## THERMAL SCIENCE

International Scientific Journal

### EXPLICIT FINITE DIFFERENCE SOLUTION FOR CONTAMINANT TRANSPORT PROBLEMS WITH CONSTANT AND OSCILLATING BOUNDARY CONDITIONS

**ABSTRACT**

For constant and oscillating boundary conditions, the 1-D advection-diffusion equation with constant coefficients, which describes a contaminant flow, is solved by the explicit finite difference method in a semi-infinite medium. It is shown how far the periodicity of the oscillating boundary carries on until diminishing to below appreciable levels a specified distance away, which depends on the oscillation characteristics of the source. Results are tested against an analytical solution reported for a special case. The explicit finite difference method is shown to be effective for solving the advection-diffusion equation with constant coefficients in semi-infinite media with constant and oscillating boundary conditions. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 171011]

**KEYWORDS**

PAPER SUBMITTED: 2019-07-22

PAPER REVISED: 2019-10-04

PAPER ACCEPTED: 2019-10-07

PUBLISHED ONLINE: 2019-11-17

**THERMAL SCIENCE** YEAR

**2020**, VOLUME

**24**, ISSUE

**Issue 3**, PAGES [2225 - 2231]

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