Water jet cutting resistance

Abstract

Abstract The main purpose of the study was establishing the coefficient of hydraulic resistance of two-phase flow using in water jet cutting. In waterjet cutting (JWC) and in abrasive waterjet cutting (AJWC), a two-phase flow consist of water and abrasive solid particles, moves at a high mean velocity (more than 8.0 m/s). Such flows differ from natural and well-studied flows in hydraulic transport. The aim of this work is to investigate experimentally the additional pressure losses during transportation of the abrasive. For the experimental research were used. The supply of fire extinguishing agents is carried out along the sleeve lines, and, as is known, there are pressure losses. In this regard, the problem arises, at what maximum distance from the pumping unit is possible to supply fire extinguishing agents in the form of water and a mixture of water and abrasive particles, and how pressure losses occur in this case, because the flow rates and working pressure of fire extinguishing systems with waterjet cutting are high enough (the working pressure is 30 MPa). The loss of pressure during transportation depends on the flow rate, its viscosity, pipeline characteristics, etc. The results of field studies to determine the basic kinematic characteristics of the two-phase flow are presented. The combination of these parameters is largely characterized by the coefficient of hydraulic friction, which is insufficiently studied for the systems under consideration. As a result of the obtained experimental data, based on the Darcy-Weisbach equation, the coefficient of hydraulic friction was determined, the value of which was 0.019. The coefficient of local resistance was 0.45.