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Popular QuestionsExpected Solution for Species Equation
https://confluence.gomafem.com/questions/34308187/expected-solution-for-species-equation
<p>If I solve the 1D, steady state, species equation (2D mesh with no-flux conditions on the top/bottom of dimensions 1x1) with no flow turned on, then it should be a pure diffusion problem.</p><p>If I impose boundary conditions Flux_left = C and Flux_right = C - 1, then I expect a linear profile which varies between C=1/3 on the left boundary and C=2/3 on the right boundary.</p><p>However, this is not the solution that I get. Instead, I get C_left = 0.4762 and C_right = 0.5238.</p><p>If I do this setup with the heat equation, I get exactly the result I expect.</p><p><br/></p><p>I am sure I am missing something basic about the species equation, but I would appreciate help nonetheless.</p>speciesSat, 06 Jun 2020 00:12:16 GMTtag:https://confluence.gomafem.com,2014:question-34308187Scott Dossa2020-06-06T00:12:16ZInternal capillary condition
https://confluence.gomafem.com/questions/34308163/internal-capillary-condition
<p>There is a capillary BC set for an externally facing boundary.</p><p>However, is there a capillary BC which can be used between two liquids or a liquid-gas interface or does one need to be written?</p>capillaryinternalboundaryWed, 20 May 2020 01:43:29 GMTtag:https://confluence.gomafem.com,2014:question-34308163Scott Dossa2020-05-20T01:43:29ZSpecies flux notation in manual
https://confluence.gomafem.com/questions/34308129/species-flux-notation-in-manual
<p>Is the species flux "J" used in the goma manual total flux or diffusive flux?</p><p>Ex 1:</p><p>For the boundary condition YFLUX, the equation is written in the manual as:</p><p>nJ + n (v-vm) = k (c-c_inf)</p><p>Are we assuming here that J is the <u>total flux</u>? That is, another way to write this equation is:</p><p>nD nabla c = k(c-c0) .</p><p><br/></p><p>Ex 2:</p><p>For the boundary condition YFLUX_EQUIL, the equation is written in the manual as:</p><p>J = k(w-w_inf)</p><p>Are we assuming here that J is also <u>total flux</u>? That is, the condition can be written as</p><p>nD nabla c - n(v-vm) = k(w-w_inf) .</p>speciesmanualfluxnotationFri, 15 May 2020 18:57:10 GMTtag:https://confluence.gomafem.com,2014:question-34308129Scott Dossa2020-05-15T18:57:10Z