Flow at Ultra-High Reynolds and Rayleigh Numbers A Status Report [Paperback]

Scientists have learned to use liquid and gaseous helium to overcome the limitations imposed by the usual wind and water tunnels for testing the performance of aircraft or the behavior of the atmosphere. This book covers fundamental studies of the turbulence problem, practical applications of turbulence, superfluid turbulence, cryogenic turbulence research, and new types of miniature flow instrumentation, all which are crucial for high Reynolds number research. This state-of-the-art presentation will interest physicists in fluid dynamics, engineers working with turbulent flows, and naval and aerospace engineers testing realistic parameter ranges.Because of their extremely low viscosity, liquid helium and ultra-cold helium gas provide ideal media for fundamental studies of fluid flow and turbulence at extremely high Reynolds numbers. Such flows occur in aerospace applications (satellite reentry) and other extreme conditions, where they are difficult to study. A cryogenic-helium wind tunnel would allow one to model these flows in a laboratory at much more benign conditions. Such studies have not been feasible because, using these fluids in a wind tunnel requires more liquid helium than has readily been available. However, the capacity of the refrigerators installed at several physics laboratories that supply liquid helium for particle accelerators (such as the one intended for the SSC in Texas or the one at Brookhaven National Laboratory) is so great that some of the liquid helium or the ultra-cold helium gas may also be used for fluid dynamics studies. The chapters in this book survey the challenges and prospects for research on fluid flows at high Reynolds and Rayleigh numbers using cryogenic helium. They cover a wide range of topics: from refrigeration and instrumentation to theories of superfluid turbulence. The chapters are largely based on contributions to a workshop held at Brookhaven, but these have all been brought up to the state of the art in late 1997; in lƒ%