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8.2
Dynamic mode
This mode captures a video sequence showing the dynamic interaction
between the liquid and the surface. Here the dynamic wetting (contact
angle), liquid penetration (volume) and spreading is measured as a function
of time. After a droplet has been pumped out at the dispensing tip, a new
test is started when the Measure button is pressed. The droplet must then be
applied on the specimen surface within 30 seconds.
In Dynamic Mode the droplet cannot be applied “slowly onto the surface” as
in Static Mode.
Such a slow application would make the initial interaction during the first
second impossible to measure. Instead the droplet is gently transferred to the
surface from a very short “free-fall” distance.
8.2.1 Parameters
Auto Method
Off
Manual
test
Volume
Automatic test with droplet size control
Time
Automatic test with time control
Droplet Size
Enable only if the Auto Method is selected to Volume
Time Pump
Enable only if the Auto Method is selected to Time
Drop Application Mode
Impact
The pendant droplet is lifted and dropped
with a small impact.
Touch Down
The pendant droplet is lowered towards
the
surface.
Delay Trigger
The measurement is suspended until the set time has expired.
Disable when the Auto Method is selected to Off.
Duration
Duration test.
Liquid
It has no influence in the results.
Sample Rate
It’s the number of frame per second that the camera will collect.
