Single-phase gas flow (subsonic)
Input(s)
\(P_{d}\): Downstream Pressure \((\mathrm{psi})\)
\(P_{u}\): Upstream Pressure at Choke \((\mathrm{psi})\) k: Specific Heat Ratio (dimensionless) A: Cross Sectional Area of Choke (in. \({ }^{2}\) )
\(\gamma_{g}\) : Gas Specific Gravity related to Air (dimensionless)
\(T_{u}\): Upstream Temperature (R)
\(C_{d}\) : Choke Discharge Coefficient (dimensionless)
Output(s)
\(q_{s c}\): Gas Flow Rate \((\mathrm{Mscf} / \mathrm{D})\)
Formula(s)
\[
q_{s c}=1248 * C_{d} * A * P_{u} *\left(\left(\left(\frac{k}{(k-1) * \gamma_{g} * T_{u}}\right) *\left(\left(\frac{P_{d}}{P_{u}}\right)^{\frac{2}{k}}-\left(\frac{P_{d}}{P_{u}}\right)^{\frac{k+1}{k}}\right)\right)^{0.5}\right)
\]
Reference(s)
Boyun, G., William, C., & Ali Ghalambor, G. (2007). Petroleum Production Engineering: A Computer-Assisted Approach, Page: 5/61.