Proposed was a universal method for calculating the powerbackpressure characteristics i. Please note that this is a generic tool developed by the us department of energy, and that more precise results for elliott steam turbine generators with controlled andor. Turbine speed 7,700 rpm compressor pressure ratio 14. In 1924 krupp built the steam turbine locomotive t18 001, operational in 1929, for deutsche reichsbahn. Back pressure turbine how is back pressure turbine abbreviated. Extraction condensing turbine an overview sciencedirect topics. Now keep this structure in mind and imagine i put a set of turbine blades in the path of this highpressure. Consider installing highpressure boilers with backpressure. A steam backpressure turbine is a device that converts the thermal energy of steam into mechanical work. Pdf with a 660mw ultrasupercritical steam turbine unit as the research object, the back pressure correction curves of the unit tha condition and. So you put a more free flowing exhaust system on the vehicle, put a lower inlet restriction ais on the front side and the engine dynos 65 hp higher with a calibration tweak. Backpressure turbine extraction cum backpressure the extraction backpressure steam turbine is designed for plants, which require two different pressures and temperatures, and which also need electric power. This low pressure steam uses for processing and no steam is used for condensation.
The pressure of outlet steam depends on in the load, therefore, this turbine is also known as the back pressure steam turbine. Steam turbines, operation, supersaturation, moisture, back pressure. The name condensing turbine and back pressure turbine expressed about steam condition exit the turbines. Pdf calculation method of back pressure correction coefficient of. A turbine generator can often produce enough electricity to justify the capital cost of purchasing the higher pressure boiler and the turbine generator. Back pressure steam turbines or noncondensing turbines are most widely used for process steam applications.
When specifying a new boiler, consider a highpressure boiler with a backpressure steam turbinegenerator placed between the boiler and the steam. Back pressure turbines are available in single stage or multistage options. Steam turbine 560 is designed for isentropic heat drop of steam higher than 120 kjkg1 with the option of controlling two partial sprays. What is the difference between fully condensing and back. The turbine stayed the same but the effect was 65 hp higher power. How the exhaust pressure for a steam turbine is selected. The popularity of process steam as an energy source stems from its many advantages, which include high heat capacity. The exhaust pressure is free to move in the optimization cases, since the actual. May 05, 2017 all steam turbines can be classified into two categories. The back pressure turbine refers to a steam turbine that has a higher exhaust pressure than the atmospheric pressure.
A steam turbine fundamentally consists of a rotor carrying blades, the casing in which the rotor turns, and the nozzles through which the steam is allowed to expand. Back pressure detects when vital system resources, such as hard drive space and memory, are overused, and takes action to prevent the server from becoming completely overwhelmed and. Noncondensing or back pressure turbines are most widely used for process steam. Steam backpressure turbines are used as the prime movers in industry in the following applications. The first steam turbine used for power generation was invented in 1884.
Primarily, this kind of turbine is used as a reducing station between boiler unit and the process steam header. For same power rating the cost of turbine is less compared to condensing turbine due to its small size. The schematic diagram of the back process steam turbine with cogeneration system is shown in figure 2. These turbines can either be used for drive application sugar mill drives, sugar fibrizor shredder drive, pump drives and so on or power generation application in which case the turbine drives the generator. Backpressure steam turbine backpressure steam turbine schema. Back pressure or backpressure is a resistance or force opposing the desired flow of fluid through pipes, leading to friction loss and pressure drop. Based on this method, the choked back pressure for each operation load can be determined. Pdf calculation of the choked back pressure for steam turbines. An extractioncondensing type of steam turbine can be used in combined cycles and be. What is a back pressure steam turbine and what is its role in. In doing so, energy is consumed rather than produced.
The parameters for back pressure steam turbine cogeneration plant is given below inlet steam. If steam condition exit the turbine in wet steam or where steam. How exactly the exhaust pressure for a steam turbine is selected. The turbine stage is in two basic modifications a radial stage and an axial stage. Steam is a principle energy source for many industrial processes. Nov 07, 2016 back pressure steam turbine is also called as non condensing steam turbine is mostly used in process steam industries or cogeneration plants. The popularity of process steam as an energy source stems from its many advantages, which include. Proposed was a universal method for calculating the power back pressure characteristics i. Backpressure turbine how is backpressure turbine abbreviated. The first steam turbine rail locomotive was built in 1908 for the officine meccaniche miani silvestri grodona comi, milan, italy. Aug 12, 2015 these results were used in a highfidelity 2d thermal modeling of the power turbine to study the impact of back pressure on turbine disc thermal characteristics and their lives. The boiler generates steam using coal, natural gas or other fuels such as biomass, and the superhot, high pressure steam runs a turbine to generate electricity.
The machine set can work both in a condensation and a counter pressure system back pressure. The exhaust of an automotive system usually contains a mufflerexhaust aftertreatment device, and a exhaust pipesometimes called a tail pipe. Types of steam turbines turbines info wind turbine, steam. Our steam turbines serve a vast range of industries ranging from food and sugar to biomass and textiles and beyond. A steam turbine locomotive engine is a steam locomotive driven by a steam turbine. Calculation of the choked back pressure for steam turbines. The noncondensing steam turbine uses high pressure steam for the rotation of blades. Steam turbines have been used to generate power for about 100 years, after plants began to replace their older reciprocating steam engines.
A steam based power generation unit is a combination of boiler and turbine. Back pressure turbines are commonly employed in industrial plants where a large quantity of steam is required. A steam turbine is a device that extracts thermal energy from pressurized steam and uses it to. In some processes, sufficient back pressure will exceed maximum operating pressure causing some component of the process to fail. Electric generators calculations the output power of the turbine depends on the mass flow rate of steam, the turbine efficiency, and the. Steam turbines startups 1 principles of steam turbines startups.
Impact of high exhaust back pressure on power turbine. The fluid and thermal predictions were validated using normal back pressure fullscale fullload test results. If you use a flowmeter to measure flow rate, you must consider the effect of back pressure. The volume of exhaust gas may be the same per given hp but the main factor to consider is at what pressure a given turbo may be rated at 1200hp but on a v8 operating at low boost levels the turbine side may be too small and not flow enough exhaust gas without the exhaust pressure spiking. Back pressure steam turbines can either be used for drive application sugar mill drives, sugar fibrizor shredder drive, pump drives and so on or power generation application in which case the turbine drives the generator.
An example was given for a supercritical, regenerative singleshaft, 2casing with 2exhaust steam turbine generation unit with air cooled condenser. A pressure reducing valve drops the buildings steam pressure. Energy performance assessment of cogeneration and turbines gas, steam bureau of energy efficiency 45 3. I peeped in the pdf, and i think, concerning the efficiencies stated. Back pressure article about back pressure by the free. Since boiler fuel usage per unit of steam production increases with boiler pressure. Goal install a noncondensing backpressure steam turbine that produces energy while. A turbine generator can often produce enough electricity to justify the capital cost of. Usually this type of turbines are used in cogen applications.
The highpressure exhaust gas should be released and it will have no way but backward. These turbines are straight back pressure type and find application where back pressure steam is fully utilized to meet process demands. I understand that depending on the turbine size, there is a sweet spot at which the increase in efficiency by lowering the exhaust. 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. Scribd is the worlds largest social reading and publishing site. For the rankine cycle we assume one stage of pumping which is adiabatic and the power input to the pump is p in m. Pdf calculation method of back pressure correction. Steam turbine portfolio overview digital asset management. Extraction cum backpressure backpressure turbine power. Alternatively, partial admission of the impeller is used.
As a kind of commonly used power plant equipment, this range of back pressure steam turbines can be used for driving water pump and draught fan, as well as the combined heat and power generation, such as the cases in public thermal power station, and the private power station. Some of the back pressure might be caused by the exhaust downstream. Backpressure steam turbines or noncondensing turbines are most widely used for process steam applications. In reality there are many things which are done to the feed water before it goes back into the boiler and the pressure is often raised in several stages. The term back pressure is a misnomer, as pressure is a scalar quantity, so it has a magnitude but no direction. Consider installing high pressure boilers with backpressure turbine generators when specifying a new boiler, consider a high pressure boiler with a backpressure steam turbine generator placed between the boiler and the steam distribution network. Types of steam turbines back pressure steam turbine manufacturer. The extraction condensing turbine is able to change the electric power and the. Home consider installing highpressure boilers with backpressure turbinegenerators this tip sheet outlines the benefits of highpressure boilers with backpressure turbinegenerators as part of optimized steam systems. This turbine generates low or medium pressure steam as required for the plant. Back pressure is a system resource monitoring feature of the microsoft exchange transport service that exists on mailbox servers and edge transport servers. 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. How to calculate exhaust gas back pressure in automobiles.
Pdf on jan 1, 20, haisheng yang and others published calculation of the choked back pressure for steam turbines. Types of steam turbines back pressure steam turbine. Can be built in small or very large units up to 1200 mw. Steam turbine cogeneration systems involve different types of configurations with.
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