Observed mixing lengths in mountain streams

doi:10.1016/0022-1694(77)90081-6

Journal of Hydrology

Volume 35, Issues 1–2, October 1977, Pages 125-136

https://doi.org/10.1016/0022-1694(77)90081-6 Get rights and content

Abstract

Lateral mixing characteristics are investigated from a series of 41 dilution gaugings (slug injections) in five mountain streams (New Zealand). Data are presented which show that mixing lengths for either centre or side injections, can be determined from the simple proportion, $x_{m} ⋍ 25w$ (where x_m is the mixing length and w the mean flow width). Observed mixing lengths are shown to be generally shorter than those predicted by conventional formulae. It is also shown that side injections do not require longer mixing lengths. Both the shorter mixing lengths and the lack of its sensitivity to injection position is probably the result of increased turbulent and mechanical mixing associated with large roughness elements distributed along the flow boundary.

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There are more references available in the full text version of this article.

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Research paperObserved mixing lengths in mountain streams

Abstract

Determinations of mixing lengths in dilution gauging

Int. Assoc. Sci. Hydrol., Publ. No. 78

Electrochemical and fluorometric tracer techniques for streamflow measurements

Br. Geomorphol. Res. Group, Tech. Bull.

Longitudinal dispersion of natural streams

Water Resour. Res.

Longitudinal dispersion in laboratory and natural channels

Calif. Inst. Technol., Rep.

Dispersion of dissolved or suspended materials in flowing streams

U.S. Geol. Surv., Prof. Pap.

Research paper
Observed mixing lengths in mountain streams