Motivation


The 
Temperature Flat Source Solution @model is one of the fundamental solutions of temperature diffusion equations modelling the temperature conduction in linear direction (see Fig. 1).

This temperature profile is very common in subsurface studies, particularly in modelling the temperature above and below the lateral reservoir flow with a temperature


Fig. 1. Sample Temperature Flat Source Solution


Outputs


Temperature distribution


Inputs


Time lapse after the temperature step from   up to 

Spatial coordinate along the transversal direction to constant temperature  plane 

Boundary temperature at 

Thermal diffusivity of the surroundings


Equations


Driving equationInitial conditions Boundary conditions


\frac{\partial T}{\partial t} = a^2 \Delta T = a^2\frac{\partial^2 T}{\partial z^2}



T(t=0, z) = 0



T(t, z=0) = T_f = {\rm const}


T(t, z \rightarrow \infty) = 0



Solution



T(t,z) = T_f \cdot \left[ 1- \mbox{erf} \left( \frac{z}{\sqrt{4at}} \right) \right] = T_f \cdot \left[ 1- \frac{2}{\sqrt{\pi}} \int_0^{z/\sqrt{4at}} e^{-\xi^2} d\xi \right]


where

Error function


See also


Physics / Fluid Dynamics / Linear Fluid Flow 


С. В. Новиков, ТЕПЛОВЫЕ СВОЙСТВА ТЕРРИГЕННЫХ КОЛЛЕКТОРОВ И НАСЫЩАЮЩИХ ФЛЮИДОВ, 2009.pdf


В.М. Фокин, Г.П. Бойков, Ю.В. Видин, ОСНОВЫ ТЕХНИЧЕСКОЙ ТЕПЛОФИЗИКИ, 2004.pdf


Temperature Flat Source Solution @model.pptx


Reference