CHAPTER 7
SINGLE-PHASE FLUID FLOW IN RESERVOIRS
PROBLEM 7.1 Two wells are located 2500 ft apart. The static well pressure at the top of perforations (9332ft subsea) in well A is 4365 psia and at the top of perforations (9672 ft subsea) in well B is 4372 psia. The reservoir fluid gradient is 0.25 psi/ft, reservoir permeability is 245 md, and reservoir fluid viscosity is 0.63 cp. a) Correct the two static pressures to a datum level of 9100 ft subsea b) In what direction is the fluid flowing between the wells? c) What is the average effective pressure gradient between the wells? d) What is the fluid velocity? e) Is this the total velocity or only the component of the velocity in the direction between the two wells? f) Show that the same fluid velocity is obtained using Eq. (7.1). ANSWER: a)
φ a = p a − 0.25ha ha = 9332 − 9100 = 232 ft
φ a = 4365 − (0.25 × 232) = 4307 psia φb = pb − 0.25hb hb = 9672 − 9100 = 572 ft
φb = 4372 − (0.25 × 572) = 4229 psia 104