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Michael R Moldover (Assoc)

For 50+ years, Dr. Michael Moldover and his collaborators have measured the thermophysical properties of fluids to solve scientific and engineering problems and to improve standards of temperature, pressure, and flow. Moldover invented quasi-spherical cavity resonators; NIST and others used them to make the best-in-the-world measurements of the Boltzmann constant and of the thermodynamic temperature from 7 K to 550 K. For fluids near critical points, Moldover measured the singularities of the heat capacity, equation of state, speed-of-sound, surface tension, shear viscosity, and bulk viscosity. Some of these challenging measurements were conducted in the microgravity environment provided by the Space Shuttle. Moldover demonstrated the ubiquity of critical-point wetting. He stimulated a 100-fold improvement in the accuracy of fundamental-physics-based calculations of the thermophysical properties of helium; now, the calculated values are used to calibrate instruments that measure such properties. Under Moldover's leadership, NIST's Fluid Metrology Group has measured the thermophysical properties of replacements for ozone-layer-damaging refrigerants and the properties of reactive gases used in semiconductor processing. Now, the Group is improving standards for calibrating flow meters, measuring the carbon dioxide emitted by coal-burning power plants, and accurately measuring the flow of hydrogen into next-generation automobiles when they are refueled.

Dr. Moldover is a NIST Fellow and a Fellow of both the American Physical Society and the Acoustical Society of America. He received the Touloukian Award from the ASME, the Helmholtz-Rayleigh Interdisciplinary Silver Medal from the Acoustical Society of America and numerous awards from NIST and the US Department of Commerce.

Selected Publications


Ab initio Calculation of Fluid Properties for Precision Metrology

Giovanni Garberoglio, Christof Gaiser, Roberto Maria Gavioso, Allan H. Harvey, Robert Hellmann, Bogumil Jeziorski, Karsten Meier, Michael R. Moldover, Laurent Pitre, Krzysztof Szalewicz, Robin Underwood
Recent advances regarding the interplay between ab initio calculations and metrology are reviewed, with particular emphasis on gas-based techniques used for

Non-nulling Protocols for Fast, Accurate, 3-D Velocity Measurements in Stacks

Iosif Isaakovich Shinder, Aaron Johnson, James Filla, Vladimir B. Khromchenko, Michael R. Moldover, Joey Boyd, John D. Wright, John R. Stoup
We present protocols for making fast, accurate, 3-D velocity measurements in the stacks of coal-fired power plants. The measurements are traceable to

Gas Flow Standards and Their Uncertainty

John D. Wright, Aaron Johnson, Michael R. Moldover, Shin-ichi Nakao
We review diverse types of gas flow standards that are used to calibrate other gas flow meters. For each type of standard, we describe the principles of its

Thermal Boundary Layers in Critical Flow Venturis

John D. Wright, Aaron Johnson, Michael R. Moldover, Woong Kang, Liang Zhang, Bodo Mickan
We improve the usefulness of small (diameter 10 mm) critical flow venturis (CFVs) as transfer standards for gas flow by measuring and explaining how their
Created April 2, 2019, Updated December 8, 2022