A new model based on dimensional analysis for predicting longitudinal dispersion in streams
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International Journal of Recent Engineering Science (IJRES) |  |
| © 2017 by IJRES Journal | ||
| Volume-4 Issue-6 |
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| Year of Publication : 2017 | ||
| Authors : Ikebude C.F, J.C. Agunwamba |
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| DOI : 10.14445/23497157/IJRES-V4I6P101 |
How to Cite?
Ikebude C.F, J.C. Agunwamba, "A new model based on dimensional analysis for predicting longitudinal dispersion in streams," International Journal of Recent Engineering Science, vol. 4, no. 6, pp. 1-6, 2017. Crossref, https://doi.org/10.14445/23497157/IJRES-V4I6P101
Abstract
This paper presents a new model for predicting dispersion coefficient in a stream. The developed model is based on dimensional analysis. Application of dimensional analysis to water quality modelling is presented, pointing out possibilities of applying this methodology in water quality research. Buckingham pie theory method was used in this study which lead to the formation of four (4) dimensionless groups. Appropriate regression method was used to obtain the constants. Stream and air temperature was incorporated into the model alongside other conventional parameters proposed in literature that influences dispersion such as velocity, shear velocity, width and depth. The model was developed calibrated and evaluated using data from the new-calabar river, southern Nigeria. The model was compared with other existing conventional model for predicting dispersion coefficient and it performed satisfactorily. The developed model gave coefficient of determination value of 0.9716, root mean square error of 0.5721 and discrepancy ratio of 4% (0.04). These values are pointers to the fact that the model is reliable for prediction. Inclusion of temperature into the model improved the predictive capacity of the model.
Keywords
Dimensional analysis, water quality, temperature, prediction, regression.
Reference
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