Acquisition of a Volumetric Velocimetry System

Fluid flows in nature vary intrinsically over space and time. Simultaneously mapping the flow field within a three-dimensional (3D) volume will allow the full characterization of not only the flow field, but also the pressure field and any shear and normal forces within the fluid and at boundaries. This will have a transformative impact on our ability to characterize solute mixing, particle and solute transport, and aquatic organisms, ranging from microorganisms within porous media to fish moving in a river.

This project funds the acquisition of a Volumetric Velocimetry System (VVS) to support experimental research that will map flow fields in physical models of geoscience phenomena. The VVS will provide researchers the capability to acquire volumetric realizations of flow structures using this minimally invasive tool. Example applications of the system include model studies of breakout during surface lava flow which will improve prediction of when lava will arrive at specified location.

In a second application, the VVS will probe critical questions about and solute and sediment grain transport in streambeds. Results from these studies will, for example, improve predictions of channel stability and be applied to the design of river restoration projects. Lastly, volumetric descriptions of the experimental flow fields from this system will be powerful tools for the validation of complex computational models, which are becoming a common investigative tool even though in many circumstances models are not benchmarked with proper data.

A web presence highlighting VVS projects will provide visualizations and links to available data. A partnership with a local middle-school teacher will facilitate visits of local students to the Center for Ecohydraulics Research at University of Idaho.

The acquisition of a Volumetric Velocimetry System (VVS) will enable researchers to overcome the crucial shared challenge faced by scientists and engineers who seek understanding of the fundamental nature of several types of fluid flows: the inability to acquire all three temporally and spatially resolved components of velocity data and their spatial and temporal derivatives, whose information will allow direct solution the Navier-Stokes equations retrieving information on the pressure and force distribution. Moreover, volumetric descriptions of the experimental flow fields from this system will be powerful tools for the validation of complex computational models, which are becoming a common investigative tool even though in many circumstances models are not benchmarked with proper data.

Pursuing these research avenues will yield insights into geoscience phenomena, including entrainment in deep-sea hydrothermal systems and breakout during surface lava flows. In addition, coupling the VVS with the refractive index matching will probe critical questions about microbial colonization of pore interstices, turbulence dissipation at and within streambeds and its impact on organisms, and solute and sediment grain transport in streambeds.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.