New to the lab is a state of the art LaVision Particle Image
Velocimetry/Laser Induced Fluorescence (PIV/LIF) system. The
imaging system consists of two 4M pixel, 14 bit, dual-frame
video cameras. The cameras each have 2GB of onboard RAM and
are capable of 14.7 frames per second. Light sheet illumination
is from a Big Sky 200mJ Nd:YAG dual head laser with a 30Hz
repetition rate. The system is controlled from a dual processor
PC with a 1 terabyte RAID array for image logging. The LaVision
PIV/LIF system and software can be used for planar 2D, 3D
(out of plane) PIV data, or simultaneous 2D PIV and LIF.
The PIV/LIF system is available for general use in the GFD
lab, but special accommodations have been made for its use
on the new 1-meter rotating table. These include a sturdy
framework on the table for mounting the laser and cameras,
and a translation stage for vertical positioning of the light
sheet and cameras. The digital video camera signals are brought
off the table through a fiber optic slip ring. This allows
the acquisition and control computer to sit off the rotating
table for ease of use during table rotation.
Conductivity and Temperature probes
The lab has six Precision Measurement Engineering micro-scale
conductivity probes. Two of these probes have thermistors
for co-incident temperature and conductivity measurements.
The probes are routinely used for profiling being moved vertically
or horizontally by precision stepper motors. With a time constant
faster than 10-1 s , the probe can routinely measure microstructure
down to a mm length scale.
The lab has two multi-axis translation stages for conductivity
profiling. One is a 3D system designed to provide x-y-z profiling
capabilities over most of the two-meter table (176 cm x 176
cm x 50 cm motion envelope). The second system is a x-z stage
(100cm x 50 cm motion envelope). Both systems use stepper
motors with multi-axis controllers from Parker-Compumotor.
In addition, several older single-axis stages are available.
Two Anton-Paar Density Meters are available for precise density
measurements. One is precise to 0.01 kg/m3 and the other to
0.1 kg/m3 .
Standard color and black and white analog video cameras and
a suite of C-mount lenses are available. In addition, the
GFD lab has several megapixel digital video cameras (aside
from the PIV system cameras). These include two Hitachi KPF-120
black and white cameras (1.4M pixel, 30 fps, 10 bit) and one
Hitachi KPF-100C color camera (1.4 M pixel, 15 fps). Two image
capture computers are used for direct-to-computer image sequence
capture using EPIX XCAP software. A Nikon D1 digital camera
is available for still photography. Video monitors and VCRs
are in each lab location.
The lab routinely uses the latest versions of MatLab and
Photoshop. Video data analysis software includes Digiflow,
EPIX-XCAP, and the LaVision PIV/LIF software mentioned above.
Experiment specific software has been written for stepper
motor control, data acquisition, and conductivity profiling.
Related Equipment & Facilities
- Precise thermostatic baths (NESLAB)
- Stepper motors and controllers
- Spectra-Physics 6W Argon-Ion laser
- Programmable temperature loggers
- A collection of dyes, particles, pumps, filters,
thermometers, hydrometers, glassware and flow meters.
- Seawater and seawater drains available in the Coastal
- Custom designed tanks and apparatus built in-house
- Machine shop in Coastal Research Laboratory