Open Access Open Access  Restricted Access Subscription or Fee Access

River Pollution Modelling in Determining the Level of Dissolved Oxygen Concentration Using Laplace Transforms

Nurra Mahadi, Zainal Abdul Aziz, Mahad Ayem

Abstract


In the present study, the advection-diffusion equation is solved to determine the level of dissolved oxygen (DO) concentration. For problems related to river pollution, DO is the most important element to predict the water quality level other than Biochemical Oxygen Demand (BOD) or pollutant concentration. The problems are considered and solved either with dispersion oxygen or without dispersion for unsteady state condition which are developed to solve the problems in order to have a realistic model. Then, two cases are considered for each problem; (i) presence of half saturated oxygen for DO and (ii) absence half saturated oxygen for DO. For simplified cases, the linear model is analytically solved by using Laplace and inverse Laplace transform method. But, for the nonlinear model we solved numerically by finite difference method. Then, the results are presented graphically with the dependency on various respective parameters. Finally, the comparison between both steady and unsteady states is made. Such a mathematical model with analytical solutions can help the management of water quality and generically able to solve river pollution problems with slight modifications for other rivers of interest.

Keywords


advection-diffusion equation, Laplace transforms, dissolved oxygen.

Full Text:

PDF


Disclaimer/Regarding indexing issue:

We have provided the online access of all issues and papers to the indexing agencies (as given on journal web site). It’s depend on indexing agencies when, how and what manner they can index or not. Hence, we like to inform that on the basis of earlier indexing, we can’t predict the today or future indexing policy of third party (i.e. indexing agencies) as they have right to discontinue any journal at any time without prior information to the journal. So, please neither sends any question nor expects any answer from us on the behalf of third party i.e. indexing agencies.Hence, we will not issue any certificate or letter for indexing issue. Our role is just to provide the online access to them. So we do properly this and one can visit indexing agencies website to get the authentic information. Also: DOI is paid service which provided by a third party. We never mentioned that we go for this for our any journal. However, journal have no objection if author go directly for this paid DOI service.