Timothy J. O’Hern

Sandia National Laboratories California

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J. R. Torczynski

Sandia National Laboratories

K.A. Shollenberger

California Polytechnic State University

Steven L. Ceccio

University of Michigan–Ann Arbor

Bion Shelden

Sandia National Laboratories

Jonathan Clausen

Sandia National Laboratories California

S. M. Trujillo

Sandia National Laboratories California

Paul Tortora

Carnegie Mellon University

Louis A. Romero

University of Padua

Nicholas B Wyatt

University of Birmingham

Sheldon R. Tieszen

Sandia National Laboratories

Cooperative Institutions

Sandia National Laboratories

123

Sandia National Laboratories California

105

Bioengineering Center

National Center for Genetic Engineering and Biotechnology

Office of Scientific and Technical Information

National Technical Information Service

Oak Ridge National Laboratory

University of Michigan–Ann Arbor

University of New Mexico

Radiology Associates of Albuquerque

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Experiments to Estimate Polyurethane Foam Reaction Kinetics.

Lisa Ann Mondy Rekha R. Rao Mathias C. Celina Bion Shelden Nicholas B Wyatt

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Advances in process intensification through multifunctional reactor engineering.

Marcia A. Cooper James E. Miller Timothy J. O’Hern Walter Gill Lindsey Evans

A multifunctional reactor is a chemical engineering device that exploits enhanced heat and mass transfer to promote production of a desired chemical, combining more than one unit operation in a single system. The main component of the reactor system under study here is a vertical column containing packing material through which liquid(s) and gas flow cocurrently downward. Under certain conditions, a range of hydrodynamic regimes can be achieved within the column that can either enhance or inhibit a desired chemical reaction. To study such reactors in a controlled laboratory environment, two experimental facilities were constructed at Sandia National Laboratories. One experiment, referred to as the Two-Phase Experiment, operates with two phases (air and water). The second experiment, referred to as the Three-Phase Experiment, operates with three phases (immiscible organic liquid and aqueous liquid, and nitrogen). This report describes the motivation, design, construction, operational hazards, and operation of the both of these experiments. Data and conclusions are included.

Chemical reactor

10.2172/1011212

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Adding Some Gas Can Completely Change How an Object in a Liquid-Filled Housing Responds to Vibration

Bulletin of the American Physical Society (2015)

J. R. Torczynski Timothy J. O’Hern Jonathan Clausen

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First-Principles Flocculation as the Key to Low Energy Algal Biofuels Processing.

OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) (2011)

John C. Hewson Patrick V. Brady Brian P. Dwyer Anne Grillet Lindsey Gloe Hughes

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Detail Investigation of Solute Mixing in Pipe Joints Through High Speed Photography.

OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) (2008)

Sean Andrew McKenna Timothy J. O’Hern Joel Hartenberger

High-speed photography

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Joint physical and numerical modeling of water distribution networks.

Adam Zimmerman Timothy J. O’Hern Leslie Orear Karen Kajder Stephen Webb

This report summarizes the experimental and modeling effort undertaken to understand solute mixing in a water distribution network conducted during the last year of a 3-year project. The experimental effort involves measurement of extent of mixing within different configurations of pipe networks, measurement of dynamic mixing in a single mixing tank, and measurement of dynamic solute mixing in a combined network-tank configuration. High resolution analysis of turbulence mixing is carried out via high speed photography as well as 3D finite-volume based Large Eddy Simulation turbulence models. Macroscopic mixing rules based on flow momentum balance are also explored, and in some cases, implemented in EPANET. A new version EPANET code was developed to yield better mixing predictions. The impact of a storage tank on pipe mixing in a combined pipe-tank network during diurnal fill-and-drain cycles is assessed. Preliminary comparison between dynamic pilot data and EPANET-BAM is also reported.

Momentum (technical analysis)

Large-Eddy Simulation

Mixing patterns

Code-mixing

10.2172/961658

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Experimental Study of the Solids Velocity Field in Gas−Solid Risers

Industrial & Engineering Chemistry Research (2005)

Satish Bhusarapu Muthanna H. Al‐Dahhan Milorad P. Duduković S. M. Trujillo Timothy J. O’Hern

Solids flow dynamics in gas−solid risers is inherently complex. Model refinement through experimental validation requires the acquisition of detailed nonintrusive measurements. In this study, noninvasive computer-automated radioactive particle tracking (CARPT) is employed to visualize and quantify in a three-dimensional domain the solids dynamics and mixing in gas−solid risers. This technique has the added advantage that, along with the derived Eulerian solids flow field (time-average velocity map and various turbulence parameters such as the Reynolds stresses, turbulent kinetic energy), it also provides directly the Lagrangian description of the solids motion. The solids velocity field data are obtained in two different risers at low and high solids fluxes at varying superficial gas velocity to span both the fast-fluidized (FF) and dilute phase transport (DPT) regimes. The effect of operating conditions on solids flow and mixing is studied. Comparative analysis of the results is presented to provide insights into the complex solids flow patterns characteristic of gas−solid risers.

Reynolds stress

10.1021/ie050297f

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Citations (38)

Gamma-densitometry tomography of gas holdup spatial distribution in industrial-scale bubble columns

Chemical Engineering Science (1997)

K.A. Shollenberger J. R. Torczynski Douglas R. Adkins Timothy J. O’Hern Nancy B. Jackson

TRACER

10.1016/s0009-2509(97)00032-8

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Citations (102)

In situ measurement of particle formation in heated jet fuels―A new application of photon correlation spectroscopy