion case in figure10 the process 3 to 4S indicates the isentropic expansion while the process 3 to 4 represents the actual expansion.
- 22. This report deals with the manufacturing of gas turbine mainly rotors in bhel hyderabad and also discuss about the working principle of power plant and theoretical background of gas turbines and it discusses about the various components of gas turbines
- 23. THANK YOU