Summary of cognitive practice

In the hot summer and scorching sun, it is not easy to experience life in seclusion in an era when you can be sprayed by a network sprayer if you eat a bowl of noodles incorrectly! So thank you very much for giving me this internship opportunity.

At eleven o'clock on July 3rd, we set off by bus on time. I was dumbfounded by the four seasons changes caused by the altitude difference. Six hours' drive, we came to Panzhihua, where even an old cow can stick out its tongue.

The next day, we visited Ertan Hydropower Station, where there is the highest hyperbolic arch dam in China in the 20th century, and there is a power generation hero who can spit out more than 100 billion kwh of electricity a year in the deep mountains and forests. I was shocked to see this. Huge projects can even bring more power than huge ones, but workers are very busy and will leave in a hurry after being shocked.

After leaving Panzhihua, we went to Xichang to see the legendary Guandi Datou Dam. The environment in Xichang is much better than that in Panzhihua, and the city has become prosperous and not so hot. Maybe the altitude is higher or Qionghai has obvious effect on climate regulation and storage.

Guandi Hydropower Station is still on the Yalong River. This hydropower station is a little smaller than Ertan. It has four generator sets, but the annual power generation can also reach 654.38+0.4 billion kWh. However, the dam of this hydropower station is a big head dam. We can clearly see the structure and overall layout of Datouba, and our understanding of Datouba is not limited to textbooks.

On the fourth and last day, the pleasant trip was over. After a long-distance attack of 12 hours, we returned to Kunming.

This internship helped me a lot, and let us have a fuller understanding of many things. Next, I will come one by one.

Ertan hydropower station

We arrived at Ertan on the morning of July 4th. According to the previous data, Ertan Hydropower Station is located at the junction of Yanbian County and Miyi County, Panzhihua City, southwestern Sichuan Province, China, in the lower reaches of Yalong River, with the dam site 33km away from the intersection of Yalong River and Jinsha River and 46km away from Panzhihua City. It is the first hydropower station developed in cascade in Yalong River Hydropower Base, and Guandi Hydropower Station is upstream.

Through the explanation of the worker's master, we learned that the maximum dam height of the hydropower station is 240 meters, the normal water level of the reservoir is 1200m, the total storage capacity is 5.8 billion cubic meters, the regulated storage capacity is 3.37 billion cubic meters, the total installed capacity is 3.3 million kilowatts, the guaranteed output is/kloc-0.00 million kilowatts, and the average power generation for many years is/kloc-0.20-/kloc-.

The hydropower station started in September 199 1 year, and the first generating unit was generated in July198, which was completed in 2000. It is the largest power station built and put into operation in China in the 20th century.

Ertan Lake of Ertan Hydropower Station is located in Yanbian County, the first county in Panzhihua City, Sichuan Province, above the lower reaches of Yalong River. It is an important scenic spot and part of Ertan National Forest Park, an artificial lake formed by Ertan Hydropower Station, and an important water conservation area of Shangri-La Ecological Circle in Sichuan and Yunnan.

The dam of the hydropower station is a hyperbolic arch dam that blocks the river. In fact, we all know why hyperbolic arch dams should be built. Because the Yalong River is located in the V-shaped valley where the Yunnan-Guizhou Plateau and the Qinghai-Tibet Plateau meet, the mountains and waters are long and the standards on both sides of the strait are high, so it can bear a great impact. It is the most reasonable to build an arch dam. Because the navigation of Yalong River is different and fish is not a precious species, there are no navigation structure and fishery buildings such as ship lifts and ship locks.

The energy dissipation measure of dam flood discharge is to pick up the current to dissipate energy. By designing the direction of the spillway surface hole, the water flow collides in the air to reduce the energy of the water flow. The spillway surface hole is located in the center of the arch dam crest, with a total of 7 holes, each with a width of 1 1 m, a height of1.5 m and a weir crest elevation of1. Using adjacent large drop 30 and 20 depression angle sill discharge holes ***6 holes, arranged on the arch dam. In order to make the water tongue have a larger collision angle with the water tongue of the face, the shape of the middle hole is upturned. The outlet elevation is 1 120m, and the orifice section is square, with a size of 6m× 5m. In order to avoid the radial concentration of water flow, the middle hole is deflected by pressure on the plane, and the water jets are dispersed in the horizontal and vertical directions at three different angles of 30,17 and10, so as to avoid the overlapping of water jets and deepen the downstream scouring.

In terms of flood discharge, hydropower stations also have flood discharge tunnels. Two flood discharge tunnels are arranged on the right bank, which are arranged in a straight line, and the water intake is short. The tunnel is an open-flow tunnel with a square cross section and a size of 13m× 13.5m (width× height). The elevation of the entrance bottom is 1 163m. 1 The length of the No.2 cave is 1 197.33 meters. The straight slopes and bottom slopes of the two tunnels are 7.9% and 7% respectively. The concentrated drop of Longtaitou section is 70 meters, and the maximum speed in the tunnel is about 45 meters per second. In order to prevent cavitation damage of high-speed water flow, five aeration facilities and seven aeration facilities were set in these two flood discharge tunnels respectively. Aeration equipment is a new type of U-shaped trough bucket aeration equipment. The discharge capacity of the three sets of flood discharge facilities can independently discharge the floods encountered all the year round. During the flood, three sets of flood discharge facilities jointly discharge flood, and the surface hole and the middle hole collide up and down to disperse energy dissipation.

At the same time, we know that Ertan Hydropower Station is the largest hydropower station in the 20th century, with great difficulty in design and construction and high technology content. The total approved quantities are: 8147,200 cubic meters of earth and stone excavation, 3,368,300 cubic meters of earth and stone excavation, 654,380+0.4 million cubic meters of earth and stone filling and 5.98 million cubic meters of concrete. The installation of metal structure is 6.5438+0.9 million tons. Construction diversion is carried out in two stages. In the first phase, tunnel diversion is adopted, riverbed cofferdam is intercepted once, and construction is carried out all the year round. The diversion standard is once every 30 years, and the flood flow is13500m3 per second. In the second stage, the bottom hole of the dam is used for diversion, and the standard is1October 10 to April 10 of the following year, with a flow rate of1500m3/s. Two diversion tunnels are located on both banks with a cross-sectional area of17. The lengths of the left and right diversion tunnels are1089.75m and165,438+067.08m, respectively, and the entrance elevation is1065,438+00m.

The success of Ertan Project marks a new level of hydropower construction in China, which makes Sichuan and Chongqing bid farewell to the power shortage for many years and lays the foundation for economic development in the next century.

After two hours' visit, the workers told us a lot and gained a lot. They reluctantly left Ertan and went to the next stop, Guandi Hydropower Station!

Guandi hydropower station

Guandi Hydropower Station is located in the upper reaches of Ertan, on the Yalong River and on the Jinsha River at the junction of Xichang and Yanyuan County. It belongs to one of the five cascade hydropower stations in the lower reaches of Yalong River.

Compared with Ertan, Guandi Hydropower Station is a little smaller. Official land has no other agricultural storage function, only one function of power generation. It is one of the main power supply points of Yalong River Hydropower Base. The total installed capacity of the power station is 2.4 million kilowatts (4× 600,000 kilowatts), the average power generation for many years is about 65.438+065.438+87 million kWh, and the static investment of the project is 65.438+029. The normal water level of the reservoir is1330m, with a total storage capacity of 760 million cubic meters, and the backwater of the reservoir is as long as 58km. It operates jointly with the upstream reservoir and has annual regulation performance. Yalong River Hydropower Base is one of the thirteen hydropower bases planned by the state, and the resources of the thirteen hydropower bases exceed half of the whole country. The construction of the base occupies an important position in hydropower construction and is a landmark project of the western development. The proposal of thirteen hydropower bases has greatly promoted the cascade development of river basins, the optimal allocation of resources and the economic development of western China.

The river dam of Guandi Hydropower Station is a gravity dam, which is also known as the so-called big head dam. But seeing is believing, and seeing it is even more shocking.

The controlled watershed area above the dam site of Guandi Reservoir is1117 square kilometers, and the annual average flow is 1430 cubic meters per second. The normal water level is1.330m, the total storage capacity is 760 million cubic meters, and the backwater of the reservoir is 58km long. It operates jointly with the upstream reservoir and has annual regulation performance. The dam is a roller compacted concrete gravity dam, with the crest elevation 1334m and the maximum dam height 168m.

The dam adopts underflow energy dissipation facilities. This time, we went to the top of the weir to observe it closely. The working principle of underflow energy dissipation is to set stilling basin and stilling sill downstream of the dam site to make the water flow jump in a limited range. Through the internal friction, aeration and impact consumption of water flow, standing on the stilling basin at the top of the dam, the stilling sill can be seen in a glance!

The basin area of the reservoir controlled by such a large dam is1117 square kilometers, and the average flow for many years is 1430 cubic meters per second. The normal water level is1.330m, the total storage capacity is 760 million cubic meters, and the backwater of the reservoir is 58km long. It operates jointly with the upstream reservoir and has annual regulation performance.

According to the worker's master, this hydropower station has good economic benefits, good topographic and geological conditions, relatively convenient transportation, small reservoir flooding loss, small number of immigrants and superior economic and technical indicators. The static investment per kilowatt is 54 12 yuan, and the static investment per kilowatt is 1. 18 yuan. The comprehensive benefits are remarkable. It can transmit1177.6 billion kwh of clean and high-quality electric energy to Sichuan-Chongqing power grid and East China power grid every year, and it is the backbone power supply point for power transmission from west to east. It is another compensation power station after Jinping I Hydropower Station and has obvious cascade compensation benefits. In addition, after the completion of Guandi Hydropower Station, not only the cascade compensation benefit is obvious, but also the power quality is excellent when it is jointly operated with the upstream reservoir power station. Its construction is of great strategic significance for speeding up the development of Yalong River, optimizing the structure of Sichuan power grid and improving the transmission capacity of Sichuan power grid.

Through this internship, I have a deeper understanding of hydropower stations. The heavy equipment in these countries is made by generations of builders. They have accumulated one experience after another for our hydropower construction, which is a monument in the growth history of China. The safe and stable operation of the same unit has written an immortal poem about the conscientious work of every employee and the hard work of the officers and men of the armed police to defend the hydropower station!

Although China's hydropower has been ranked first in the world, there are still many problems to be solved! For example, crossing the Fish House should not only make everyone have enough electricity, but also rationally develop hydropower without destroying the ecology. Therefore, we should study hard, master theory and professional knowledge, break through the unknown areas and make contributions to the cause of the motherland!