# Changes between Version 38 and Version 39 of WikiStart

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Timestamp:
Sep 14, 2017, 1:59:58 PM (3 years ago)
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 v38 ||Date Campaign Start||04/09/2017|| ||Date Campaign End||27/10/2017|| =  = =  = = ''6 - Table of Experiments: '' = =  = ||'''''Exp No.'''''||'''''Name'''''||'''''Valve opened'''''||'''''$H_{water}$'''''||'''''$T_{rot}$'''''||'''''$Q$'''''||'''''$R_{curvature}$'''''||'''''$\Delta \rho$'''''||'''''Diaphragme'''''||''''' Flowrate estimated'''''||''''' Type of photo'''''||'''''Height of HS'''''||'''''Heights of Scan and #'''''||'''''Time photo'''''||''''' Dye'''''||'''''Comments'''''||''' Notes'''|| ||||||||$(m)$||$(s)$||$(L min!^{-1})$||$(m)$||$(kg m!^{-3}$||$(mm)$||$H_1,H_2,\Delta t$||VS/HS/Scan||$cm$||$cm$||t1/t2/t3[[BR]]$\Delta t$||yes / no|||||| ||0||test||11092017 __[https://servforge.legi.grenoble-inp.fr/projects/pj-coriolis-17iceshelf/search?q=hh%3Amm hh:mm]__||0.604||50||58.5||0.50||0||13||170,150,41s||VS||-||-||?||yes||Dye did not show up in photos :-(||Elin|| ||1||exp01||12092017[[BR]]!14:38||0.584||50||40.67||0.50||0||12.6||170,150,59s||HS,VS,Scan||55||55:[-5:30,4 -5:30;4]||500ms[[BR]](reality: 1000ms)||no||Expl. time = 50 ms too little. Only every second photo was taken||Elin|| ||2||exp02||12092017[[BR]]!17:02||0.583||50||44.2||0.50||0||12.6||180,150,81.4s||HS||55?||-||200ms[[BR]](reality: 400ms)||no||Only every second photo was taken||Elin|| ||3||exp03||13092017||||50||50||0.50||0||12.6||||HS,Scan||||||200ms||no||Problem with photos fixed; particles in ambient||Elin|| ||4||exp04||13092017||||50||||0.50||0||6.8||||HS,Scan||||||200ms||no||Laser started vibrating for the scans||Elin|| =  = '''Test experiment EXP01''' We 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. Now we switched to the VS at 14:58 (EXP01_VERT). ('''Do we know anything about the setting there?''') Afterwards 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. Observations: 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. Data check: We checked these first results with the PIV and decided to decrease the exposure time 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 took every second photo, so with a time interval of 1000ms! ''' We conducted experiments with a long HS from the beginning after turning on the influx (EXP_01). The influx was 41 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 30mikrom. 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 (supervision - this changes witha few mm when People come enter/leave the rotating Office) was at 58.4 cm. The exposure time of the cameras was at 50ms  and the time interval 500 ms. We switched to the VS at 14:58 (EXP01_VERT). terwards 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. Observations: On the horizontal scans we can clearly see turbulent/vertical motion along the coast. 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. Data check: We checked these first results with the PIV and decided to decrease the exposure time 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 took every second photo, so with a time interval of 1000ms - > useless PIV.''' '''Experiment EXP02''' We repeated the HS with a reduced time to 200 ms between the photos and and exposure time of 30ms'''. We realized afterwards that the cameras only took every second photo, so with a time interval of 400ms! ''' == '''7.5 Wednesday 13 September''' == The cameras are fixed now and taking every photo and the particles are spread out in the ambient water.[[BR]]So, we start the next experiments. '''7.5 Wednesday 13 September''' The cameras are fixed now and taking every photo and the particles are spread out in the ambient water. '''Experiment EXP03''' The setup is still the same as for the previous experiments with 200ms time difference between the photos (this time working!) and particles in the ambient water. This time, we measured the flow rater AFTER the experiment and it was $Q = 50 l/min$, as expected. There are still bubbles coming out of the source! The setup is still the same as for the previous experiments with 200ms time difference between the photos (this time working!) and particles in the ambient water. This time, we measured the flow rater AFTER the experiment and it was $Q = 50 l/min$ (measurements repeated twice), as expected. There are still bubbles coming out of the source! The current reached the first corner after about 1 minute, and  the trough corner after about 3 minutes. '''Experiment EXP04''' We started a new experiment at !10:25 with a reduced flow rate of about $Q = 20 l/min$ (diaphrama diameter of 6.8 mm). The first HS is run for 15 min now. We did five more minutes of horizontal slize before we started the scan. We started a new experiment at !10:31 with a reduced flow rate of about $Q = 20 l/min$ (diaphrama diameter of 6.8 mm). The first HS is run for 15 min n(!10:31- !10:46). The flow field was still evolving so we extended the five more minutes of hs (!10:51-10:56  this data are stored in EXP04_B) before we started the scan ( !10:59). Note: During the scan, the laser is shaking too much! This needs to be changed. '''Experiment EXP05''' The vertical velocity of the laser was decreased to The vertical velocity of the laser was decreased and the timestep between the first and the second image at each level increased to 1s (first image will be discarded). The tank from where the inflow is pumped was mistakenly filled with too much Cold water (T=19.2C) - i.e. about 4 c colder than the water in the tank. There where a lot of Bubbles coming out from the Source - and we observed large (10 cm) airbubbles travelling Down the hose during the Experiment. All the water turned at the first water, onto the shelf. The current was at the first corner about 1 minute after the valve was opened. '''Experiment EXP06''' The squared cornes were inserted - the land corner was fastened with tape and the submerged corner with a screw.. To reduce to amount of Bubbles coming out from the Source we added a thin sheet of foam behind the honey comb. In addition, the joints of the tube where the diaphragm is inserted was greased. This appeared to help - the amound of Bubbles was greatly reduced and no Bubbles was seen travelling Down the hose. The flow separated at the first corner and turned at the second corner. The vertical scann was started 15 min after the valve was opened. '''Experiment EXP07''' An eddy initially forms behind the first corner, but it then disappears. The flow turns into the through. Large eddy on the Continental shelf (as in Kjerstis model Experiments!). When scanning dt was set to 100 ms, but only every second photo was aquired so dt= 2 x 100. '''7.6 Wednesday 13 September''' ''6 - Table of Experiments: '' - will be updated from Excel sheet! ||'''''Exp No.'''''||'''''Name'''''||'''''Valve opened'''''||'''''$H_{water}$'''''||'''''$T_{rot}$'''''||'''''$Q$'''''||'''''$R_{curvature}$'''''||'''''$\Delta \rho$'''''||'''''Diaphragme'''''||''''' Flowrate estimated'''''||''''' Type of photo'''''||'''''Height of HS'''''||'''''Heights of Scan and #'''''||'''''Time photo'''''||''''' Dye'''''||'''''Comments'''''||''' Notes'''|| ||||||||$(m)$||$(s)$||$(L min!^{-1})$||$(m)$||$(kg m!^{-3}$||$(mm)$||$H_1,H_2,\Delta t$||VS/HS/Scan||$cm$||$cm$||t1/t2/t3[[BR]]$\Delta t$||yes / no|||||| ||0||test||11092017 __[https://servforge.legi.grenoble-inp.fr/projects/pj-coriolis-17iceshelf/search?q=hh%3Amm hh:mm]__||0.604||50||58.5||0.50||0||13||170,150,41s||VS||-||-||?||yes||Dye did not show up in photos :-(||Elin|| ||1||exp01||12092017[[BR]]!14:38||0.584||50||40.67||0.50||0||12.6||170,150,59s||HS,VS,Scan||55||55:__[-5:30,4 -5:30;4]__||500ms[[BR]](reality: 1000ms)||no||Expl. time = 50 ms too little. Only every second photo was taken||Elin|| ||2||exp02||12092017[[BR]]!17:02||0.583||50||44.2||0.50||0||12.6||180,150,81.4s||HS||55?||-||200ms[[BR]](reality: 400ms)||no||Only every second photo was taken||Elin|| ||3||exp03||13092017||||50||50||0.50||0||12.6||||HS,Scan||||||200ms||no||Problem with photos fixed; particles in ambient||Elin|| ||4||exp04||13092017||||50||||0.50||0||6.8||||HS,Scan||||||200ms||no||Laser started vibrating for the scans||Elin||