Answer Happy

A vertical well is producing oil and gas from a circular oil reservoir. No water exists in oil reservoir. The reservoir boundary is a no-flow boundary, or the reservoir is a closed- system with no connection with aquifer. Well and reservoir data are given below. = Tubing relative roughness, E= 0.0005 Tubing inner diameter, Drube = 2 in. Constant temperature in the whole system, T= 150 F Skin factor, S=5 Oil specific gravity, yo = 0.8 Oil formation volume factor for all oil reservoir pressure, B. = 1.2 rb/STB Production gas-oil ratio, GOR= 800 SCF/STB Gas-oil interfacial tension, o= 40 dynes/cm Gas specific gravity, V: = 0.7 Constant gas viscosity in the whole system, ug = 0.02 cp Constant gas z-factor in the whole system, z = 1 Constant oil viscosity in the whole system, Ho = 2 cp Wellhead pressure, Pwh=200 psi Initial reservoir pressure, p = 6000 psi Bubble point pressure, p5 = 6000 psi Pay zone thickness, h=60 ft Total compressibility, ct=0.000013 psi-1 Drainage area, A = 640 acres (re= 2980 ft) Original reservoir porosity, 6 = 0.2 Oil permeability, ko = 40 md Reservoir depth (= well depth), Depth = 9500 ft Wellbore radius, Yw= 0.328 ft Reservoir temperature, T= 150 °F The inflow performance relationship curve of the saturated oil reservoir can be described by Vogel model = Pwf 90 = 90 m Pwf 1-0.2 р -0.81 max р
1. Calculate the oil and gas production rates (oil rate in STB/day; gas rate in Mscf/day) of the well at times of 6, 12, 18, 24, 30, 36, 48, 60, 72, 84, 96, 108, and 120 months. 2. What is the bottomhole pressure when oil production rate is 20.0 STB/day? What is the producing time when oil production rate is 20.0 STB/day?