Secondary circulation is a mechanism that increases vertical exchange between the horizontal layers in open channels. Vertical shear curved flows induces secondary plane normal to primary flow direction. Models for have been developed include nonlinear advection terms momentum equations. A consequence of this deforms profile flow. This turn reduces thus reducing driving force circulation. Observations from bend moderate curvature Clutha river show flattening and deformation due by The...

Aotearoa New Zealand is a land and cultures surrounded by one of the planet's larger marine exclusive economic zones per capita. Understanding, living within utilising this domain requires well-developed knowledge physical oceanography – fate, provenance transfer ocean-water, material energy. In context, understanding environment through science also that Māori have stake in pathway to connecting with their mātauranga. The pūtahitanga (intersection) mātauranga western perspectives brings...

The upwelling of nutrient-rich bottom waters supports life at the oceans' surface. Secondary circulation can produce localized headlands. develops in curved flow around headlands resulting a loose helical pattern within flow. magnitude secondary be up to 20% depth average current. Moving vessel ADCP measurements were taken Cape Saunders, Otago Peninsula, New Zealand. radial basis function interpolation techniques for smoothing noisy data allows weak horizontal extracted from stronger along...

Abstract Wind‐driven mixing and Ekman pumping driven by slow‐moving tropical cyclones (TCs) can bring nutrients to the euphotic zone, promoting phytoplankton blooms (TC‐PBs) observable satellite remote sensing. We examine an exceptional ( z ‐score = 18–48) TC‐PB induced category‐1 Cyclone Oma near South Pacific island of Vanuatu in February 2019, most extreme event observed record surface Chlorophyll‐ a (Chl‐ ). Examining all 156 TC since 1997, we identify “hover” parameter derivable from...

Abstract High‐resolution observations from the curved tidal channel of Otago Harbour shows secondary flows up to 20% primary flow and vertical velocity inferred 1% flow. This is on a much finer scale than previous works. The spatial pattern this upward inside downward outside bend, consistent with laboratory flume measurements. Linear regression, r p = 0.95, cross‐channel distribution observed can be resolved horizontal ADCP measurements well enough derived using model Kalkwijk Booij (1986)....

Abstract Drilling and completing Enhanced Geothermal Systems (EGS) / geothermal wells poses unique well construction problems challenges. These operations have proven to be especially challenging for the drilled in Cooper Basin, South Australia. High temperatures encountered, combination with high pressures are a key consideration design of well, both drilling stimulation operations. A failure 2009 led an in-depth investigation into cause failure. Results revealed most probable was caustic...

A simple diagnostic narrow channel shallow water model for the cross-channel distribution of depth average velocity is developed. It diagnostic, because slope stream-wise free surface specified and it models without any knowledge field. non-dimensional parameter that encapsulates dimensions relative importance bottom friction to horizontal eddy viscosity defined. Numerical solutions are obtained using values this different topographies. in turn used find secondary flow vertical velocity....

Bottom friction causes a vertical shear in the water column resulting secondary circulation causing helical flow pattern around curved open channels. Secondary has cross-stream and components. Current models for include 'non-linear' advection terms momentum equations. Advection due to deforms profile of primary which would normally be logarithmic shape. A consequence this is that reduced turn reduces driving force flow. Moving vessel Acoustic Doppler Profiler (ADCP) measurements from tidal...