An improved equation development for longitudinal dispersion coefficient

Abstract

The model developed in this paper is an improved equation for the longitudinal dispersion coefficient, which is an important parameter used to monitor and check the assimilatory capacity of rivers. This research incorporates total suspended solids (Ss) and total dissolved solids (Ds) to other selected functional parameters in order to investigate the contributions of Ss and Ds on the longitudinal dispersion coefficient. The results obtained from research indicates that the presence of Ss and Ds affects longitudinal dispersion coefficient as it reduces the magnitude of Dl values. The measured values of longitudinal dispersion coefficient estimated in this study vary between 71 and 104.4 m2 s-1. The percentage of Dr values estimated to be within 0.0 and 0.3 were 50.0% and within −0.3 and 0.0 were 50% for the developed equation and this indicates a degree of accuracy of 100.0%. While for Seo and Cheong, the percentage of Dr values determined to be within 0.0 and 0.3 were 63.3% and within −0.3 and 0.0 were 30% and gives a degree of accuracy of 93.3% and others are poor. SE, NME and MME results show a high accuracy for the derived equation revealing the adequacy of the derived equation in the estimation of D. HIGHLIGHTS The study accounts for the influence of total suspended solids and total dissolved solids on the dispersion coefficient.; The assimilatory capacity of the river; that is, the ability of the river to absorb the waste.; The re-aeration capacity of the river.; Specific distribution of polluting and toxic materials along a stretch of the river for a pattern of effluent discharges.; Water quality parameters monitoring and evaluation.;

Keywords

• discrepancy ratio
• equation
• longitudinal dispersion coefficient
• total dissolved solids
• total suspended solids