An organic solvent is mixed with the amine polymer to adjust its application viscosity. In nuclear power plants, the heat source used is usually a nuclear reactor. Nevertheless modern steam turbines are very efficient and operate with internal efficiencies within the range of 80 percent to 90 percent depending upon the steam conditions. View and download powerpoint presentations on steam turbine ppt. This paper presents the simulation study on the effects of mechanical turbo compounding on a turbocharged diesel engine. The moving blades are running at horizontal direction with a tangential velocity v and v 2 the absolute velocity of steam leaving of moving blades create an angle. It is the process by which rotor speed come to its desired value. This type of compounding is known as the pressure compounding and the nozzle and blade arrangement for a pressure compounded impulse turbine is sketched.
In fact, a series of velocitycompounded impulse stages is called a. In case of turbines with cooling water preheating and lowpressure lp bypass, prior to supplying steam the regeneration and dumping systems have to be. Improved steam turbine design for optimum efficiency and. Therefore, for good efficiency the blade velocity should be about one half of the steam velocity.
Compounding of steam turbines is the method in which energy from the steam is extracted in a number of stages rather than a single stage in a turbine. Development of tandemcompound 1,000mw steam turbine and. This highvelocity strikes the turbines rotor and the speed. Because the turbine generates rotary motion, it is particularly suited to driving electrical generators about 90% of all electricity generation in the united states 1996 is by use of steam turbines 1 wiser. Steam turbine drives may be installed for continuous duty under severe operating conditions, or used for load shaping e. In noncondensing turbines or backpressure turbines, steam exhausts at a pressure greater than. This method of compounding is used in rateau and zoelly turbines.
Steam consumption of steam turbine is depending to required output power and efficiency of the turbine. A steam turbine is a mechanical device that extracts thermal energy from pressurized steam and transforms it into mechanical work. In order for the steam to give up all its kinetic energy to the moving blades in an impulse turbine, it should leave the blades at zero absolute velocity. It is a combination of the above two types of compounding. Latest technologies and future prospects for a new steam turbine. The steam from the boiler is expanded in a nozzle, resulting in the emission of a high velocity jet. Steam process in steam turbine steam entrance to turbine through governor valv e to control steam capacity and therefore to control turbine speed. Only a small fraction of the overall pressure drop available in a turbine can be extracted in a single stage consisting of a set of stationary nozzles or vanes and moving blades or buckets. Consider steam turbine drives for rotating equipment. Pressure compounding of an impulse turbine is the use of a number of stages of nozzle and blade to reduce progressively the steam pressure. Free kindle book and epub digitized and proofread by project gutenberg. In all turbines the rotating blade velocity is proportional to the steam velocity passing over the blade. Pressurevelocity compounding curtis turbine curtis turbine pressurevelocity compounding. The steam turbine is a turbine in which the potential energy of heated and compressed steam produced in a special device, a steam generator, or steam of natural origin for example, from geothermal springs is converted into kinetic energy when the steam expands in the turbine blade cascades and then into mechanical work on the rotating shaft.
Compounding of steam turbines is the strategy in which energy from the steam is extracted in a. So, steams pressure drop and it will increase its velocity. The technical specification of the tc4f40 1,000mw and 700mw steam turbines is shown in table 2. Approval issue module 2347 the turbine governing system. A condenser installed at the exhaust or low pressure end of the turbine receives and condenses the steam prior to it being pumped back to the boiler. A compound steam engine unit is a type of steam engine where steam is expanded in two or more stages. Velocitycompounded impulse turbinevelocity compounded impulse turbine curtis stage turbinecurtis. Necessity the steam produced in the boiler has sufficiently high enthalpy when superheated.
Jan 02, 2009 free kindle book and epub digitized and proofread by project gutenberg. Pdf power plant lecture notes chapter4 steam turbine. There are two classical types of turbine stage designs. Steam turbine governing is the procedure of controlling the flow rate of steam. In contrast to water turbines where the total head is extracted in a single runner see above, the steam velocities obtained from the enthalpy drop between steam. Therefore, for good efficiency the blade velocity should be about one. Summary of the key concepts the load limiter restricts the maximum allowable turbine generator load. Downtime can be expensive and unplanned downtime can be extremely disruptive. Steam for turbine is provided by pp330140p55 type steam generator, a oncethrough coalfired boiler 8. Compounding of steam turbine 232 reaction turbine 233 losses in steam turbine 235 reheat factor 236. Definition a steam turbine is a prime mover in which the potential energy of the steam is transformed into kinetic energy and later in its turn is transformed into the mechanical energy of rotation of the turbine shaft. This v r2 can be obtain by subtracting the v and v 2 and it create some angle f 1. Fundamentals of steam turbine systems principles of operation the motive power in a steam turbine is obtained by the rate of change in momentum of a high velocity jet of steam impinging on a curved blade which is free to rotate. Applications of steam turbines power generation transport 4.
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. Pressure compounding is the method in which pressure in a steam turbine is made to drop in a number of stages rather than in a single nozzle. Figure 4 shows steam process in enthalpy against entropy diagram of curtis and single row rateau turbine. These steam turbine chp installations have an average capacity of 37 mw and a combined capacity of 26 gw, representing 32% of the installed chp capacity in the united states.
Outline introductionintroduction work diagram work diagram blade stagingblade staging. A downstream powerturbine has been coupled to the exhaust manifold after. Classification of steam turbines according to the steam conditions at inlet to turbine. In order to meet the requirements of rising energy demand, one goal in the design process of modern steam turbines is to achieve high efficiencies. Aug 19, 20 a condenser installed at the exhaust or low pressure end of the turbine receives and condenses the steam prior to it being pumped back to the boiler. Us4895696a steam turbine preservative and method of. The method in which energy from steam is extracted in more than single stage is called compounding. Steam turbine performance is expressed in terms of isentropic efficiency or steam rate the steam requirement of the turbine per unit of shaft power produced. Compounding of steam turbine mechanics rotating machines. The rand woodbury illusionworks pdf pressure compounded impulse turbine is also called as rateau turbine, after its.
Oct 28, 2016 10 awesome gadgets every student should have. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. In this type, the total pressure drop expansion of the steam take place only in the first nozzle ring. Cross compound steam turbine arrangement compounding is the splitting up, into two or more stages, of the steam pressure or velocity change through a turbine.
Compounding of steam turbines is the strategy in which energy from the steam is extracted in a number of stages rather than a single stage in a turbine. A steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into rotary motion. Unesco eolss sample chapters thermal power plants vol. A multiple system of rotors are connected in series keyed to a common shaft and the steam pressure or velocity is absorbed in stages as it flows over the blades. The best way to ensure the longterm performance of your elliott stg is through a collaborative maintenance agreement with elliott field service.
It has almost completely replaced the reciprocating piston steam engine primarily because of its greater thermal efficiency and higher powertoweight ratio. Cross compound steam turbine arrangement for marine use. Impulse stages may be either pressurecompounded, velocitycompounded, or pressurevelocity compounded. This condition will exist if the blade velocity is equal to one half of the steam velocity.
A properly maintained elliott steam turbine generator stg can operate reliably and efficiently for decades. Steam expands from boiler pressure to the condenser in one stage. Steam turbine convert a part of the energy of the steam evidenced by high. Schematic diagram of 200 mw unit 8 construction of the steam generator is carried out in two distinct bodies, symmetrical with the axis of the group, operating in parallel to the k2001 steam turbine. A rotor of a modern steam turbine, used in a power plant.
The steam coming from the boiler is fed to the first set of fixed blades i. What links here related changes upload file special pages permanent link page information wikidata item cite this page. Principles of operation of a steam turbinewhen high temperature steam passes through a steam turbine. Rateau turbine pdf pressure compounding is the method in which pressure in a steam turbine is made to. In this arrangement, the pressure of the steam drops in each set of nozzles as indicated by the pressure graph. Latest technologies and future prospects for a new steam. The invention of parsons steam turbine made cheap and plentiful electricity possible and revolutionized marine transport and naval warfare. Feb 19, 2017 lecture series on steam and gas power systems by prof.
Compounding of steam turbine is used to reduce the rotor speed. These arrangements include single casing, tandem compound and cross compound turbines. A downstream power turbine has been coupled to the exhaust manifold after. The pressurevelocity compounding is a combination of the above two types of compounding. Three methods of compounding in steam turbines a media to. Efficiency will depend on turbine size or rotor diameter, blade geometries, speed, extreme condition of steam and other losses. To improve the thermal efficiency of any power plant, generally high pressure near about 120 to 140 bar, high temperature and highvelocity steam is used. But for smooth flowing of the steam while existing, it creates an angle of. This divides the velocity drop across the stage into several smaller drops. Compounding of steam turbine free download as pdf file. Influence of compound lean on an industrial steam turbine stage.
In this the steam is first expanded in a set of nozzles or passages upto exit pressure where in the pressure energy of steam is converted into kinetic energy. Steam turbine gets heat energy in the form of superheated steam from steam generator. A major gain in efficiency is expected from the optimization of the last stage of a low pressure turbine lp. Reaction turbine blading and conditions figure 3 shows, at the top, the end view of four stages of fixed and moving blades of an. Compounding in impulse turbine compounding of steam turbines is the method in which energy from the steam is extracted in a number of stages rather than a single stage in a turbine. Chaplin encyclopedia of life support systems eolss figure 4.
Aerodynamic optimization of the nozzle for the last stage. This highvelocity strikes the turbines rotor and the speed of the rotor becomes high. The nozzles are fitted to the casing and the blades are keyed to the turbine shaft. These turbines use steam up to a pressure of 40 ata. Find powerpoint presentations and slides using the power of, find free presentations research about steam turbine ppt. The modern steam turbine was invented in 1884 by sir charles parsons, whose first model was connected to a dynamo that generated 7. In this type of compounding the steam is expanded in a number of stages, instead of just one nozzle in the velocity compounding. What is velocity and pressure compounding in impulse turbine. So, steam s pressure drop and it will increase its velocity. Steam turbines their construction, selection and operation pdf. Steam turbine compounding of steam turbine mechanicaltutorial. A velocitycompounded impulse stage consist of a row of fixed nozzles followed by two or more rows of moving blades and fixed blades without expansion.
A typical arrangement for a compound engine is that the steam is first expanded in a highpressure hp cylinder, then having given up heat and losing pressure, it exhausts directly into one or more largervolume lowpressure lp cylinders. This paper presents the simulation study on the effects of mechanical turbocompounding on a turbocharged diesel engine. A steam turbine preservative and method of preserving steam turbine components involves the application of an amine polymer as a nonaqueous layer to the surfaces of such components. Course 234 turbine and auxiliaries module seven approval issue pagel8 7. In modern steam engine practice high pressure steam is used, as the use of such a. The turbine steam flow would increase, causing unloading to recur again. Following figures show steam process in steam turbine. Compounding of steam turbine turbine turbomachinery scribd. Combined heat and power technology fact sheets series. Lecture series on steam and gas power systems by prof. Basically, there are two ways of compounding steam turbines. Compounding of steam turbine free download as powerpoint presentation. Moreover, 50inch blades for 3600 rpm and 60inch blades for 3000 rpm with further enhanced. There are three major forms of compounding turbines which include the velocity compounding, pressure compounding, and pressurevelocity compounding.
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