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42-678: The project consisted of the construction of two main dams, the Mangla Dam built on the Jhelum River and the Tarbela Dam constructed on the Indus River, together with their subsidiary dams. This article about a dam or floodgate in Pakistan is a stub . You can help Misplaced Pages by expanding it . Mangla Dam The Mangla Dam ( Urdu : منگلا بند ) is a multipurpose dam situated on

84-458: A cost of Rs . 101.384 billion. This project effectively raised the dam height by 30 feet to 482 feet (147 m), thereby raising the maximum water conservation level from 1202 feet to 1242 feet. This increased the dam's storage capacity from 5.56 to 9.12 billion m (4.51 to 7.39 million acre⋅ft). Besides, it is expected that after raising the height of the Mangla Dam by 30 feet,

126-442: A make of Škoda , Czech Republic and were commissioned in 1994. These turbines are connected to umbrella-type generators which have a generation capacity of 100 MW. Hitachi , Japan had provided generators for turbines 1–4 and 7-8 while Škoda generators are connected to turbines 5-6 and 9–10. These generators are in turn connected to three-phase transformers. The transformers connected to turbines 1, 4, and 7 were manufactured by

168-505: A new turbine design. Francis turbines are primarily used for producing electricity. The power output of the electric generators generally ranges from just a few kilowatts up to 1000 MW, though mini-hydro installations may be lower. The best performance is seen when the head height is between 100–300 metres (330–980 ft). Penstock diameters are between 1 and 10 m (3.3 and 32.8 ft). The speeds of different turbine units range from 70 to 1000  rpm . A wicket gate around

210-488: A small dam called Jari Dam to block the Jari Nala ;– about 11 miles (18 km) beyond the new Mirpur town had to be constructed. There was a total of 120 x 10 cubic yards (cu yds) of excavation for the reservoir whereas the total fill amounted to 142 x 10 cu yds and concrete to 1.96 x 10 cu yds respectively. The main embankment is earthfill with clay as the core material. Gravel and A-type sandstone are applied on

252-436: A wide range of heads and flows. This versatility, along with their high efficiency, has made them the most widely used turbine in the world. Francis type units cover a head range from 40 to 600 m (130 to 2,000 ft), and their connected generator output power varies from just a few kilowatts up to 1000 MW. Large Francis turbines are individually designed for each site to operate with the given water flow and water head at

294-617: Is 274 ft (84 m) and the length is 6,800 ft (2,100 m). The main spillway is a submerged orifice type with 9 radial gates, 36 ft (11 m) x 40 ft (12 m) each; it has a maximum capacity of 1.1 million cusecs. The emergency spillway is a weir type with an erodible bund and a maximum capacity of 0.23 million cusecs. The 5 tunnels are steel and concrete lined and 1,560 feet long in bedrock. The internal diameter ranges between 26 ft (7.9 m) and 31 ft (9.4 m). The powerhouse, which consists of turbines, generators, and transformers, has been constructed at

336-508: Is a type of water turbine . It is an inward-flow reaction turbine that combines radial and axial flow concepts. Francis turbines are the most common water turbine in use today, and can achieve over 95% efficiency. The process of arriving at the modern Francis runner design took from 1848 to approximately 1920. It became known as the Francis turbine around 1920, being named after British-American engineer James B. Francis who in 1848 created

378-404: Is a type of reaction turbine, a category of turbine in which the working fluid comes to the turbine under immense pressure and the energy is extracted by the turbine blades from the working fluid. A part of the energy is given up by the fluid because of pressure changes occurring on the blades of the turbine, quantified by the expression of degree of reaction , while the remaining part of the energy

420-413: Is earthfill with B-type sandstone as the core material. A-type sandstone is applied on the shoulders. The maximum height of the intake embankment above the core trench is 144 ft (44 m) and the length is 16,900 ft (5,200 m). Jari Dam is also an earthfill type with silt as the core material. Gravel is applied on the shoulders of the dam. The maximum height of Jari dam above the core trench

462-472: Is equal to that at the inlet to the draft tube. Using the Euler turbine equation, E / m = e = V w1 U 1 , where e is the energy transfer to the rotor per unit mass of the fluid. From the inlet velocity triangle, and Therefore The loss of kinetic energy per unit mass at the outlet is V f2 /2 . Therefore, neglecting friction, the blade efficiency becomes i.e. Degree of reaction can be defined as

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504-445: Is extracted by the volute casing of the turbine. At the exit, water acts on the spinning cup-shaped runner features, leaving at low velocity and low swirl with very little kinetic or potential energy left. The turbine's exit tube is shaped to help decelerate the water flow and recover the pressure. Usually the flow velocity (velocity perpendicular to the tangential direction) remains constant throughout, i.e. V f1 = V f2 and

546-547: Is greater in northern cities and towns. In Bradford , an industrial town in north-west England , it is estimated that roughly three-quarters of the population is from Mirpur, with a sizeable population also in Birmingham. At the time, many took up work in the textile and steel mills, due to the acute shortage of workers in England. The project was designed primarily to increase the amount of water that could be used for irrigation from

588-455: Is necessary, as these are major parameters affecting power production. Draft tube : The draft tube is a conduit that connects the runner exit to the tail race where the water is discharged from the turbine. Its primary function is to reduce the velocity of discharged water to minimize the loss of kinetic energy at the outlet. This permits the turbine to be set above the tail water without appreciable drop of available head. The Francis turbine

630-520: Is still increasing." Mangla reservoir had an initial reservoir capacity of 7.25  billion cubic metres (5.88 million acre-feet ), which reduced to 5.77 billion m (4.674 million acre⋅ft) in 2005 due to the sedimentation & was likely to reduce further. To counteract this phenomenon, the Mangla Dam Raising Project was started in 2004 and the main dam, spillway and its allied works were completed in 2009 at

672-527: The Indian Air Force during the Indo-Pakistani War of 1971 . This was against the international convention that large water reservoirs would not be targeted in war. As a consequence, the hydro project was temporarily out of service. From the data available in 2009, the project had generated 183.551 billion units of low-cost Hydel energy since its commissioning. The annual generation during 2008-2009

714-476: The Jhelum River and Poonch River in the Mirpur District of Kashmir , about 108 kilometres (67 mi) southeast of the capital city of Islamabad . The Mangla Dam components include a reservoir, main embankment, intake embankment, main spillway, emergency spillway, intake structures, 5 tunnels, and a power station. Besides the main dam, a dyke called Sukian – 17,000 ft (5,200 m) in length and

756-520: The Jhelum River , lying in the Mirpur District of Azad Kashmir and the Jhelum District in Punjab , Pakistan . It is the sixth-largest dam in the world. The village of Mangla , which sits at the mouth of the dam, serves as its namesake. In November 1961, the project's selected contractors were revealed; it was announced that Binnie & Partners, a British engineering firm, was going to serve as

798-530: The Italy-based Savigliano. The transformers for turbine 5 and 6 are a make of Italtrafo , another Italian company, while the remaining five transformers were provided by Škoda. The Government of Pakistan had agreed to pay royalties to the Government of AJK (Azad Jammu and Kashmir) for the use of the water and electricity generated by the dam. Pakistan initially committed to supplying free electricity to

840-521: The Mangla Dam powerhouse which is estimated to provide additional production for the next 40 years. The project, when complete, will increase the power generation capacity of the Mangla Dam to 1,310 MW from the existing 1,000 MW capacity. WAPDA successfully commissioned two refurbished generating units of the Mangla Hydel Power Station on 23 May 2022, increasing their capacity from 200 MW to 270 MW. Francis turbine The Francis turbine

882-532: The Mirpur Bypass and two bridges across River Jehlum and Bong Canal respectively. The dam was expanded in the era of Pervez Musharraf but it did not enhance the capacity of electric generation except increasing the level of water in the dam. In November 2012, the United States announced a grant of $ 150 million for the expansion of the Mangla Dam powerhouse. Under the project, $ 400 million would be spent on

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924-764: The area as a result of the dam being built. Some of those affected by the dam were given work permits for Britain by the Government of Pakistan, and as a result, in many cities in the UK the majority of the Pakistani community originates from the Dadyal-Mirpur area of Kashmir . There are 747,000 Mirpuris in the United Kingdom, and the British Mirpuri community forms about 70% of the British Pakistani community. The percentage

966-406: The design of high-efficiency turbines to precisely match a site's water flow and pressure ( water head ). A Francis turbine consists of the following main parts: Spiral casing : The spiral casing around the runner of the turbine is known as the volute casing or scroll case. Throughout its length, it has numerous openings at regular intervals to allow the working fluid to impinge on the blades of

1008-545: The entire region of Azad Kashmir and providing complimentary clean water to the city of Mirpur. However, over time, this agreement was not transparently upheld, resulting in Pakistan encountering challenges in fulfilling its financial obligations related to royalty payments for electricity and water services in Azad Kashmir. Over 280 villages and the towns of Mirpur and Dadyal were submerged and over 110,000 people were displaced from

1050-450: The flow of the Jhelum and its tributaries. Its secondary function was to generate electrical power from the irrigation releases at the artificial head of the reservoir. The project, though not initially designed as one, also works as a flood control structure by retaining water during the flood-prone season of Monsoon . On 5 December 1971, the dam was damaged due to a bombing raid conducted by

1092-436: The guide and stay vanes is to convert the pressure energy of the fluid into kinetic energy. It also serves to direct the flow at design angles to the runner blades. Runner blades : Runner blades are the heart of any turbine. These are the centers where the fluid strikes and the tangential force of the impact produces torque causing the shaft of the turbine to rotate. Close attention to design of blade angles at inlet and outlet

1134-456: The highest possible efficiency, typically over 90% (to 99% ). In contrast to the Pelton turbine , the Francis turbine operates at its best completely filled with water at all times. The turbine and the outlet channel may be placed lower than the lake or sea level outside, reducing the tendency for cavitation . In addition to electrical production , they may also be used for pumped storage , where

1176-623: The irrigation system of the country as part of the Indus Basin Project , with the other being the Tarbela Dam situated on the Indus River in Swabi , Khyber Pakhtunkhwa . The Mangla Dam was constructed at a cost of ₨ 1,558.7 billion ( US$ 14.73 billion) with funding being provided by the World Bank and the Asian Development Bank . The dam was constructed between 1961 and 1965 across

1218-642: The lead designers, engineers, and inspectors for the construction of the dam (led by Geoffrey Binnie ). The project was undertaken by a consortium known as the Mangla Dam Contractors, which consisted of eight American construction firms sponsored by the Guy F. Atkinson Company based in South San Francisco , California . As part of the Indus Waters Treaty signed in 1960, India gained rights to

1260-607: The outside of the turbine's rotating runner controls the rate of water flow through the turbine for different power production rates. Francis turbines are usually mounted with a vertical shaft, to isolate water from the generator. This also facilitates installation and maintenance. Water wheels of different types have been used for more than 1,000 years to power mills of all types, but they were relatively inefficient. Nineteenth-century efficiency improvements of water turbines allowed them to replace nearly all water wheel applications and compete with steam engines wherever water power

1302-481: The power house will generate 12 percent additional energy per year which will increase its installed capacity from 1,000 MW to 1,120 MW. The Mangla Dam Raising Project, however, has affected more than 40,000 people living in the vicinity of the dam. The total cost of compensation and resettlement was Rs. 70 billion. The resettlement project includes the construction of New Mirpur City , four satellite towns (Islamgarh, Chakswari, Dadyal, Siakh) with all civic amenities,

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1344-481: The powerhouse. Each of these turbines has an output of 138,00 bhp with a rated head of 295 feet of water. The first four turbines were manufactured by Mitsubishi Electric , Japan and were installed in 1969, turbines 5 and 6 are manufactured by ČKD Blansko , the Czech Republic and were installed in 1974, turbines 7-8 were manufactured by ACEC , Belgium and were installed in 1981, while the remaining two turbines are

1386-433: The ratio of pressure energy change in the blades to total energy change of the fluid. This means that it is a ratio indicating the fraction of total change in fluid pressure energy occurring in the blades of the turbine. The rest of the changes occur in the stator blades of the turbines and the volute casing as it has a varying cross-sectional area. For example, if the degree of reaction is given as 50%, that means that half of

1428-400: The runner. These openings convert the pressure energy of the fluid into kinetic energy just before the fluid impinges on the blades. This maintains a constant velocity despite the fact that numerous openings have been provided for the fluid to enter the blades, as the cross-sectional area of this casing decreases uniformly along the circumference. Guide and stay vanes : The primary function of

1470-602: The same principles. S. B. Howd obtained a US patent in 1838 for a similar design. In 1848 James B. Francis , while working as head engineer of the Locks and Canals company in the water wheel-powered textile factory city of Lowell, Massachusetts , improved on these designs to create more efficient turbines. He applied scientific principles and testing methods to produce a very efficient turbine design. More importantly, his mathematical and graphical calculation methods improved turbine design and engineering. His analytical methods allowed

1512-417: The shoulders. The maximum height of embankment above the core trench is 454 ft (138 m) and the length is 8,400 ft (2,600 m). The intake embankment is earthfill type with B-type sandstone as the core material. Gravel is applied on the shoulders. The maximum height of the intake embankment above the core trench is 262 ft (80 m) and the length is 1,900 ft (580 m). Sukian Dam

1554-567: The toe of an intake embankment at the ground surface elevation of 865  feet SPD. The water to the powerhouse is supplied through five steel-lined tunnels of 30/26 feet diameter. Each tunnel is designed to feed two generating units. The powerhouse tailrace discharges into New Bong Canal, which has a length of 25,000  feet with a discharge capacity of about 49,000 cusecs, and terminates at an automatic gate control headworks at about 12 km downstream located near old Bong Escape Headworks. There are ten vertical Francis type turbines in

1596-876: The total energy change of the fluid is taking place in the rotor blades and the other half is occurring in the stator blades. If the degree of reaction is zero it means that the energy changes due to the rotor blades is zero, leading to a different turbine design called the Pelton Turbine . The second equality above holds, since discharge is radial in a Francis turbine. Now, putting in the value of 'e' from above and using V 1 2 − V f 2 2 = V f 1 2 cot ⁡ α 2 {\displaystyle V_{1}^{2}-V_{f2}^{2}=V_{f1}^{2}\cot \alpha _{2}} (as V f 2 = V f 1 {\displaystyle V_{f2}=V_{f1}} ) Francis turbines may be designed for

1638-542: The waters of the Ravi , Sutlej and Beas rivers, while Pakistan , in addition to the waters of the aforementioned three rivers' sections within Pakistani territory and some monetary compensation, received the rights to develop the Jhelum , Chenab and Indus river basins. Until 1967, the entire irrigation system of Pakistan was fully dependent on unregulated flows of the Indus River and its major tributaries . The agricultural yield

1680-403: Was 4797.425 Million KWh while the station shared a peak load of 1150 MW which was 8.18% of the total WAPDA system peak. On 1 September 2013, the water level in Mangla Dam reached a record height of 1237.15 feet against the maximum conservation level of 1242 feet. Radio Pakistan reported that "the water level in Mangla Dam has attained the maximum height of 1237.15 feet in the history and it

1722-516: Was available. After electric generators were developed in the late 1800s, turbines were a natural source of generator power where potential hydropower sources existed. In 1826 the French engineer Benoit Fourneyron developed a high-efficiency (80%) outward-flow water turbine. Water was directed tangentially through the turbine runner, causing it to spin. Another French engineer, Jean-Victor Poncelet , designed an inward-flow turbine in about 1820 that used

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1764-428: Was very low for a number of reasons, the most significant being a lack of water during critical growing periods. This problem stemmed from the seasonal variations in river flow due to monsoons and the absence of storage reservoirs to conserve the vast amounts of surplus water during those periods of high river discharge. The Mangla Dam was the first of the two dams constructed to reduce this shortcoming and strengthen

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