# ISOTHERMAL DISSOLUTION OF A SPHERICAL PARTICLE WITH A MOVING BOUNDARY IN A FLOW FIELD

### Abstract

Numerical solution for isothermal dissolution process of a spherical particle with a moving boundary and the presence of hydrodynamics effects of two different flow fields in a binary solution is described in this paper. The flow fields considered are slow viscous flow or Stokes flow and straining motion or shear flow around the particle. The parabolic differential equations were discretised with finite difference method in space, and the resulting set of ordinary differential equations on time was solved by the method of lines. The analysis includes the radial convective term generated due to the density differences between the solid and liquid phases. The effect due to the natural convection caused by density differences between both phases are evaluated and compared with the effect due to the low Reynolds convective flow field. The numerical solution for the isothermal dissolution of a spherical particle in a binary melt is not only compared with integral method for small times of the process but also the results are verified with mass balance integration. The integral method solutions are found to agree with the numerical results for small time of dissolution.

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*Revista Mexicana De Ingeniería Química*,

*6*(2), 157-168. Retrieved from http://www.rmiq.org/ojs311/index.php/rmiq/article/view/1891

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