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...

In this study, nanofluids of Chromium (Cr) in water, Ethylene Glycol and Ethanol have been prepared using single step method. The thermal conductivity and diffusivity of these nanofluids were measured via hot wire-photothermal deflection technique. Based on finite difference method (FDM) temperature distribution and photothermal deflection caused by the hot wire inside nanofluids was obtained. ...

Injecting a gas into fusion reactors or semiconductor manufacturing systems, one has to quickly control the flow rate by a piezoelectric valve. In order to construct a gas injection system with high speed valves in the future, performance tests have been conducted on a commercial piezoelectric valve. An orifice flowmeter for measuring time average flowrate and a hot wire anemometer for instanta...

The transient hot-wire method has been widely used to measure the thermal conductivity of fluids. The ideal working equation is based on the solution of the transient heat conduction equation for an infinite linear heat source assuming no natural convection or thermal end effects. In practice, the assumptions inherent in the model are only valid for a portion of the measurement time. In this st...

Microcrystalline silicon (mc-Si:H) and amorphous silicon (a-Si:H) films were deposited using a hot-wire CVD (HWCVD) system that employs a coiled filament. Process gasses, H and Si H , could be directed into the deposition chamber via different 2 2 6 gas inlets, either through a coiled filament for efficient dissociation or into the chamber away from the filament, but near the substrates. We fou...

This paper presents, the experimental study has been made to optimize the process parameters during machining of H-13 by wire electrical discharge machining (WEDM) using Taguchi L9 orthogonal array method. Following input process parameters of WEDM [Pulse-On time (TON), Pulse-Off time (TOFF) and Wire Speed rate (WS) and Wire Tension (WT)] were chosen as variables to study the process output in ...