PDF
Full
Outline
For the pressurized water supply project of a long distance, large flow and high lift pumping station, the pump trip was simulated. Combined with the characteristics of the engineering terrain, the combined protection method of air-cushion surge chamber and one-way surge tank was proposed. And then the sensitivity analysis of the closing rule of the valve after the pump and the throttle orifice of the surge chamber was carried out according to the requirements of pipeline pressure control. The results show that the air cushion surge chamber could effectively protect the water hammer of the pump trip and the water hammer of valve shutdown caused by the rapid closure of the pump valve. The one-way surge tank solved the problem of local high pressure caused by the continuous water refill of the air cushion surge chamber, and protected the safety of the high point pipe section. The combined protection scheme could significantly reduce the volume of air cushion surge chamber and saved the engineering cost. In addition, the closing rule of the pump valve and the throttle orifice area of the air cushion surge chamber has a great impact on the water hammer pressure of the pipeline. Too fast valve closing or too large throttle orifice area will lead to the positive pressure of the pipeline exceeding the standard. Too slow valve closing or too small throttle orifice area will lead to large negative pressure in the pipeline. The specific project needs to be optimized in combination with transition process simulation. For this project, after simulation and optimization, the diameter of the throttle orifice was 0.8m, and the valve of the pump was closed by 5s straight line, and the results met the requirements of regulation guarantee calculation.
PDF
89
12
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |
关闭全屏
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
