Construction and working of francis turbine pdf runner

Twentytwo of the francis turbines reside in hoover dam to this day. The francis turbine is a type of water turbine that was developed by james b. This textbook is about principles of turbine machinery. Francis turbine diagram, working, parts, advantages. It is an inward flow reaction turbine that combines radial and axial flow concepts. Kaplan turbine it is an axial flow reaction turbine. To study constructional features of francis turbine bme. A reaction turbine is a type of turbine in which the working fluid comes to the turbine under great pressure and the energy is extracted by the turbine blades from the working fluid generally water unlike pelton turbine in which all the energy of. The measured stress amplitudes on a runner blade outlet caused by blade passing of the guide vane wakes pressure are illustrated in fig. This turbine is used for medium heads with medium discharge. Runner of francis turbine the shape of the blades of a francis runner is complex. The lower half is made in the shape of a small bucket so that it uses the impulse action of water to rotate the turbine.

May 30, 2018 these are axial flow, radial flow and mixed flow type runners. Outlet draft tube outlet runner inlet runner outlet guide vane inlet guide vane. Francis turbine is the first hydraulic turbine with radial inflow. The radial vanes are so shaped that the water enters and leaves the runner without shock. The average velocity of water in nominal capacity of turbine in main pipeline is 8. May 15, 2019 getai hydropower is a china supplier of francis turbine, francis turbine generator, francis turbine parts, francis runner, construction and working of francis turbine. 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. Francis turbines are very able to sustain the high mechanical stress resulting from high heads. Francis turbines are the most commonly used hydro turbines. Kaplan turbine is employed, where a large quantity of water is available. The exit of the francis turbine is at the center of the runner plate. The francis turbine, named for him, is the first modern water turbine.

In francis turbine water flow is radial into the turbine and exits the turbine axially. Francis turbine is a combination of both impulse and reaction turbine, where the blades. Francis turbine spiral casing draft tube cone governing ring guide vanes stay vanes runner labyrinth seals. The water looses a part of its pressure in the volute spiral casing to maintain its speed. A francis turbine consists of the 5 main parts those are. In this study the cfd analysis of a francis hydraulic turbine is carried out which was selected for operation at a.

It constitutes a closed passage whose crosssectional area gradually decreases along the flow direction. Mar 21, 20 the radial vanes are so shaped that the water enters and leaves the runner without shock. Apr 08, 2015 the kaplan turbine is a water turbine which has adjustable blades and is used for low heads and high discharges. It consists of spiral casing, guide mechanism and draft tube of kaplan turbine runner are similar to those of francis turbine. Francis turbine variation in the operating head can be more simply controlled. Francis turbines are generally installed with their axis vertical. State of the sprinter chooses the stream of water through the turbine. The mechanical efficiency of the pelton wheel turbine decreases faster than the francis turbine. May 02, 20 with help of 3d animation working and design aspects of a kaplan turbine is elaborated in this video lecture. The francis turbine is a mixed flow reaction turbine. The dimensions of these parts are dependent practically all dimensions, features and characteristics of the desired turbine can be expressed as a function of the specific speed. Since it is a reaction turbine, so the reaction force of leaving water is used to turn the runner of the kaplan turbine, as the water flows through the twisted blades a lift force is generated in the opposite direction of the leaving water and that lift force causes the blades to rotate. The kaplan turbine is a water turbine which has adjustable blades and is used for low heads and high discharges.

The static pressure that acts on the main inlet valve located just before the turbine is 1. With decades of continuous optimization based on the latest hydrodynamic research, well over half the turbines manufactured by voith hydro are of the francis type. This is the only impulse type of hydraulic turbine named after lester a. Therefore, in this article, we can discuss both the kaplan turbine and reaction turbine so that we can complete the. The runner consists of a circular disc with a suitable number of double semiellipsoidal cups known as buckets which are evenly spaced around its periphery. The 3d animation shows how the parts of the francis turbine produce electricity. The steam expands first in the stationary or fixed blades where it gains some velocity as it drops in pressure. Water pressure decreases as it passes through the turbine imparting reaction on the turbine blades making the turbine rotate. Kaplan turbine its components, working and application.

This requires that the runner should admit a comparatively large quantity of water for a given power output and. Francis turbine runner using computation fluid dynamics an international multidisciplinary journal, ethiopia, vol. Aug 20, 2019 the turbine capable of working under the high potential head of water is the pelton wheel turbine which works on the head greater than 300 m. The main difference between the turgo and pelton turbine is the.

Design, performance and maintenance of francis turbines. Turgo turbine was developed gilkes energy company in 1919. The components are arranged in sequential order of how water enters into the spiral casing and makes the runner rotate and how it exits from the draft tube to the tailrace generating electricity was explained below. Parametrical and theoretical design of a francis turbine runner with the help of computational fluid dynamics conference paper pdf available july 2014 with 5,151 reads how we measure reads. As discussed above, it is a type of reaction turbine. These are axial flow, radial flow and mixed flow type runners. The spiral casing around the runner of the turbine is known as the volute casing or scroll case. Francis turbine is the most common type of turbine in practice, which presents a sidebyside design of generator. Throughout its length, it has numerous openings at regular intervals to allow the working fluid to impinge on the blades of the runner. Impulse turbine and reaction turbineprinciple, working.

The performance and efficiency of the turbine is dependent on the design of the runner blades. Water with high head pressure enters the turbine through the spiral casing surrounding the guide vanes. First, a theoretical design was performed for determining the main characteristics where it showed an efficiency of 94%. See more ideas about francis turbine, shenyang and organizational structure. Main components of the francis turbine are sprial case,stay vanes,guide vanes,turbine runner and draft tube. The author compared the result with the test experiment of jhimruk hps 7. A brief discussion on a the design philosophy during the last 60 years with will be presented. Stay vanes and guide vanes guides the water to the runner blades. During the course of flow, water glides over runner blades as shown in figure below. These turbines can be used for heads as low as 2 meters and as high as 300 meters. The lower half is made in the shape of small bucket so that it uses the impulse action of water to rotate the turbine.

Water passes through various components of the francis turbine to rotate the runner and generates electricity. 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. From the beginning, francis turbine development has always been synonymous with voith. Abstract the aim for turbine design is to increase the efficiency and avoid cavitation and fractures during operation. Kaplan turbine and francis turbine pdfcomponents, working.

Shape of the runner decides the flow of water through the turbine. Ge has successfully completed numerous installations of francis turbines with outputs up to 800 mw, including one of the largest francis turbines ever made each with a runner diameter of 10 meters and weighing over 450 tons. Water turbines are mostly found in dams to generate electric power from water potential energy. Reaction turbines are classifies according to the direction of flow of water with respect to runner. In a francis turbine, runner blades are divided into 2 parts. Here importance of turbine runner, runner blade shape, spiral casing and draft. The francis runner traditional runner x blade runner 10. Additionally, these turbines are beneficial as they work equally well when positioned horizontally as they do when they are oriented vertically. Francis turbine diagram, working, parts, advantages, applications. It is still the most widely used water turbine in the world today.

Water enters the turbine through spiral casing, and starts entering the runner blades, passing through stay vanes and guide vanes, as it moves along the length of casing the decreasing crosssection area of the spiral casing makes sure that the pressure energy of water would remain uniform along its length. His work on these turbines was later published as the lowell hydraulic experiments in 1855. Pdf design analysis of parts of francis turbine researchgate. In runner water enters radially, and leaves axially. Dec 17, 2019 the turbine size runner, generator and powerhouse required is large. In this article we will learn about how francis turbine working principle, main components. Mathematical modeling for the design of francis runner software for 3d modeling and used ansys cfx for design optimization.

Pelton wheel is the preferred turbine for hydropower when the available water source has a relatively high hydraulic head at low flow rates. The design of this impulse water turbine is inspired from pelton turbine. Introduction to turbine machinery university of ljubljana. A francis turbine consists of the following main parts. Planning, construction and rehabilitation of hydropower stations have. The inlet is a scrollshaped tube that wraps around the turbines. His design is extremely flexible and can be tailored to different head heights and flow rates. Main parts of francis turbines francis turbine reaction turbine.

The parameters of turbine runner affect the hydraulic performance of turbines. The francis turbine was developed by an american engineer james bichens francis around 1855. Losses in francis turbines npsh main dimensions francis turbines. Choose us, you can be get most careful and thoughtful service. The efficiency of a turbine is highly influenced by its runner wheel and this work aims to study the design of a kaplan turbine runner wheel. The normalized losses and efficiencies at runner speed of500rpm. It converts the kinetic energy from the water jet into mechanical energy. It is obvious from the equation of specific speed eq.

The turbine runner consists of a series of curved vanes uniformly fitted. They operate in a head range of ten meters to several hundred meters and are primarily used for electrical power production and their output varies from a few kilowatts to. In a francis turbine, the runner blades are divided into two parts. The inlet is a scrollshaped tube that wraps around the turbine s. These two forces together makes the runner to rotate. The francis turbine is an inward flow reaction turbine which was designed and developed by the american engineer james b. The runner of the francis turbine is made up of cast iron, cast steel and stainless steel. It is a large size conduit which conveys water from the upstream to the damreservoir to the turbine runner. Francis turbine has two cases, in first one simple francis turbine i.

The performance and efficiency of the francis turbine are dependent on the design of the runner blades. This operates in an entirely closed conduit to tailrace. Water enters the runner and flows towards the center of the wheel in the radial direction and leaves parallel to the axis of the turbine. The turbine size runner, generator and powerhouse required is large.

To study constructional features of francis turbine bme lab. Francis turbine has two cases, in initial one straightforward francis turbine i. It was designed by american scientist james francis. Impulse turbine and reaction turbineprinciple, working and. A francis turbine is a type of reaction turbine used most frequently in medium or largescale hydroelectric plants. In kaplan and propeller shaft turbines axial flow runner is used where as in francis turbine radial flow runner in use.

Design optimization method for francis turbine h kawajiri, y enomoto and s kurosawaexperimental and numerical investigation of unsteady behavior of cavitating vortices in draft tube of low specific speed francis turbine y tamura, k tani and n okamotorecent citations solving the runner blade crack problem for a francis hydro turbine operating. The water enters the runner with a low velocity but with a considerable pressure. Examples losses in francis turbines npsh main dimensions. In the case of reaction turbine, the moving blades of a turbine are shaped in such a way that the steam expands and drops in pressure as it passes through them. The principal feature of a reaction turbine that distinguishes it from an impulse turbine is that only a part of the total head available at the inlet to the turbine is converted to velocity head, before the runner is reached. Design and analysis of a kaplan turbine runner wheel. The upper part of the blades use the reaction force of water flowing through it. Our francis turbines, including the worlds largest and most powerful.

As a result of pressure decrease in the moving blade, a reaction force will be produced. Introduction to francis turbine the francis turbine is a mixed flow reaction turbine. Working of francis turbine is explained in this video in a step by step logical manner, with help of animation. A reaction turbine has rows of fixed blades alternating with rows of moving blades. Jul 24, 20 working of francis turbine is explained in this video in a step by step logical manner, with help of animation. Its complex parameters cause direct effect on the global parameters which change the efficiency and the output power. Functions of spiral casing, guide vanes, runner blades, blade pitching and draft tube. In axial flow turbines, the water flows through the runner along the direction parallel to the axis of rotation of the runner. The runner is keyed to the shaft which is coupled to the generator shaft.

The francis turbine is also called a radial flow turbine, since water flows from the outer circumference towards the centre of runner. The purpose of this study is the investigation of the effects of theoretical turbine runner parameters. Kaplan turbine works on the principle of axial flow reaction. Francis turbine working principle, main parts, diagram and. Francis turbines are the most common water turbine in use today. So selection of type of runners is depends only on the type of turbines. Pdf theoretical analysis of turbines for predicting of operating. A water turbine is a rotary machine that converts kinetic energy and potential energy of water into mechanical work water turbines were developed in the 19th century and were widely used for industrial power prior to electrical grids. The opening between the vanes can be adjusted to vary the quantity of water admitted to the turbine. The difference in the operating head can be extra simply controlled in francis turbine than in the pelton wheel turbine. In this study, an existing runner of a francis turbine of 250mw hydro power plant is considered.

Turbine machines are pumps, fans, compressors, water turbines, gas turbines, steam turbines, wind turbines, aircraft and marine propellers, torque converters, hydrodynamic clutches etc. It is well suited for operating under high heads the turbine capable of working under the high potential head of water is the pelton wheel turbine which works on the head greater. Guide vanes are housed in a spiral casing called as volute. Kaplan turbine spiral casing runner guide vanes stay vanes draft tube cone. The water at the inlet of the turbine possesses both kinetic energy as well as pressure energy for effective rotation the blades in a hydropower station. The water is admitted to the runner through guide vanes or wicket gates. The working principle of this turbine is same as other impulse water turbines. Francis turbine its components, working and application. For the carrying out of certain efficiencies with high values throughout the entire guaranteed functionary domain, the turbine is provided with a double. Then enters the moving blades where its direction of flow is changed thus producing an impulse force on the moving blades. Mathematical modeling for the design of francis runner. The turbine is located between the highpressure water source and the lowpressure water exit, usually at the base of a. The variation in the operating head is difficult to control because of high heads. Pdf parametrical and theoretical design of a francis.

Jan 23, 2018 francis turbine blades are designed in such a way that one portion of the blade design creates the pressure difference between the opposite faces of the blade when water flows through it, and the remaining portions blade design use the impulse force of water hitting it and this combined action of pressure difference and impulse force. Design optimization of a high specific speed francis turbine. Such high head runners, put in operation in 1950, hve been in operation in. Now they are mostly used for electric power generation. The sprinter of the francis turbine is comprised of cast press, cast steel and tempered steel. Dimensions of the outlet g a u b u g u b g c npsh a m r.