AIR CHAMBER AS WATER SHOCK ABSORBER

Аннотация

The article is devoted to the study of a water shock absorber - an air chamber, used in long pressure systems and in pressure pipelines of pumping stations. The work provides an analysis of scientific works. The efficiency of pressure pipelines depends on ensuring their trouble-free operation - the reliability of pressure hydraulic systems. The reliability of long pressure pipelines is ensured using theproposed design ofa water shock damper. As a result of a joint solution of the equation of unsteady pressure motion of the liquid, the equation of flow continuity and the equation of the state of air in the chamber, dependencies were obtained for calculating the volume of the proposed absorber, taking into account the isothermal and adiabatic laws ofair compression. To check the reliability of the obtained dependencies for calculating the chamber parameters, experimental studies of the shock absorber were carried out. In this case, modern scientific instruments were used. The authors of this work have developed a special pressure sensor to record changes in hydrodynamicpressure inpressure systems during unsteady fluid flow. At thesame time, a reliable agreement between the results of calculations of the shock absorber - the air chamber - and the experimental data was obtained. The completed research experiments prove that the proposed damper is a very effective and economical water shock damper for long pressure pipelinesystems. Keywords: water shock, air chamber, pressure system, positive water shock, water shock with pressure reduction, pumpingunit,check valve. 1.Introduction One of the effective means of protecting pipelines from water shock is an air chamber installed during positive water shock at the end of the pressure pipeline before the valve or water shock with a decrease in pressure at the beginning of the pressure pipeline after the check valve of the pumpingunit and station [1,2,3,4,5]. Calculation of water shock in a pressure pipeline with an air chamber comes down to determining the required volume of air in the chamber to maintain the pressure within acceptable limits[6,7,8,9,10,11]. N.E. Zhukovsky [1] gave an analysis of the processes occurring in the air chamber during direct watershock andformulas fordetermining thevolumeofair inthe chamber. page1132 INTERNATIONAL JOURNAL OF ARTIFICIAL INTELLIGENCE ISSN:2692-5206,ImpactFactor:12,23 AmericanAcademicpublishers,volume05,issue02,2025 Journal: https://www.academicpublishers.org/journals/index.php/ijai I.A. Charny [12] gives a more general solution to the problem using linearized equations of hydromechanics ofa viscous fluid. L.B. Zubov [13] gives an approximate formula for determining the volume of air in the chamber. However, the author's assumption that liquid flows into the chamber occurs during one phase of theimpact raises objections. Alliev theoretically proved that the increase in pressure in the chamber occurs over a time exceeding the impact phase, which was later confirmed by the experiments of A.F. Mostovsky [2]. The listed solutions to the problem of water shock in a pipeline with an air chamber are 2Z applicable for direct water shock under condition t . Therefore, the formulas obtained in a these works are in good agreement with experiment only for small volumes of water shock absorbers -theairchamber [10,11]. 2.Materials andmethods Disregarding the wave nature of the hydrodynamic processes occurring in the pipeline and in the chamber, to solve the problem we used the equation of unsteady motion of an ideal incompressiblefluid ina rigid pipe[10,11,12]. Let's consider a pressure system consisting of a pipeline of length Z with a valve at the end, a reservoir and an air chamber in front of the valve (Fig. 1). The movement of liquid through the pipeline occurs under a pressure of P with an initial speed of ϑ . The volume of air in the 0 0 chamber inthis modeis W . 0 At time t=0, the instantaneous closing of the valve causes unsteady motion, which is described bytheequation [10,11] gZ dJ P = P + , (1) 0 g dt where P is the maximum absolute air pressure in the chamber, P is the absolute air pressure 0 before closing thevalve. To determine thedependenceof Ponϑ,we usethecontinuity equations ϑωdt=-dW (2) andideal gas states [10,11,12,13,14] P W = PW, (3) 0 0 PWk = PWk, (4) 0 0 where dWis thechange in airvolumein thechamber; W is thevolumeofair in thechamber. 0 page1133 INTERNATIONAL JOURNAL OF ARTIFICIAL INTELLIGENCE ISSN:2692-5206,ImpactFactor:12,23 AmericanAcademicpublishers,volume05,issue02,2025 Journal: https://www.academicpublishers.org/journals/index.php/ijai 3.Results andDiscussion The above equations (1), (2), (3) and (4) form closed systems, the solution of which, under the conditionP(ϑ )=P ,isrepresented as: 0 0 Fig.1. Experimental setup diagram: 1 - reservoir; 2 - pressure pipeline; 3 - air chamber; Ω is the transverse area of thechamber. W P P P J2 -J =2g 0 0 ln -1+ 0 , (5) 0 0 W g P P p 0 k-1 1 W P 1 P k P k J2 -J =2g 0 0 -1 -