Critical rate for horizontal Wells in edge-water drive reservoirs

Input(s)

e1: Constant for $\mathrm{C} 1$ Equals +0.023 or -0.023 (dimensionless)

$e 2$: Constant for $\mathrm{C} 2$ equals +0.0013 or -0.0013 (dimensionless)

e3: Constant for $\mathrm{C} 3$ equals +0.022 or -0.022 (dimensionless)

e4: Constant for $\mathrm{C} 4$ equals +0.0013 or -0.0013 (dimensionless)

$\Delta_{\rho}$: Density Difference between water and oil or, oil and gas $(\mathrm{gm} / \mathrm{cc})$ h: Pay Zone Thickness (ft)

L: Length of Well (ft)

$x_{e}$: Distance between Horizontal Well and Constant Pressure Boundary (ft)

$\mu_{o}$: Oil Viscosity $(\mathrm{cP})$

$k_{h}$: Vertical Permeability $(\mathrm{mD})$

$k_{v}$: Horizontal Permeability $(\mathrm{mD})$

Output(s)

$c_{1}$: Dimensionless Constant for calculation (dimensionless)

$c_{2}$: Dimensionless Constant for calculation (dimensionless)

$c_{3}$: Dimensionless Constant for calculation (dimensionless)

$c_{4}$: Dimensionless Constant for calculation (dimensionless)

$q_{c}$: Dimensionless Critical Rate per Unit length (STB/day/ft)

$q_{o}$: Critical Rate (STB/day)

$z_{c}$: Critical Height Representing the Difference between the Apex of the Gas/Water Crest from the Well Elevation $(\mathrm{ft})$

Formula(s)

Reference(s)

Joshi, S.D. 1991, Horizontal Well Technology. Tulsa, Oklahoma: PennWell Publishing Company. Chapter: 7, Page: 309,310 .