KARMAN VORTEX VELOCIMETER WITH A GENERATOR OF VERY SMALL DIAMETER

Synthesis of very small diameter silica nanofibers using sound waves.

Silica nanofibers of an average diameter ≈30 nm and length ≈100 μm have been synthesized using an unprecedented strategy: sound waves. A new phenomenon, spinning off the nanofibers at silica rod tips, is also observed.

Development of very small-diameter, inductively coupled magnetized plasma device.

In order to miniaturize a high-density, inductively coupled magnetized plasma or helicon plasma to be applied to, e.g., an industrial application and an electric propulsion field, small helicon device has been developed. The specifications of this device along with the experimental results are described. We have succeeded in generating high-density (~10(19) m(-3)) plasmas using quartz tubes wit...

Control of Karman Vortex Street behind a Thin Airfoil at Low Reynolds Number

To control the Karman vortex street formed behind a thin airfoil at a certain incidence, a control cylinder was placed at the suction side apart from the airfoil in the downstream region. Both smoke visualization and hot-wire measurements confirmed that the Karman vortex street was completely suppressed. The mechanism for suppression of the vortex street was examined with a hot-wire survey.

An Experimental Investigation of Vortex Rings and Helicopter Rotor Wakes Using a Laser Doppler Velocimeter

A New Pulse Generator with Very Fast Rise Time

instrument displays voltage changes faster than 10 9 second and has a high sensitivity of 1 millivolt. With its aid much fruitful develop ment effort has been conducted by many groups. Now, fast circuit investigations are further assisted by a versatile new pulse generator which provides pulses as short as 1 nanosecond ( 10 9 second). The pulses are provided at a high signal level of 10 volts a...