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Course of ADVANCED MANUFACTURING PROCESSES Proff. Michele Monno – Barbara Previtali – Matteo Strano SURNAME NAME PERSONAL ID Exam - September 12th 2019 Exercise n. 2 – technological problem A company, specialised in the production of waterjet systems, is trying to select and design an intensifier pump for a composites cutting operation. In order to cut the material, the intensifier must operate at Pmax= 410 MPa. In order to avoid delamination of the composite material, the pressure fluctuations must remain within 10% of the maximum pressure, Pmax [MPa]. The tool handling systems is equipped with a single injection head and a primary nozzle with a diameter, dn=0.36 mm, while the Discharge Coefficient is Cd = 0.54. For your selection you have at your disposal two options. The technical specifications of two possible intensifier pumps are summarised in the table 2. Table 2 TECHNICAL SPECIFICATION OF TWO OPTIONS DOUBLE EFFECT INTENSIFIER 3 SINGLE EFFECT INTENSIFIER Maximum power , Wmax [kW] 40 Maximum power , Wmax [kW] 45 Maximum Pressure, Pmax [MPa] 410 Maximum Pressure, Pmax [MPa] 410 Maximum Flow Rate, Qmax [lt/min] 4 Maximum Flow Rate, Qmax [lt/min] 5 Piston diameter (water side), dp [mm] 20 Piston diameter (water side), dp [mm] 23 Piston stroke, s [mm] 125 Piston stroke, s [mm] 125 Attenuator and pipes volume [lt] 2.5 No attenuator - You can assume that the pressure fluctuations are entirely due to the compressibility of the water. At the beginning of each new piston stroke, the outlet valve does not open until water pressure in the cylinder has reached the 410 MPa value. The time required to the piston to bring the pressure up to 410 MPa in the cylinder at the beginning of each new stroke is 0.14 s. While the valve is closed, the pressure at the head is provided by…