Gray Functions
Gray (1974) correlation for gas and gas-condensate wells.
3 functions
PO.VFP.Gray.dPdL(Ql, Qg, P, Rho_l, Ul, Bl, Rho_g, Ug, Bg, IFT_gl, Rs, pipe_ID, pipe_roughness, pipe_angle)
Calculates pressure gradient for multiphase pipe flow using Gray (1974) correlation, [psi/ft]. Commonly used for gas wells that are also producing liquid.
PO.VFP.Gray.Pout(Ql, Qg, P_in, T_degF, Rho_l, Ul, SG_gas, IFT_gl, pipe_ID, pipe_length, pipe_roughness, pipe_angle)
Calculates outlet pipe pressure using Gray (1974), [psi]. For gas wells producing liquid. Gas properties (ρg, μg, Bg) use DAK (Z-factor) and LGE (viscosity).
PO.VFP.Gray.Pin(Ql, Qg, P_out, T_degF, Rho_l, Ul, SG_gas, IFT_gl, pipe_ID, pipe_length, pipe_roughness, pipe_angle)
Calculates inlet pipe pressure using Gray (1974), [psi]. For gas wells producing liquid. Gas properties (ρg, μg, Bg) use DAK (Z-factor) and LGE (viscosity).