Excellence in Geoscience award winners David P. Murphy of Los Alamos High School (on the left) and Joshua B. Shevitz of Pinon Elementary School, Los Alamos on the right. Congratulations!
New Mexico Tech Campus, Socorro NM
April 10, 2014
On April 5th The New Mexico Bureau of Geology and Mineral Resources along with the New Mexico Geological Society and New Mexico Tech’s Earth and Environmental Department presented two Excellence in Geoscience awards at the 2014 New Mexico Science and Engineering Fair on the campus of New Mexico Tech.
Abstracts:
Characterization of Flow Profiles in Laboratory Dust Devils
David P. Murphy, Los Alamos High School, Los Alamos, New Mexico
This research project characterized fluid flow within a laboratory simulation of a minor whirlwind such as a dust devil. Research reported in the literature suggests that tangential velocities can be modeled with a Rankine vortex. Radial and vertical velocities within the fluid flow can be described with models that are consistent with observations of laboratory vortexes and which satisfy the continuity equation.
The validity of the computer model was tested using a number of experimental methods. Laser-scattering experiments were conducted to collect measurements of the vortex core, and particle velocimetry data was used to determine flow velocities outside the core. This data was analyzed to determine the best fit for circulation in the computer model.
The data is consistent with the concentration of updraft and vorticity in the vortex core as expected by the mathematical model. The best fit for updraft velocity used in the computer model was, within uncertainty, equal to the exhaust velocity expected of the apparatus. The calculated value for induced circulation within the apparatus and the fit for circulation in the vortex model were not equal but were proportional by a factor of three.
The computer model accurately describes ideal fluid flow within the vortex, but there are some behaviors observed in vortexes that this computer model does not yet capture. Time-dependent phenomena occurring at the wall of the vortex and within the core have not yet been fully investigated. Future studies will focus on measuring the turbulence and air pressure within these regions of the vortex structure.
Going for the Gold
Joshua B. Shevitz, Piñon Elemenatry School, Los Alamos, New Mexico
The purpose of my experiment was to know where gold could be found in a riverbed with different features. My procedure was to make a model of a riverbed using beach sand. I used black sand (hematite, magnetite, and other minerals) as a tracer to show where the gold would end up. I collected pictural data showing where the black sand went. My conclusions were that the black sand did not end up on the high side of the riverbed. Instead it ended up trapped in the deepest part of the features. I think the black sand did this because it is very dense and couldn’t get past the obstacles. I will use this information when I go gold panning the next time.