The purpose of the system is to enable the students to work out the characteristic curves of a kaplan turbine. Hydraulic turbine efficiency canadian science publishing. Effect of solidity on flow pattern in kaplan turbine runner ruchi khare, vishnu prasad, brijkishore abstract. Improvement of efficiency prediction for a kaplan turbine. The calculation of the pelton and francis turbine hill chart. The kaplan turbine is an inward flow reaction turbine, which means that the working fluid changes pressure as it moves through the turbine and gives up its energy. First, kaplan turbines normally operate in a wide range of discharges, thus cfd analysis of each variant of the runner should be carried out for several operation points. Q 11, n 11, model efficiency curve, electrical generator efficiency. Therefore, the overall efficiency curve is an envelope of partial efficiency curves, which are determined at a fixed angle of runner blades. With a split runner and turbine chamber, the turbine maintains its efficiency while the flow and load vary from 16 to. Pelton turbine was developed by lester allan pelton in the year 1870.
Kaplan turbines are low head hydraulic turbines doubly regulated. It also shows the efficiency curve for a propeller turbine a kaplan with fixed blades and fixed inlet guidevanes curve c. The specifics of the kaplan turbine are hub and tip clearance. Kaplan type hydraulic turbine in which the positions of the runner blades and the wicket gates are adjustable for load change with sustained efficiency, it is a purely axial flow turbine with a vertical shaft disposition. Cfd based optimization of kaplan turbine blade profile. Runaway transient simulation of a model kaplan turbine.
Kaplan turbines, bulb turbines, efficiency optimization, index test, combination curve. Vertical kaplan turbines suitable changes be made for other types. The turbine performance is good for a wide range of pressure heads, but improvements. Pdf priority of kaplan turbine and small hydropower.
Characteristic analysis of the efficiency hill chart of francis turbine. The pelton turbine is the most efficient of hydro turbines. The advantages of the kaplan turbine are listed below. Typical fixed and adjustableblade unit efficiency curves frequent index testing, especially before and after major maintenance activities on a turbine, should be made to detect changes in turbine performance at an early stage and establish controls 6. The andritz hydro kaplan turbine is utilized on a low head application with up to 90 m and a unit output of up to more than 230 mw. Pdf automatic system for efficiency optimization and calculation of. Difference between pelton, francis and kaplan turbines.
At the lower head, this kaplan turbine works much efficiently. Optimizing kaplan turbine efficiency with minimal cost. It was developed in 19 by austrian professor viktor kaplan, who combined automatically adjusted propeller blades with automatically adjusted wicket gates to achieve efficiency over a wide range of flow and water level. At large guide vane openings there is often a clearance between.
Pdf multiobjective shape optimization of runner blade. Pdf improvement of efficiency prediction for a kaplan. The kaplan turbine is a propellertype water turbine which has adjustable blades. Water flows both in and out of kaplan turbines along its rotational axis. Design and analysis of a kaplan turbine runner wheel avestia. Multiobjective shape optimization of runner blade for kaplan. It should be noted that the pelton, crossflow, and kaplan turbines attain high efficiencies in work points below designed flow. The kaplan is of the propeller type, similar to an airplane propeller. Further a manual separated operation of each guide vane servomotor will be. Hydraulics h46d kaplan turbine study unit code 934800. Apr 01, 2019 a variety of system problems could be solved by index testing kaplan turbines installed in the various facilities.
And if the head of the inlet of the turbine is the sum of pressure energy and kinetic energy during the flow of water through a runner a part of pressure energy is converted into kinetic energy, the. Turbines in hydropower hydropower plants can be equipped with different types of turbines depending on the head and discharge of the site to reach the highest possible efficiency. The turbine efficiency curve calculation is based on rated head design gross head less. The turbine operating parameters at these three operating points are presented in table 1. The difference in efficiency at full load is in the range of 2 % too 140 120 200 fig. These clearances have a significant impact on the velocity profile at the inlet of draft tube and accordingly draft tube losses. In general, the blades inletoutlet angles showed a significant. The disadvantages of kaplan turbine are as follows. Test of cam characteristic of the kaplan turbine by on.
Pdf kaplan turbine performance prediction using cfd. Kaplan turbine was developed by the austrian engineer victor kaplan towards the beginning of the 20th century. A kaplan runner wheel was theoretically designed to reach an efficiency of 94%. Kaplan turbines are often used for this frequency regulation in sweden since they have a high. The turbine efficiency should be entered according to the manufacturer datas. In addition, the data acquisition system must be checked against a manua. Specifications for otori power station the main specifications for units no. Multiobjective shape optimization of runner blade for. The generator has an umbrella structure, without an upper guide bearing. However, the cfd analyses showed that the same theoretical design only has an efficiency of 50. The pelton, francis and kaplan turbines are water turbines that are rotary machines which convert kinetic energy and the potential energy of the water into mechanical energy that rotates the shaft to produce electric energy. The presence of stationary and rotating blades in axial flow reaction turbine i.
It is regarded as the hydraulic turbine efficiency hill chart if all kinds of performance curves are plotted in a same graph. Characteristic analysis of the efficiency hill chart of. Some of the work developed by the turbine is used to drive the compressor, and the remainder is available for useful work at the output flange of the gas turbine. The main advantage with the xblade design is a flat efficiency curve with very. Modelling and analysis of a very low head kaplan turbine. An inclined or horizontal installation of the shaft. Each bucket splits the water jet in half, thus balancing the sideload forces or thrust on the wheel and thus the bearings. The project is based on the theoretical performance of the model to adapt it to the real conditions of. Kaplan turbines repositorio cientifico do instituto. The original design could be improved to achieve an efficiency of 93. The type of turbine is entered by the user based on its suitability to the available head and flow conditions. The object of obtaining this curve is to determine the zone of constant efficiency so that we can always run the turbine with maximum efficiency. The turbine units proposed for the swansea bay and cardiff bay tidal lagoons are similar variableblade propeller or kaplan bulb turbines.
Multiobjective shape optimization of runner blade for kaplan turbine. Relative efficiency measurements using the winterkennedy method for relative flow determination are a popular method for. Design of hydro power by using turbines kaplan on the discharge. Feb 06, 2017 all performance curves on the model efficiency hill chart, for example, the output limiting curve, cavitation inception curve of blade leading edge, cavitation vortex curve, and others, are the natural characteristics of francis turbine, which cannot be eliminated but can be adjusted in a small range by means of hydraulic design strategy. The vertical configuration of the kaplan turbine allows for larger runner diameters above 10 m and increased unit power, as compared to bulb turbines. Mrc workshop on fish and hydropower 8 species study method. Effect of solidity on flow pattern in kaplan turbine runner. A kaplan turbine is a type of propeller hydro turbine specifically a reaction turbine used in hydroelectric plants. Range of utilization the kaplan turbine has an outstanding reputation for its high specific flow capacity. Hydraulic turbines gives their best performance when they are operated at certain conditions of head, discharge, speed and output power. Model turbines are tested under different conditions of head, discharge, speed, power, efficiency. Values of discharge, torque and losses obtained by different turbulence models are compared to each other and to the measurements.
As a doubleregulated turbine it is therefore most suitable for low heads and large flows, but also for. Steady multirow viscous singlephase analysis has been applied to compute the flow field from the inlet struts to the runner exit. The degree of efficiency is very high with more than 95 %. Selecting hydraulic reaction turbines bureau of reclamation. Layout of kaplan turbine at jhang branch canal in punjab, pakistan. Performance, model testing, speed, model testing and.
Kaplan turbine and francis turbine, as well as pump tur bine in a closedloop or. Results are plotted in the form of curves and are known as performance characteristic curves. For a kaplan turbine, it depicts the model as though it were operating with its optimum 3d bladetogate cam. Engineered to respond instantly to variations in demand. Efficiency and flow as a function of head and operating speed are typically summarized on a turbine performance hill curve. The peak efficiency of a crossflow turbine is somewhat less than a kaplan, francis or pelton turbine.
An electrically operated centrifugal pump transfers the water under pressure from the main tank to the turbine, simulating the. The cam curve determines the relation between the guide vane angle and runner blade angle for an optimum efficiency independently of the flow rate. One of the important factors in the comparison of hydro power systems is available efficiency. The design of hydraulic turbines is based on energetic and cavitation characteristics, obtained by measuring the turbine models in the test rig. Turbine selection criteria for small hydropower development.
Hap best practice catalog propellerkaplan turbine 2012. Actually, the turbine efficiency depends on the turbines power, the turbines type, fluid percentage, etc. Commissioning of 87,000kw kaplan turbine and generator for. Specify as per flow duration curve for annual energy 7.
The inlet is a scrollshaped tube that wraps around the turbines. Pdf design and analysis of a kaplan turbine runner wheel. Typically, more than 50% of the work developed by the turbine sections is used to power the axial flow compressor. Apr 08, 2015 the kaplan turbine is a water turbine which has adjustable blades and is used for low heads and high discharges. Therefore efficiency computation of kaplan turbines should account the flow in the gaps. The ice harbor powerhouse 603 mw has six kaplan units. Classification of turbines the low head kaplan turbine at the jhang branch canal in punjab, pakistan is a micro hydro power turbine.
These units have a generating capacity of 20 mw and are designed for bidirectional generation, so that power can be produced on both the ebb and the flow tide. The guide vanes angle corresponding to the best efficiency point of the investigated propeller curve was found to be 26. In addition, the data acquisition system must be checked against a manual. It was developed in 19 by austrian professor viktor kaplan, who combined automatically adjusted propeller blades with automatically adjusted wicket gates. Jul 01, 2010 this method may be used on any hydraulic reaction turbine, including francis and, in particular, kaplan turbines. Our kaplan turbines also keep the environment in mind. August 19, the kaplan turbine, as it is known today, was invented by viktor kaplan in austria 3, 7. Commissioning of 87,000kw kaplan turbine and generator. Limits of operation is the performance range of the turbine e. Next, due to a high specific speed, draft tube losses have a great impact on the overall turbine efficiency, and thus should be accurately evaluated.
Introduction low head kaplan and bulb turbines have a very large market potential in brazil. Each unit intake has three bays and is equipped with a standardlength submersible traveling screen which diverts about 90% of juvenile outmigrants into a bypass system. This kaplan turbine was developed in 19 by viktor kaplan, an austrian professor. Isopower cam curve testing for optimal bladeswicket gates law for kaplan turbines j. The efficiency of the kaplan turbine is very high compared to others. General arrangements for pelton, francis, kaplan and kaplan bulb turbine. Kaplan turbine the kaplan turbine is a great development of early 20th century. Kaplan turbine may be observed that its efficiency is reaching to the maximum value for a various flow rate of water, proving these kinds of turbines can be desirable for a.
For kaplan and bulb turbines, the socalled combination curve or cam. The bidder shall guarantee the weighted average efficiency of the turbine at rated net head using the. Kaplan turbine makes the flow complex in the turbine space. Hap best practice catalog propeller kaplan turbine rev. With a double regulation system, kaplan turbines provide high efficiency over a broad range of configurations.
In his design, he combined automatically adjusted propeller blades and guided vanes to obtain efficiency over a wide range of water flow. Indexing is essentially tuning a kaplan turbine to maximize its operating efficiency. Charts showing the relationship between calculated. To achieve optimum efficiency at varying flows, the runner blades are automatically adjusted in relation to the wicket gate position. Testing efficiency and characteristics of a kaplantype small turbine. Therefore, in this article, we will discuss the kaplan turbine with its. A hill curve depicts the optimum performance of the model. An inclined or horizontal installation of the shaft is.
However, the crossflow turbine has a flat efficiency curve under varying load. Influence of pressure difference exponent value on efficiency characteristics. These curves are plotted from data which can be obtained from the constant head and constant speed curves. Isopower cam curve testing for optimal bladeswicket. While kaplan turbines are very expensive to design, manufacture and install, they operate for decades wikipedia kaplan turbine. Hydraulic turbines gives their best performance when they are operated at certain conditions of head, discharge, speed and. Kaplan turbine may be observed that its efficiency is reaching to the maximum value for a various flow rate of water, proving these kinds of turbines can be desirable for a river with a variant in. The turbine, which has a 5,100mm diameter runner with movable blades, is a vertical axis spiraltype kaplan turbine. Figure 3 efficiency curve comparison between francis and kaplan 2. Finally, this new family of curves is implemented on alstoms speed governor so that the generating unit will be at its best efficiency at any head. When the water flows parallel to the axis of the rotation of the shaft, the turbine is known as the axial flow turbine. The calculus algorithm is based on the polynomial representation of the working performance curve. Figure 3 below shows how the efficiency varies across the operating flow range for a full kaplan curve a, a semi kaplan with adjustable blades curve b and a semi kaplan with adjustable inlet guidevanes curve d.
Kaplan turbines are widely used throughout the world in the lowest head hydro sites. The calculation of the pelton and francis turbine hill. The efficiency of the kaplan turbine is very high as compares with other types of hydraulic turbines. Design and analysis of a kaplan turbine runner wheel. They are designed to operate at the highest possible efficiency, typically over 90%. Effects of load variation on a kaplan turbine runner. What makes kaplan turbines special is the blades can change their angle on demand to maintain maximum efficiency for different flow rates of water. A comparison between numerical simulations and measurements of a sixblade kaplan turbine is presented in order to determine an appropriate numerical setup for accurate and reliable simulations of kaplan turbines. This turbine work more efficiently at low water head and high flow rates as compared with other turbines. Next specific feature of kaplan turbines is the presence of gaps between blade and hub, and between blade tip and runner chamber.
Review of existing knowledge on the effectiveness and. The kaplan turbine is a propeller type water turbine with 4 to 7 adjustable blades. Some features of the low head kaplan turbine are the following turbine runner diameter d 1. Kaplan efficiency improvement system complete reivax. Pdf priority of kaplan turbine and small hydropower plants.
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