changes.mady.by.user Arthur Aslanyan (Nafta College)
Saved on Feb 13, 2019
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p(t,x) = p_i - \frac{q_t}{\sigma \, d} \bigg[ \sqrt{\frac{4 \chi t}{\pi}} \exp \bigg( -\frac{x^2}{4 \chi t} \bigg) - x \, \bigg[ 1- {\rm erf} \bigg(\frac{x}{\sqrt{4 \, \chi \, t}} \bigg) \bigg] \bigg]
p_{wf}(t) = p(t,x=0)= p_i - \frac{q_t}{\sigma \, d} \, \sqrt{\frac{4 \chi t}{\pi}}
