# International Association for Hydro-Environment Engineering and Research

IAHR, founded in 1935, is a worldwide independent member-based organisation of engineers and water specialists working in fields related to the hydro-environmental sciences and their practical application. Activities range from river and maritime hydraulics to water resources development and eco-hydraulics, through to ice engineering, hydroinformatics, and hydraulic machinery.
 You are here : eLibrary : IAHR World Congress Proceedings : 36th Congress - The Hague (2015) ALL CONTENT : Hydro-environment : Analysis of processes affecting the thermal pollution spreading in rivers
 Analysis of processes affecting the thermal pollution spreading in rivers Author : MONIKA B. KALINOWSKA(1), MAGDALENA M. MROKOWSKA (1) & PAWEŁ M. ROWIŃSKI(1) While solving practical problems concerning thermal pollution spreading in rivers, many questions about the importance of the processes affecting the mixing arise. Heat transport in rivers in general case should be described by threedimensional (3D) differential equation (see e.g. Szymkiewicz, 2010). But solution of such equation requires huge amount of data that are usually difficult to obtain. The computational costs of the solution are also very high, so different simplifications are considered in practice. Since the mixing along the depth is relatively fast, the most obvious simplifications pertain to the reduction of the problem to two (2D) or even one dimension (1D). In practical applications the 2D models have been shown to give reasonable results. 1D models may be also very useful, but very often they are used without proper justification for large rivers with complicated geometries. 1D approach may be used in the far-field zone after complete vertical and horizontal mixing (while the mixing along the depth is relatively fast, the mixing along the width can take a very long time). Nevertheless sometimes such approach is unavoidable even in mid-field zone where there is no enough data to use the 2D models, but then results are biased by large errors. Additional simplifications are related to the particular terms of heat equation that have to be estimated i.e.: the sources function describing additional heating or cooling processes, the dispersion tensor components in 2D equation (see e.g. Kalinowska and Rowiński, 2008; Rowiński and Kalinowska, 2006) or longitudinal dispersion coefficient in 1D equation (see e.g. Wallis and Manson, 2004). File Size : 138,201 bytes File Type : Adobe Acrobat Document Chapter : IAHR World Congress Proceedings Category : 36th Congress - The Hague (2015) ALL CONTENT Article : Hydro-environment Date Published : 30/09/2015 Download Now