Past NZ Rivers Group Events
Although confluence flows are ubiquitous, occurring in geophysical systems, such as river networks, mechanical systems, such as duct or pipe networks, and biological systems, such as arterial or venous networks, understanding of the fluid dynamics of confluences is limited.
This research proposes a generalized framework characterizing the fluid dynamics of open-channel confluences with a concordant bed, including an-in depth investigation of the physics of shallow mixing layers developing over a no-slip surface. Using eddy-resolving numerical simulations in idealized geometries, we systematically examine the main parameters (confluence angle, velocity ratio, density ratio, curvature of the downstream channel) that control confluence fluid dynamics and the influence of this dynamics on mixing between the two incoming streams. In particular, we investigate the role played by the quasi-2D large-scale eddies generated within the mixing interface and by the streamwise-oriented vortical (SOV) cells forming in the vicinity of the mixing interface in mixing.
We show that the main reason why SOV cells have a large capacity to enhance mixing and to entrain sediment from the bed in the case of a loose-bed boundary is because their cores are subject to large-scale bimodal oscillations toward and away of the mixing interface.
Finally we discuss some examples where shallow mixing interfaces form at river confluences with natural bathymetry and in particular the role played by density differences between the incoming streams on hydrodynamics and mixing of concordant bed confluences.
No RSVP required!
The ability of animals to sense and navigate complex environments is unrivaled by even the most sophisticated robots known to humans. Nowhere is this more challenging to understand than in the three-dimensional environment of water, where animals are unconstrained by gravity, often in turbulence flows, and appendages and bodies are at the mercy of complex fluid-structure interactions.
Fishes, which comprise over half of all living vertebrates, have an exquisite control mechanism for negotiating turbulence. I will describe advances my lab has made in understanding how fish swim in unsteady flows, and how by study nature’s designs we can reveal insights into some of the biggest challenges in engineering and robotics.
No RSVP required!
Why attend the “lessons learnt from the large flood events in the Bay of Plenty Region” workshop?
The River Manager’s forum is a group of river managers from all regional and unitary councils across New Zealand, who come together to share knowledge, experiences and lessons learnt in the management of New Zealand Rivers from a council perspective. The Rivers Group is a forum for all those with an interest in rivers, flood risk management and the operational and environmental issues of catchments and river systems.
Understanding River Management in the Bay of Plenty
Understanding the events leading up to large flood events, things that unfolded during those flood events, and the response from the Regional Council and Civil Defence, help us collectively to understand and plan for future flood events.
- Learn about the Rangitāiki River flood scheme and the Rangitāiki floodway, and some of the challenges the council faces moving forward.
- Hear about BOPRC’s flood forecasting model for the Rangitāiki River, and how it performed in light of the 2017 flood event.
- Learn more about the three major flood events that have occurred in the Bay of Plenty in the last few years, and the independent reviews and recommendations from two of these.
- This event is a unique opportunity to network with river professionals and leaders in river management.
- There is an opportunity for robust discussion with the BOPRC river management team during the panel discussion.
- Inspire each other with our stories of success, challenges and celebration.
- Participate in an interactive field trip through the Rangitāiki River with those involved with managing the river.
|Member Early Registration||$350.00|
|Member Late Registration||$450.00|
|Non-member Early Registrations||$430.00|
|Non-Member Late Registration||$500.00|
|Student Full Registrations early & late||$280.00|
|Day One only member||$290.00|
|Day one only Non-Member||$320.00|
|Field Trip Only||$85.00|
Engineering New Zealand/Water NZ Rivers Group are excited to invite you to the 2018 Conference to be held in Palmerston North on 21 -22 November.
The conference theme is “Emerging Understanding on Key Issues Facing New Zealand’s Rivers”. On day one, delegates will hear from a number of members from the industry and leading researchers on a range of subjects related to the challenges and successes of New Zealand Rivers. Day two includes a field trip to the Manawatu River and Gorge.
We look forward to seeing you in Palmerston North this coming November.
Engineering NZ and Water NZ Rivers Group have confirmed their support for the upcoming 2018 Waterways Postgraduate Conference. The Rivers Group is providing some financial support to help run the day and will also be giving out two student awards for best oral and poster river management presentations. This event showcases the latest research being undertaken by postgraduate students of University of Canterbury and Lincoln University in the field of freshwater management.
Climate change is expected to increase the risk of coastal hazards around New Zealand as sea level rises. Join us for an update on the latest sea level rise science and a new approach to support coastal communities prepare for long term change.
Dr Rob Bell (NIWA), Dr Judy Lawrence (Victoria University) and Emma Lemire (Ministry for the Environment) will present on the key information from the Ministry for the Environment’s updated Coastal Hazards and Climate Change guidance document:
- National guidance on sea level rise projections and the latest science
- The relationship between climate change and coastal hazards
- Using sea level rise scenarios in adaptive planning
- Engagement expectations between councils and communities
- Community planning under conditions of uncertainty (the dynamic adaptive pathways planning approach)
Following the presentations, there will be time for questions and discussion.
Sponsored by the New Zealand Coastal Society
“The ups and downs of tectonics, sea-level and sediment supply in the recent geological history of Wellington Harbour (Te Whanganui a Tara)”
By Scott D. Nodder – Principal Scientist, Marine Geology, NIWA
“So Why do we need a Supercomputer to forecast the Weather?”
By Michael Uddstrom, Principal Scientist, Environmental Forecasting, NIWA
Tour of NIWA’s Greta Point Facilities
RSVP | Car-pool info | Event Information:
Hamish Smith firstname.lastname@example.org
Ana Serrano email@example.com
Waterways Centre Postgraduate Student Conference that showcases student’s freshwater related research. Student prizes will be presented from the Rivers Group.