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The inertial range scaling of certain mixed third-order moments of velocity and magnetic field fluctuations in a turbulent MHD plasma such as the solar wind is related to the energy dissipation rate of the turbulence. We have used this relation to measure energy dissipation rates in the solar wind and other statistical methods to estimate the accuracy of these measurements. This paper reviews results we and others have recently published, and some new results. [ABSTRACT FROM AUTHOR]

The potential of cryogenic helium flows for studying high-Reynolds number turbulence in the laboratory has been recognised for a long time and implemented in several small-scale hydrodynamic experiments. With its large superconducting particle accelerators and detector magnets, CERN, the European Laboratory for Particle Physics, has become a major world center in helium cryogenics, with several large helium refrigerators having capacities up to 18 kW @ 4.5 K. Combining a small fraction of these resources with the expertise of three laboratories at the forefront of turbulence research, has led to the design, swift implementation, and successful operation of GReC (Grands Reynolds Cryogéniques) a large axisymmetric turbulent-jet experiment. With flow-rates up to 260 g/s of gaseous helium at ≈5 K and atmospheric pressure, Reynolds numbers up to 10[sup 7] have been achieved in a 4.6 m high, 1.4 m diameter cryostat. This paper presents the results of the first runs and describes the experimental set-up comprehensively equipped with "hot" wire micro-anemometers, acoustic scattering vorticity measurements and a large-bandwidth data acquisition system. [ABSTRACT FROM AUTHOR]