7/24/2019 SafetyValve_Outlet Static Pressure Calculation

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Calculation of Outlet Static Pressure at Safety Valve

Set Pressure, Pset

  50 kg/sqcmg   49.35 bargOverpressure, Pover 3%   1.5 kg/sqcmg   1.48 bar

Backpressure, Pback 10%   5 kg/sqcmg   4.93 bar

Inlet Loss, Pinlet   0 kg/sqcmg   0.00 bar

Atmospheric Pressure, Patm   1.0332 kg/sqcma   1.013 bara

Safety Valve outlet diameter 154.05 mm   15.41 cm

Area at outlet, Ao   186.39 sqcm

Orifice Area 41.16 sqcmRelieving Pressure, P1=Pset+Pover-Ploss+Patm   51.84 bara

Kd Discharge coefficient 0.98

Kn Napier correction factor 1.00

Ksh Superheat correction factor 1.00

Ksc Superheat correction factor 1.00

Kc Rupture disk CCF 1.00

Inlet stagnation enthalpy, ho 2792.90 kJ/kg

Outlet static pressure, Po   =(0.01812*A*P_1*kd*kn*ksh*ksc*kc*((h_0-1914.3)^0.5/A_o))-Patm

Outlet static pressure, Po 4.98 barg