9529609 Donnelly Turbulence is undoubtedly the most outstanding unsolved problem of classical physics. From a practical turbulence is the 'limiting factor' in the design and operation of various energy systems in aeronautical, chemical and mechanical engineering. It is a central theme in geophysics, meteorology, and other areas which strongly impact human life. For these reasons, an enhanced ability to understand and predict turbulent flows will have a large payoff. This project focuses on fundamental turbulence research using a non-traditional fluid: cryogenic helium near its critical point of 5 K. Helium is theoretically capable of providing the highest Reynolds and Rayleigh number conditions for controlled turbulence experiments in a laboratory on earth. However, the working temperature range of 4-5 K presents challenges to existing techniques and instrumentation for turbulence measurements. In addition, to reach the limits of ultra-high Reynolds and Rayleigh numbers requires major cryogenic facilities which are currently found only at high energy physics projects requiring large volumes of cryogenic fluids for cooling superconducting magnets or other apparatus. This project brings together for the first time a team to meet these challenges. The team is composed of faculty at the University of Oregon (Professor Russell J. Donnelly) and Yale University (Professor Katapali R. Sreenivasan), together with co-workers (Michael S. McAshan and James R. Maddocks) who will conduct on-site research at the Brookhaven National Laboratory Relativistic Heavy Ion Collider (RHIC) Cryogenic Facility (Dr. Satoshi Ozaki, Project Director). The members of the team include world leaders in helium turbulence, fluid hydrodynamics and cryogenic technology. The project goals are to develop instrumentation for turbulence measurements using cryogenic helium, to use this instrumentation for fundamental turbulence measurements, and to construct a major convection chamber at RHIC. Successful completion of this project will place the U. S. in a world leadership position in cryogenic helium turbulence research and lay the foundation for future research in ultra high Reynolds and Rayleigh number phenomena. %%% Turbulence is undoubtedly the most outstanding unsolved problem of classical physics. From a practical turbulence is the 'limiting factor' in the design and operation of various energy systems in aeronautical, chemical and mechanical engineering. It is a central theme in geophysics, meteorology, and other areas which strongly impact human life. For these reasons, an enhanced ability to understand and predict turbulent flows will have a large payoff. This project focuses on fundamental turbulence research using a non-traditional fluid: cryogenic helium near its critical point of 5 K. Helium is theoretically capable of providing the highest Reynolds and Rayleigh number conditions for controlled turbulence experiments in a laboratory on earth. However, the working temperature range of 4-5 K presents challenges to existing techniques and instrumentation for turbulence measurements. In addition, to reach the limits of ultra-high Reynolds and Rayleigh numbers requires major cryogenic facilities which are currently found only at high energy physics projects requiring large volumes of cryogenic fluids for cooling superconducting magnets or other apparatus. This project brings together for the first time a team to meet these challenges. The team is composed of faculty at the University of Oregon (Professor Russell J. Donnelly) and Yale University (Professor Katapali R. Sreenivasan), together with co-workers (Michael S. McAshan and James R. Maddocks) who will conduct on-site research at the Brookhaven National Laboratory Relativistic Heavy Ion Collider (RHIC) Cryogenic Facility (Dr. Satoshi Ozaki, Project Director). The members of the team include world leaders in helium turbulence, fluid hydrodynamics and cryogenic technology. The project goals are to develop instrumentation for turbulence measurements using cryogenic helium, to use this instrumentation for fundamental turbulence measurements, and to construct a major convection chamber at RHIC. Successful completion of this project will place the U. S. in a world leadership position in cryogenic helium turbulence research and lay the foundation for future research in ultra high Reynolds and Rayleigh number phenomena.
