Systems development for Mixing Zone field studies

Comparison of near-field mixing zone models for multiport diffusers in the Great Lakes

Canadian Journal of Civil Engineering ◽

10.1139/l94-013 ◽

1994 ◽

Vol 21 (1) ◽

pp. 141-155 ◽

Cited By ~ 5

Author(s):

I.K. Tsanis ◽

C. Valeo ◽

Y. Diao

Keyword(s):

Great Lakes ◽

Environmental Protection Agency ◽

Near Field ◽

Laboratory Data ◽

Field Studies ◽

Mixing Zone ◽

Initial Dilution ◽

Wake Effects ◽

Guidelines And Recommendations ◽

Field Behaviour

This paper presents a review of near-field mixing zone models and compares their performance with common outfall diffuser examples in the Great Lakes. The results of initial dilutions for three types of multiport diffusers, based on the Ontario Ministry of Environment (MOE) guidelines and recommendations, are compared with those calculated by using the U.S. Environmental Protection Agency (EPA) models. These models include five integral-type models (UPLUME, UOUTPLM, UDKHDEN, UMERGE, and ULINE) and a "length scale" type expert system (CORMIX2). Results based on the first four EPA integral models give higher initial dilutions when compared to results based on CORMIX2 and the MOE guidelines, ULINE gives unrealistically low dilutions. Excluding UPLUME, the initial dilutions given by the other EPA models increase with increasing ambient current. Alternating diffusers generally give lower initial dilutions than the staged and unidirectional diffusers, while unidirectional diffusers produce the highest of the three. Results from the computation tests based on the mixing models can aid in more reasonable and economical diffuser designs that still meet the requirement of initial dilution criteria. While all the models selected for this study have limitations, CORMIX2 is preferred for most Great Lakes applications. It can be applied to all four types of multiport diffusers and can handle different types of ambient stratification, bottom and shore attachment, wake effects and dead zones, plume trapping and far-field behaviour. CORMIX2 predictions compare well with laboratory data and very limited field data. Given the complexity of the problem, more field studies should be performed for further validation of the models. Key words: mixing zone, multiport diffusers, initial dilution.

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Dynamics and water structures in the estuary of the Partizanskaya river (Nakhodka Bay, Sea of Japan)

Водные ресурсы ◽

10.31857/s0321-059646124-34 ◽

2019 ◽

Vol 46 (1) ◽

pp. 24-34

Author(s):

P. Yu. Semkin ◽

P. Ya. Tishchenko ◽

V. B. Lobanov ◽

A. F. Sergeev ◽

Yu. A. Barabanshchikov ◽

...

Keyword(s):

Sea Of Japan ◽

Salinity Gradient ◽

Field Studies ◽

Mixing Zone ◽

Run Off ◽

Mouth Bar ◽

Nakhodka Bay ◽

Upper Boundary

Herein, we report field studies of the seasonal and daily dynamics of the mixing zone in the micro-tidal mouth of the Partizanskaya river. The position of the mixing zone was determined according to the volume of river run-off. The upper boundary of the mixing zone was observed at 5 (at a river run-off of 73.67 m3/s) to 12.5 km (at 7.7 m3/s) from the mouth bar. The estuary is characterized by a two-layer circulation of water, which results in a halocline with a salinity gradient of up to 30% per 1 m. Variations of salinity in the rifts caused by tides reaches 27% over 3 h.

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Wastewater diffusion in the estoril coast: theoretical calculations and field studies

Water Science & Technology ◽

10.2166/wst.1998.0420 ◽

1998 ◽

Vol 38 (10) ◽

pp. 337-344 ◽

Cited By ~ 1

Author(s):

J. Matos ◽

A. Monteiro ◽

P. Costa ◽

R. Neves ◽

A. Bettencourt ◽

...

Keyword(s):

Working Conditions ◽

Theoretical Calculations ◽

Monitoring Program ◽

Field Studies ◽

Mixing Zone ◽

Wastewater Discharge ◽

Final Phase ◽

The West ◽

Wastewater Disposal ◽

Tagus River

The Costa do Estoril sewerage system is located on the west side of the Lisbon region, off the mouth of the Tagus river. This system was planned in order to free the pleasant beaches of the region from any wastewater discharge and is prepared to serve, at the final phase, more than one million inhabitants. In the Costa do Estoril a long sea outfall with two diffusers is used for final wastewater disposal. This system has been operating since 1994. In this paper nearfield dilution corresponding to present working conditions are presented. For simulation of nearfield dilution CORMIX 1 and CORMIX 2 (Cornel Mixing Zone Expert System) were applied. The basic data for modelling was selected according to field studies obtained under an ongoing environmental monitoring program.

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