LAB Announcements

Spotlight

Bhagirath Addepalli

Bhagirath Addepalli

Hometown: Hyderabad, India

Program: PhD (Graduated May 2012)

Current Position: Microsoft Program Manager

Research Interests: Fundamental and applied research in fluid dynamics, inverse and optimization techniques, and statistical modeling and analysis of data. Specifically, interests include: laboratory experiments, computational fluid dynamics, Lagrangian random-walk modeling, development of novel case-specific objective functionals (metrics) for inverse problems, development of efficient and robust optimization and inversion techniques spanning deterministic, stochastic (frequentist), and Bayesian methods, multiple criteria decision making (MCDM - Pareto optimality), linear and nonlinear regression techniques for stochastic modeling, statistical modeling of time series data, model selection in inverse problems.

Publications:
A) Journal Publications / Pre-prints:
a) Addepalli, B., K. Sikorski, E.R. Pardyjak and M.S. Zhdanov. Source characterization of atmospheric releases using stochastic search and regularized gradient optimization. Inverse Problems in Science and Engineering, 2011. 19(8): p. 1097-1124.
b) Addepalli, B. and E.R. Pardyjak. A pseudo-metric to handle zero measurements and predictions in atmospheric inverse-source problems. Under review. Submitted to Inverse Problems in Science and Engineering.
c) Addepalli, B. and E.R. Pardyjak. Investigation of flow structure in step-up street canyons. Ready to be submitted to Boundary Layer Meteorology. Pre-print available upon request.
d) Addepalli, B. and E.R. Pardyjak. Study of flow fields in asymmetric step-down street canyons. Ready to be submitted to Boundary Layer Meteorology. Pre-print available upon request.
e) Addepalli, B., E.R. Pardyjak, P. Willemsen and D.E. Johnson. Urban form optimization for air quality applications using simulated annealing and genetic algorithms. Ready to be submitted to Atmospheric Environment. Pre-print available upon request.
f) Addepalli, B. Markov Chain Monte Carlo annealing for atmospheric inverse-source problems. To be submitted to Inverse Problems in Science and Engineering. Pre-print available upon request.

B) Peer-reviewed Conference Publications:
a) Addepalli, B., K. Sikorski, E.R. Pardyjak and M.S. Zhdanov. Quasi-Monte Carlo, Monte Carlo, and regularized gradient optimization methods for source characterization of atmospheric releases. in Dagstuhl Seminar Proceedings 09391, Algorithms and Complexity for Continuous Problems. 2009. Dagstuhl, Germany: Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik, Germany.
b) Addepalli, B. and E.R. Pardyjak. Study of flow fields in asymmetric step-down street canyons. in The International Workshop on Physical Modelling of Flow and Dispersion Phenomena (PHYSMOD). 2007. University of Orleans, France.

C) Conference Publications:
a) Pardyjak, E.R., Addepalli, B., et al., Impact of green infrastructure on urban microclimate and air quality, in the 8th International Conference on Urban Climate - ICUC 8. 2012: Dublin, Ireland.
b) Addepalli, B. and C. Sikorski, A note on objective functions for atmospheric inverse-source problems, in second National Conference in Advancing Tools and Solutions for Nuclear Material Detection. 2011: Salt Lake City, UT.
c) Addepalli, B. and C. Sikorski, Efficient adaption of simulated annealing and genetic algorithms to atmospheric inverse-source problems, in AIChE Annual Meeting. 2010: Salt Lake City, UT.
d) Addepalli, B. and C. Sikorski, Tools to characterize the source of hazardous releases, in 1st National Conference on Advancing Tools and Solutions for Nuclear Material Detection. 2010: Salt Lake City, UT.
e) Addepalli, B., M.J. Brown, E.R. Pardyjak and I. Senocak. Evaluation of the QUIC-URB wind model using wind-tunnel data for step-up street canyons, in Seventh Symposium on the Urban Environment. 2007: San Diego, CA.
f) Addepalli, B. and E.R. Pardyjak. 2D PIV Measurements of street canyon flow for buildings with varying angles and separation distances. in American Meteorological Society Sixth Symposium on the Urban Environment. 2006: Atlanta, GA.

D) Conference Presentations:
a) Addepalli, B., E.R. Pardyjak, P. Willemsen and D.E. Johnson. GPU-MCDM: A new module of the Quick Urban and Industrial Complex (QUIC) dispersion modeling system for urban form optimization. in the 8th International Conference on Urban Climate - ICUC 8. 2012: Dublin, Ireland.
b) Addepalli, B., E.R. Pardyjak, P. Willemsen and D.E. Johnson. Development of a multiple criteria decision making (MCDM) tool for urban form optimization. in 92nd AMS Annual Meeting. 2012: New Orleans, LA.
c) Addepalli, B., E.R. Pardyjak, P. Willemsen and D.E. Johnson. Urban form optimization for air quality applications using simulated annealing and genetic algorithms. in Ninth Symposium on the Urban Environment. 2010: Keystone, CO.
d) Addepalli, B., M.J. Brown, E.R. Pardyjak and I. Senocak. Investigation of the flow structure around step-up, step-down, deep canyon, and isolated tall building configurations using wind-tunnel PIV measurements, in Seventh Symposium on the Urban Environment. 2007: San Diego, CA.
e) Addepalli, B., E.R. Pardyjak and M.J. Brown. The effect of geometry on the wake structure of a surface mounted obstacle. in 60th Annual Meeting of the APS Divison of Fluid Dynamics. 2007: Salt Lake City, UT.
f) Addepalli, B. and E.R. Pardyjak. Experimental investigation of the effect of Reynolds number and HΔ value on flow fields in street canyons with cubical Buildings. in American Physical Society, 59th Annual Meeting of the APS Division of Fluid Dynamics. 2006: Tampa Bay, FL.
g) Addepalli, B. and E.R. Pardyjak. 2D PIV measurements of flow between a pair of model buildings with varying geometries. in American Physical Society, 58th Annual Meeting of the Division of Fluid Dynamics. 2005: Chicago, IL.

E) Technical Reports:
a) Addepalli, B., C. Sikorski and E.R. Pardyjak. Source Characterization of atmospheric releases using quasi-random sampling and gradient optimization. Report submitted to the School of Computing, University of Utah. Report number: UUCS 09-001.
b) Nelson, M., B. Addepalli, D. Boswell and M.J. Brown. QUIC Start Guide (v 4.5). Los Alamos National Labratory. LA-UR-07-2799.

Contact: addbugs@gmail.com

Past Research Projects

Atmspheric Field Measurement Projects

 An insturmented street canyon at during MUST

Mountain Terrain Field Campaigns

The MATERHORN Project:

 Sage Brush extended flux tower This ONR (Office of Naval Research) funded MURI (Multidisciplinary University Research Initiative) project was led by the University of Notre Dame built on our research group’s work related to flow in complex terrain and during transition periods. It was designed to better understand flow and turbulence processes in mountainous terrain for improved mesoscale modeling. The project improved understanding of turbulent transport processes in the surface layer on different types of terrain subject to different levels of synoptic forcing. As part of the project, a series of large field campaigns were conducted at the Dugway Proving Grounds. In winter 2014, the MATERHORN Fog-X field campaign was conducted in the Salt Lake Valley and in the Heber Valley in northern Utah.

Here are a list of important links of interest for the project:

MATERHORN Fog-X website
Fall Campaign Notes (September 24 through October 25, 2012)
Spring Campaign Notes (April 22 through May 19, 2013)
Spring Campaign Notes (April 22 through May 19, 2013)
MATERHORN Press Release

Urban Field Campaigns

SCERP (Southwestern Consortium for Environmental Research and Policy) reduction of road dust through the use of windbreaks.

  • Spatial variability of pollutants in Yuma, AZ (PhD Students H.A. Holmes, S.O. Speckart)
  • Indoor and Outdoor Pollution measurements in Nogales, MX (PhD Students H.A. Holmes, S.O. Speckart)

Joint Urban 2003: The largest Full Scale Urban field experiment ever; conducted in Oklahoma City During the Summer of 2003.

Urban Trace-gas Emissions Study (UTES) is a multidiscplinary biodiversity project funded by the National Science Foundation to investigate urban emissions of carbon dioxide and water vapor.

MUST (Mock Urban Setting Test): Large scale field experiment sponsored by the DOD and DOE. This field campagaign was run in September 2001 at the Dugway Proving grounds in western Utah. The focus of this experiments was to better characterize tranport and dispersion of plumes around buildings at very large Reynolds numbers. The experiments have provided new data sets for modelers as well as insight to the physical trasport mechanisms at work within and around the Urban Canopy.

VTMX (Vertical Transport and Mixing Experiment) October 2000 in Salt Lake City, UT. DOE sponsored project investigating vertical tranport and mixing throughout the Salt Lake Valley.

URBAN 2000 - DOE sponsored Urban field campaign (October 2000) located in Salt Lake City, UT. The experiment coincided with the VTMX experiment.

PAFEX PAFEX (Phoenix Air Flow Experiments): Two part field campaign that took place in Phoenix, Arizona. PAFEX-I (January 14-February 1, 1998). PAFEX-II (July 1-Aug 15, 1998).

Other Field Campaigns

Development of a Windbreak Dust Predictive Model and Mitigation Planning Tool:

 This SERDP (Strategic Environmental Research and Development Program) funded project has a focus of developing improved transport and deposition models. We have conducted deposition experiments in the wind-tunnel investigating the effects of turbulence on enhanced deposition to vegetative elements. The results are being used to develop generalized deposition parameterizations for use in Lagrangian transport models. The project also includes validation field experiments.

The BLLAST Experiment:

 The Boundary Layer Late Afternoon and Sunset Turbulence (BLLAST) Experiment was conducted in Lannemezan, France to investigate various atmospheric boundary layer phenomena associated with transition from the fully convective boundary layer to the nocturnal boundary layer. The EFD Team participated in the project by deploying instruments for turbulent flux measurements as well as tethered balloon meteorological measurement.

Urban Simulation Research Projects

The GEnUSiS (Green Environmental Urban Simulations for Sustainability) Project:

 Surface Temperature simulations from QUIC ENERGY

This collaborative multidisciplinary NSF funded project ran from 2011-2015 and built on previous NSF projects. The project, titled “Understanding the impact of Green Infrastructure on urban microclimate and energy use aims to develop tools to better understand urban transport physics using state of the art simulation technologies including massively parallel urban Large-Eddy Simulations, radiation and mass transport using parallel computation techniques on the GPU, as well as state of the art optimization techniques. The project is also attempting to link small-scale building resolving models with mesoscale weather models for improved prediction capability. More generally, this project addresses the critical need to improve our understanding of how Green Infrastructure (and more generally land-use and land cover change) interacts with the urban environment at the local street level scale, neighborhood scale, city scale, and mesoscales to determine the distribution of heat, moisture and pollutants.

The project also has a substanial outreach component designed to expose High School and new college students to concepts relate to atmospheric transport, Green Infrastructure, and computational modeling. For more information on our NSF Outreach project can be found here.

LOCALIZED DISTRIBUTED POWER GENERATION: ECONOMICALLY ROBUST, DEMAND-OPTIMIZED PLACEMENT OF URBAN ENERGY PRODUCTION SYSTEMS::

Distributed Energy Generation Flow Chart

Educational Outreach Projects