HWR Seminar October 5th

“Scale‐Invariant Estimates for Permeabilities of Porous Media”

Dr. Larry Winter

Professor and Department Head

University of Arizona ~ Hydrology & Water Resouces

Three phenomenological power laws for the permeability of porous media are derived from computational experiments on flow through explicit pore spaces. The power laws relate permeability to (i) porosity, (ii) squared mean hydraulic radius of pores, and (iii) their product, which has units of length raised to the fifth power. We call (iii) the "Kozeny predictor" because it is the same independent variable as Kozeny used in his celebrated equation. The pore spaces are represented by three dimensional images of pore networks from seventeen virtual porous media. Images of two physical pore networks and other virtual media are used to independently assess the accuracy of the three models. Their performance is also compared to estimates derived via the Kozeny equation. The power laws provide tighter estimates than the Kozeny equation even after adjusting for the extra parameter they each require. The best fit is with the power law based on the Kozeny predictor. The power is approximately one third, so the law exhibits five‐thirds scaling with length.

WEDNESDAY ~ OCTOBER 5, 2011

Harshbarger Building Room 206 @ 4:00 pm ~

(Refreshments @ 3:45pm outside room 206)

Results from 21st El Dia del Agua

The 21st Annual El Dia del Agua was a huge success! Our heartiest congratulations go to all the winners and to all who participated. For those who were unable to attend, you missed a fantastic day of oral and poster presentations from our graduate and undergraduate students. They were engaging, inspirational, and absolutely outstanding!

Special kudos go to this year's winners:

Melissa Schlegel, winner of the Montgomery Prize, for her oral presentation on "Constraining the timing of microbial methane generation in an organic-rich shale using noble gases, Illinois basin, USA." Melissa's $2000 award was presented by Elizabeth Leon Mora, Errol Montgomery and Associates, Inc. representative and HWR alum.

Rose McAndrew, first place winner of the Hargis Award, for best poster presentation of her work, "Groundwater contaminant transport modeling in the upper Santa Cruz basin." Rose's $1000 award was presented by Dr. David Hargis, principal of Hargis+Associates, Inc. and HWR alum.

Becky Witte, second place winner of the Hargis Award, for best poster presentation of her work, "Evaluating hydraulic responses of soils to cyclic infiltration." Becky's $400 award was also presented by Dr. David Hargis.

Ingo Heidbuechel, winner of the HWR Department Award for best oral presentation of his work, "Determination of the catchment mass transit time distribution." Ingo's $400 award was presented by Dr. Larry Winter, HWR Department Head.

Joel Biederman, winner of the HWR Department Award for best poster presentation of his work, "Changes in snowpack accumulation and ablation associated with mountain pine beetle infestation." Joel's $400 award was also presented by Dr. Larry Winter.

Dylan Cobean, winner of the Donald R. Davis Undergraduate with Distinction Award for best poster presentation of his work, "Comparison and analysis of the 2009 NASS cropland data layer to 2009 field verified crop data throughout southern Arizona." Dylan's $400 award was presented by Dr. Martha Whitaker, Undergraduate Coordinator and HWR alum.

What an outstanding group of student researchers! Congratulations again to all
the winners.

More information on this year's El Dia del Agua here.

- Content courtesy of Terrie Thompson.