\(V_{\text{CSD}}=\int_{t_{0}}^{t_{f}}Q_{\text{ISD}}\ dt=\int_{t_{0}}^{t_{f}}Q_{B}\left\{\text{erfc}\left[\ \sqrt{\frac{\left(x\right)^{2}\ S_{y}}{4\ T\ t}}\text{\ \ }\right]-\exp\left[\frac{\lambda^{2}\text{\ t}}{4\ S_{y}\text{\ T}}+\frac{\text{λ\ }x}{2\ T}\right]\text{erfc}\left[\sqrt{\frac{\left(x\right)^{2}\ S_{y}}{4\ T\ t}}+\sqrt{\frac{\lambda^{2}\text{\ t}}{4\ S_{y}\text{\ T}}}\text{\ \ }\right]\text{\ \ }\right\}\text{\ dt}\) (1)