Laser PIV System

Specification of Laser PIV System

Laser:

• Solid-state air- cooled 200 mW, 660 nm laser diode (Class 3b).
• Standard optics produce a c. 3 mm thick, 45° light sheet (c. 200 mm wide at 250 mm).
• Interchangeable 20° light sheet optic available (item H41-3).
• Pulse separation (t) of between 100 µs - 5 s (in steps of 10 µs).
• Pulse width of between 10 µs - 32 ms (in steps of 10 µs).

Camera:

• Super-sensitive VGA CMOS sensor:
• 640 — 480, 6.0 µm pixels (1/3?? format);
• ~50% quantum efficiency at 660 nm;
• 75 - 110 dB dynamic range;
• 4.8 V/lux·sec sensitivity.
• Trigger input enables image pair acquisition to be synchronised with external events.
• Accepts standard CS- or C-mount lenses (12.5mm f/1.4 lens supplied).
• Camera exposure can be linked to the lasers pulsing, thereby enabling operation in a lit room.

Software Processing:

• Data refresh and recording rate up to 16Hz (dependent on the computer speed, the selected acquisition and PIV analysis parameters and the recording taking place)
• Real-time, or offline, 2-component vector calculation.
• Single pass or adaptive multi-pass cross-correlation with 8, 12, 16, 24, 32 or 64 pixel window sizes.
• 0% or 50% window overlap (i.e. maps of up to 19,000 vectors).
• Optional vector interpolation and filtering

Based On:

• User-supplied velocity limits;
• RMS of neighbouring vectors values.
• Calculation of the following derived scalars:
• Vector angle and magnitude;
• Vorticity and swirl;
• Time-averaged mean velocity;
• RMS and turbulence intensity.
• Where applicable, vector component and statistical sample number are user-defined