Normally the high pressure and intermediate pressure stages of a steam turbine are of the impulse type. Temperature control is important for preventing excessive temperature in the turbine. Power pdf is flexible enough to serve any industry, yet powerful enough to edit any document. Fan shaft power or brake horsepower depending upon the fan static efficiency, one can calculate whether the fan system will deliver the appropriate amount of air. Steam turbines are machines that are used to generate mechanical rotational motion power from the pressure energy of steam. The reason lies in relatively low steam temperature 6 mpa.
The graduation of gas turbine based engines to jet engines in all its variants comes from the basic fact. Unit 1 introduction to power plants introduction to. If the air were not removed from the system it could cause corrosion problems in the boiler. The variation in load during the operation of a steam turbine can have a significant impact on its performance. Growth decelerated for all regions and for all fuels. Introduction in september 2015, the commission cleared the acquisition of the thermal power, renewable power and grid businesses of. The water passes through the plant without greatly changing the flow rate of the river. Unlike with reciprocating engines, for instance, compression, heating and expansion are continuous and. A typical turbine governing system has two unloaders one activated by low condenservacuum. In 1924 krupp built the steam turbine locomotive t18 001, operational in. As a global technology leader in the design and manufacturing of plate heat exchangers, our product range is one of the most extensive on the market. Steam consumption of steam turbine is depending to required output power and efficiency of the turbine. Partitions between pressure stages in a turbines casing are called diaphragms.
Two types of modern steam turbines and their mechanical. Oil remains the worlds leading fuel, accounting for 33. How an air ejector works in a boiler feed system steam. Steam turbines power generation siemens global website.
In addition, there are some losses of energy due to wetness of steam where the water particles are dragged along with steam at the expense of some kinetic. A heat engine is a device which transforms the chemical energy of a fuel into thermal energy. Beyond the turbine end of the gas generator is a freely rotating turbine. Impulse and reaction principles, compounding, velocity diagrams for simple and multistage turbines, speed regulationsgovernors and nozzle governors. Introduction to power plants run of the river in some areas of the world, the flow rate and elevation drops of the water are consistent enough that hydroelectric plants can be built directly in the river. Turbine is a rotary engine that converts the energy of a moving stream of water, steam, or gas into mechanical energy. Maintenance and overhaul of steam turbines wgp42 05. Operation and maintenance schedule of a steam turbine. There are no standby losses in the gas turbine power plant whereas in steam power plant these losses occur because the boiler is kept in operation even when the turbine is not supplying any load. Steam turbine governing is the procedure of controlling the flow rate of steam to a steam turbine so as to maintain its speed of rotation as constant. Power requirements total fan power can be calculated using the aforementioned information and assuming nominal gear box efficiencies of 97% and motor efficiencies 9294%. In the steam engine or a steam turbine plant, the heat of combustion is employed to generate. Steam turbines are the most popular power generating devices used in the power plant industry primarily because of the high availability of water, moderate boiling point, cheap nature and mild reacting properties.
Boiler, turbine, condenser, pump, carnot cycle for steam, disadvantages of carnot cycle application. Moisture content of more than 10% will cause excessive erosion on the turbine blades. The heat of steam is converted to mechanical energy in the steam turbine and then to electrical energy in the generator. Fundamentals of fluid mechanics chapter 12 pumps and turbines. Be it power generation plants, district heating, biomass, wasteto energy, seawater desalination or solar heat. Now, let this turbine be made up of parsons stages, for which the velocity triangles are symmetrical. Let this be the entry velocity of steam in a given stage refer to comment no. Choose a convenient speed and a diameter of the rotor, so that the velocities of.
In addition to gasketed, brazed, and fullywelded plate heat exchangers, our product spectrum also includes a range of unique processoptimized models with special functions. Competition merger brief 12016 article 1 competition merger brief general electric alstom. In its simplest form, a steam turbine consist of a boiler steam generator, turbine, condenser, feed pump and a variety of auxiliary devices. Typical air cooled condenser steam distribution manifold air cooled condenser condensate tank air injector return to boiler liquid ring pump steam turbine the most widely accepted method to identify air inleak. They hold the vaneshaped nozzles and seals between the stages. Maintenance cost of the gas turbine power plant is low and easier to maintain. In a practical situation the load frequently varies from the designed or economic load and thus there always exists a considerable.
A turbine stage normally consists of a row of stationary blading and a. It is not mechanically connected to the gas generator, but instead is mechanically coupled, 1. Power generation electrohydraulic control system improve. Theacti vatedunloader acts similarly to the loadlimiter, ie. Power pdf empowers you and your employees to combine multiple files into a single pdf complete with a table of contents. In general, a steam turbine is a rotary heat engine that converts thermal energy contained in the steam to mechanical energy or to electrical energy. The methods used for governing the steam turbines are.
Fromthe governor valve the steam passes through the lip turbine. The first steam turbine rail locomotive was built in 1908 for the officine meccaniche miani silvestri grodona comi, milan, italy. The kinetic energy leaving one stage and available to the next is given by. Lecture notes on renewable energy sources subject code. Approval issue module 2347 the turbine governing system. A combined cycle power plant consists of gas turbines, heat recovery steam generators, steam turbines and power generators. Lec11 basic concept of turbine, velocity diagram youtube.
It utilizes heat during the process and carries large quantities of heat later. Some energy sources have non energy uses, for example coal or natural gas can be. Flow of steam through nozzles, shapes of nozzles, effect of friction, critical pressure ratio,supersaturated flow. Fundamentals of fluid mechanics chapter 12 pumps and turbines jyhcherng shieh department of bioindustrial mechatronics engineering national taiwan university.
It steam power plant decreases the moisture content of the steam at the turbine exit as can be seen in ts diagram as shown in figure 2. Hydraulic turbines pelton wheel, francis turbine and kaplan turbine. A steam turbine locomotive engine is a steam locomotive driven by a steam turbine. Ensure that you keep your vital records secure while you. In the last lecture we have talked about the pelton turbine which is an impulse type of. The overall thermal efficiency of such systems can be in the range 70% to 80%. A gas turbine unit for power generation or a turbojet engine for production of thrust primarily consists of a compressor. Steam generator, turbine, condenser, feed pump, cycle net work, work ratio. There are two types of modern steam turbines impulse turbine in this type of turbine the steam nozzles direct superheated steam at the buckets of rotor blades, the impact of this causes the rotor to rotate.
Good morning, i welcome you all for the last topic of the course on fluid dynamics and turbo machines, that is steam and gas turbines. Superheating the steam to higher temperatures has very desirable effect. Steam turbines are also often applied in the renewable energy sector. Steam turbines are one of the most versatile and oldest prime mover technologies still in general production used to drive a generator or mechanical machinery.
Lecture series on steam and gas power systems by prof. Pdf power plant lecture notes chapter4 steam turbine. The air ejector draws out the air and vapours which are released from the condensing steam in the condenser. The temperature to which steam can be superheated is limited by metallurgical consideration. In an extracting type turbine, steam is released from variousin an extracting type turbine, steam is released from various stages of the turbine, and used for industrial process needs or sentstages of the turbine, and used for industrial process needs or sent to boiler feed water heater to. Power generation using steam turbines has been in use for about 100 years, when they replaced reciprocating steam. Hence, it could be used as a working substance for heat engines. As thelip turbine uses the latent heat in the steam, the steam becomes wet moist. Efficiency will depend on turbine size or rotor diameter, blade geometries, speed, extreme condition of steam and other losses. The lip turbine converts the latent heat ofthesteam to mechanical energy. Kofax power pdf editable pdf software helps individuals and businesses create editable pdf files, combine, and share with others without subscription fees. Onehalf of the diaphragm is fitted into the top of the casing, the other half into the bottom.
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