ANALYSIS OF STUDIES ON THE WATER SUPPLY DEPARTMENT OF IRRIGATION PUMPING STATIONS

ABSTRACT

The article presents the results of a study conducted by researchers to improve the size of water intake units to study the hydraulic operation of the pumping station avancameras, to improve the operation of water intake units, to develop pumping units at full capacity and deliver the specified amount of water to the field.

АННОТАЦИЯ

В статье представлены результаты исследования, проведенного исследователями по усовершенствованию габаритов водозаборных агрегатов для изучения гидравлической работы насосной станции аванкамеры, по совершенствованию работы водозаборных агрегатов, по выработке насосных агрегатов на полную мощность и выдаче заданного количество воды на поле.

Keywords: pump, pump unit, pump station, sediment, water supply, water intake structure, hydraulic resistance, flow, turbidity, avankamera, pressure, resistance coefficient.

Ключевые слова: насос, насосный агрегат, насосная станция, отстой, водоснабжение, водозаборное сооружение, гидравлическое сопротивление, расход, мутность, аванкамера, напор, коэффициент сопротивления.

In our country, the design of water intake units of pumping stations has long been engaged. A lot of experimental research has been done on this. Simultaneously with the experimental studies, they were generalized and recommendations were developed, for example, in the manual "Guidelines for the design of pumping stations at irrigation facilities" developed by the Institute of Water Resources Design under the Ministry of Water Resources. based on the results of the research. 

Improving the efficiency of irrigation pumping stations, improving the design of its equipment and facilities, as well as studying the local conditions and factors that affect the efficiency of the machine-lifting complex, and the establishment of a system of research and production.

In order to obtain data on the impact of the decline in the performance of pumping units, a number of pumping stations in our region were surveyed.

An analysis of the operating conditions of many pumping stations shows that due to the lack or non-availability of water flow measuring equipment, service personnel are using the indicators listed in the passport of the pumping units. The inability to control the performance of the pump causes problems in linking its characteristics (water lift, pressure, coefficient of performance).

One of the main problems in machine irrigation of agricultural crops is the peculiarity of the rivers of Central Asia, ie the high level of turbidity. For example, according to the Tashkent Institute of Irrigation and Land Reclamation (TIMI), the average annual turbidity in the main water sources of the region is 5-7 kg / m3, and the average monthly turbidity is 10-12 kg. / m3. Almost all the particles that make up the turbid composition are smaller than 0.25 mm, and 40-60% of them are particles with a diameter of 0.01 mm. 50-60% of the particles in the mud are particles with a hardness of 5 or more on the Mos scale. [2]

According to the current design of the pumping stations, a certain amount of runoff in the water should be trapped in the sediments and the rest should reach the fields by irrigation networks. Working in such conditions requires taking into account the design of the pumps, as well as the turbidity of the water when choosing the mode of operation.

The research is mainly aimed at studying the impact of the design of water intake units and hydraulic flow regime on the hydromechanical and power equipment of the pumping station, i.e. the dimensions of the water intake unit, the minimum value of hydraulic losses at the inlet to the suction pipe. At the same time, the operation of the pump is affected not only by the size of the water intake unit and its shape, but also by the distribution of flow along the front of the water intake structure, the different flow of water to each water intake unit. Below is a brief analysis of some of the scientific papers.

 Professor M.Ya. Chernishov proposed a method based on the method of calculating the water intake chamber of straight-axis tubular pipe devices in determining the shape of the water intake unit of the pump. This method is based on the condition of impact, ie the speed of water entering the compartment and the speed of entry into the suction pipe must be equal to each other. [1].

To meet this condition, the surface area or gap between the edge of the inlet of the suction pipe and the bottom of the compartment must be equal to the surface of the inlet of the pipe..

Here, the height of the shaft h₁= 0,25D_кир  in practice, this height is set to 0.4D_кир, taking into account the compression of the current at the input..

In order to prevent the formation of floating funnels, M.Ya. Chernishev recommends that the inlet of the suction pipe be taken at a distance of not less than 0.4 ÷ 0.5 m from the water level h₁.

In the movement of the flow in the water intake unit, AI Krasnoyurchenko performed a number of comparative experiments, in which he studied the problems of obtaining water from chambers of different shapes (appearances) in the plan with a propeller reading pump. The suction line of the propeller pump is equipped with a specially designed guide apparatus, and water is brought to the pump from the side. It was possible to change the size of the camera in horizontal and vertical directions. As a result of his research, A.I.Krasnoyurchenko came to the following conclusions:

The optimum distance from the bottom of the water intake unit to the inlet of the suction pipe is h₁= 0.8 D_кир

Convenient depth of water in the water intake unit h_кам= (2÷2.5) D_кир

The width of the water intake compartment в_бул and its length L_бул should not be less than 4D_кир .

The water exchange coefficient should be around   = (9÷10).

In short, one of the ways to increase the efficiency of pumping stations is to improve the operational quality of the units used by them, which in turn leads to a reduction in the cost of pumped water. Operational measures should be aimed at reducing the cost of pumped water, as the issue of cost is one of the main indicators of the pumping station. It is therefore of interest to determine the composition of the factors influencing the pumping of the water. Improving the efficiency of the pumping station will be possible only if it regularly conducts scientific and production work to improve the design of equipment and facilities, the study of local conditions and factors that affect the efficiency of the whole complex.

References:

1. Mamajanov M. Analiz ekspluatatsionnыx usloviy rabotы nasosnыx stansiy selskoxozyaystvennogo naznacheniya. Vestnik agrarnoy nauki Uzbekistana. T. 2004 g.
2. Xoxlov V.A. Energosberegayuщiye rejimы rabotы nasosov i nasosnыx stansiy s dlinnыmi truboprovodami: Avtoref. dis. dokt. texn. nauk. Tashkent. IEA. 2009 g.
3. Mamajonov M. Gidroabrazivnыy  iznos elementov  protochnoy chasti tsentrobejnыx i osevыx nasosov.// Nauch.-texn. j. FerPI.- Fer­gana. 2003 g.
4. Lomakin A.A. Sentrobejnыe i osevыe nasosы.- M.- L.: Mashinostroyeniye. 1966 g.
5. Dilmrod X. et al. IMPROVING THE OPERATION RELIABILITY OF THE COMPLEX OF CONSTRUCTIONS OF THE KUYGANOR HYDRAULIC UNIT //Universum: технические науки. – 2021. – №. 10-5 (91). – С. 52-55.
6. МАМАЖОНОВ М. М., ШАКИРОВ Б. М., ШЕРМАТОВ Р. Ю. Конструктивные решения по улучшению гидравлических условий работы водоприемных камер насосных станций //Российский электронный научный журнал. – 2015. – №. 2. – С. 21-27.
7. Шерматов Р. Ю. и др. ОБЕСПЕЧЕНИЕ БЕЗОПАСНОСТИ УЧКУРГАНСКОГО ГИДРОУЗЛА НА РЕКЕ НАРЫН //Главный редактор: Ахметов Сайранбек Махсутович, д-р техн. наук; Заместитель главного редактора: Ахмеднабиев Расул Магомедович, канд. техн. наук; Члены редакционной коллегии. – 2021. – С. 25.
8. Мамажонов М. и др. ЭКОНОМИЧЕСКИЕ ПОКАЗАТЕЛИ РЕКОМЕНДАЦИЙ ПО ПОВЫШЕНИЮ ЭФФЕКТИВНОСТИ НАСОСНЫХ СТАНЦИЙ //Научно-практические пути повышения экологической устойчивости и социально-экономическое обеспечение сельскохозяйственного производства. – 2017. – С. 1011-1016.