List of top Reservoir Engineering Questions on Reservoir and channel routing

Log-log plot of pressure drop (\( \Delta p \)) versus time (\( t \)) obtained using well test data is matched with one of the Grigarten type curves. Thereafter, a point on the type curve is chosen with \( P_d = 10 \) and \( t_d/C_d = 100 \), where \( P_d, t_d, C_d \) are dimensionless pressure, dimensionless time, and dimensionless wellbore storage, respectively.
The corresponding match point on the log-log plot is \( \Delta p = 250 \) psi and \( t = 10 \) hrs. Oil flow rate is 500 rb/day. Viscosity of oil is 1.5 cP. Thickness of the reservoir is 10 ft and formation volume factor of oil is 1.2 rb/stb.
The permeability of the reservoir is .......... mD (rounded off to one decimal place).
An isotropic and homogeneous oil reservoir has a porosity of 20%, thickness of 20 ft, and total compressibility of \( 15 \times 10^{-6} \) psi\(^{-1}\). Variation of flowing bottomhole pressure (\( p_{{wf}} \)) with time (\( t \)) under pseudo steady state of a drawdown test in the well (under radial flow condition) is given as
\[ p_{{wf}} = 2850 - 5t \] The pressure is in psi and time is in hours. During the well test, the oil flow rate is 1800 rb/day.
The drainage area of the reservoir is .......... acres (rounded off to two decimal places).
A production tubing string of length 1500 m is tightly held by packers to prevent any expansion in either direction. Production of hot gases from the reservoir increases the temperature of the tubing by 20°C. The Young’s modulus of elasticity of the tubing material is 3000 N/m², and the linear coefficient of thermal expansion is \( 5 \times 10^{-6} \) per °C.
Assuming no radial expansion, and neglecting the weight of the gas in the tubing and its viscosity, the increase in the stress of the tubing due to temperature rise is .......... N/m² (rounded off to two decimal places).