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An orifice is used in a pilot line of a system, connected to tank. The pressure in the line, upstream the orifice, is 190 bar, while the tank pressure is atmospheric. If the diameter of the orifice is D = 0.5 mm, evaluate the flow rate lost through it at maximum pressure and the power dissipated through it. Assume oil density ρ = 850 kg/m³ and C_f = 0.62. If the constant specific heat of the oil is 1.8 kJ/kg K, estimate the temperature rise for the fluid across the orifice.

Given:

The pressure drop across the orifice Δp_OR = 190 bar; the orifice diameter D = 0.5 mm; the orifice coefficient C_f = 0.62; the fluid density ρ = 850 kg/m³ and the specific heat coefficient c_p = 1.8 kJ/kg K

Find:

1 the flow rate through the orifice QOR

2 the power dissipated by the orifice POR

3 temperature rise of the fluid through the orifice