The hot-wire process for zirconium

Hot-wire anemometry for superfluid turbulent coflows.

We report the first evidence of an enhancement of the heat transfer from a heated wire to an external turbulent coflow of superfluid helium. We used a standard Pt-Rh hot-wire anemometer and overheat it up to 21 K in a pressurized liquid helium turbulent round jet at temperatures between 1.9 K and 2.12 K. The null-velocity response of the sensor can be satisfactorily modeled by the counterflow m...

Generation and Characterization of Zirconium Carbide Nanoparticles by Wire Explosion Process

Zirconium carbide nanoparticles were produced by wire explosion process by exploding zirconium conductor in methane ambiance. X-ray diffraction studies of the particles produced by wire explosion process confirm the formation of cubic zirconium carbide particles. The results of the study indicates that unreacted zirconium content in the zirconium carbide powder could be reduced by exploding the...

The Hot - wire Anemometer for Turbulence Measurements part III

Spatial resolution correction for hot-wire anemometry in wall turbulence

We investigate spatial resolution issues in hot-wire anemometry measurements of turbulence intensity and energy spectra. Single normal hot-wire measurements are simulated by means of filtering direct numerical simulation (DNS) of turbulent channel flow at Res 1⁄4 934. Through analysis of the two-dimensional energy spectra from the DNS, the attenuation of the small-scale energy levels is documen...

Hot-wire Array for Turbulence Research in Subgrid-scale Modeling

Modeling of turbulence for Large Eddy Simulations (LES) must be based on sound understanding of the relationships between large and small scales. In order to study flows with a large range of active length-scales, high Reynolds number experimental data can be used. Thermal anemometry provides the possibility of acquiring long records of turbulence data, which are necessary for evaluating statis...