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Michael R Moldover

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, nist-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 and numerous awards from NIST and the US Department of Commerce.

Selected Publications


Faster, More Accurate, Stack-Flow Measurements

Aaron N. Johnson, Iosif I. Shinder, Bernard J. Filla, Joey T. Boyd, Rodney A. Bryant, Michael R. Moldover, Thomaa D. Martz, Matthew Gentry
Exhaust flows from coal-fired electricity-generating-plants are determined by measuring the flue gas velocity at prescribed points in the stack cross section


Patrick Rourke, Christof Gaiser, Roberto M. Gavioso, Michael R. Moldover, Laurent Pitre, Robin Underwood
The principles and techniques of primary refractive-index gas thermometry (RIGT) are reviewed. Absolute primary RIGT using microwave measurements of helium
Created April 2, 2019