Changes between Version 33 and Version 34 of WikiStart

Sep 12, 2017, 7:14:28 PM (3 years ago)



  • WikiStart

    v33 v34  
    223223The bathymetry has been painted black, a pipe has been introduced into the source and the drain has been lowered to that it can be used also for 60 cm water depth.
    225 The tank is filling: $T_{water}=22.9C, $\rho=998.5 kg m!^{-3}$.
     225The tank is filling: $T_{water}=22.9C, \rho=998.5 kg m!^{-3}, T_{air} = 23C$.
     227The reflection is now ok and we can start our experiments!
     229'''Test experiment EXP01'''
     231We conducted experiments with a long HS from the beginning after turning on the influx (EXP_01). The influx was 40.67 L/min with a diaphragma of 12.6 mm diameter. The influx water had a density of 998.2 and was enriched with particles of size 30 ('''unit???'''). The laser sheet was at 11cm over the trough, 4 cm over the shelf, so at 54 cm when the laser setting was at 650. We decreased it to 640 to have the laser sheet at 55 cm. Water level was at 58.4 cm. The exposure time of the cameras was at 50ms ('''???''') and the time interval 500 ms.
     233Now we switched to the VS at 14:58 (EXP01_VERT). ('''Do we know anything about the setting there?''')
     235Afterwards we started the Scan at 15:15 (EXP01_SCAN) with the same camera settings as for the HS. The slices were at the heights of 55 cm to 30 cm in 5 cm steps. We took 4 images at each height with a time interval of 500 ms.
     237Observations: On the horizontal scans we can clearly see with our eyes that the particles are turbulent along the continental coast and don't flow straight along the continental slope. They turn left at the curvature and follow along the topography to the wall. Some particles turn right above the trough/ shelf and flow out to the slope again.
     239Data check: We checked these first results with the PIV and decided to decrease the exposure time to 40 ms to get sharper images of the particles. With PCO2, the flow around the curvature can be captured with the PIV, but on PCO1 the PIV is not very good, because the flow is more turbulent and more 3 dimensional. We decide to decrease the time between the photos. '''Later we realized that the cameras only too every second photo, so with a time interval of 1000ms! '''
     241'''Experiment EXP02'''