changes.mady.by.user Arthur Aslanyan (Nafta College)
Saved on Feb 11, 2022
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s_w = \left[ \frac{\sqrt{\frac{1}{R_t}}}{ \frac{V_{sh}^{(1-0.5 \, V_{sh})}}{\sqrt{R_{sh}}} + \sqrt{ \frac{\phi_e^m}{A \, R_w}}} \right]^{\, (2/n)}
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\frac{1}{R_t} = \frac{\phi_e^m \, s_w^n }{A R_w} \quad \Rightarrow \quad s_w = \Big ( \frac{A}{\phi_e^m} \; \frac{R_w}{R_t} \Big) ^{1/n}
where constant
\frac{1}{A} = 1 + \Big( \frac{V_{sh}^{2-V_{sh}}}{\phi_e} \, \frac{R_w}{R_{sh}} \Big)^{1/2}
where
1.5 ÷ 2.5, default value is 2