Changes between Version 23 and Version 24 of WikiStart


Ignore:
Timestamp:
Sep 12, 2017, 10:15:54 AM (3 years ago)
Author:
darelius4e
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • WikiStart

    v23 v24  
    164164The table starts rotating for the first time with a velocity of 50 rounds/ sec. It gets slowly filled with water to a level of 60 cm. This takes about 3h. Before we can start the experiments, the lasers first have to be adjusted. To check how long the water stays in the water, we conduct a little experiments with water (from the tank) that is enriched with particles. After about 2 hours a 4 mm thick clear surface layer develops.
    165165
    166 ''First day of experiment ! We have many difficulties to get an homogeneous distribution of particles at the level of the laser sheet (located in the dense lower layer). We first spray at the surface the particles (30 microns, 1013 g/l) diluted with quite dense salty water. But after waiting one hour the particles never reach the level of the laser sheet... Hence, in order to be able to visualize something we started to inject directly inside the lower layer with the sprayer. We then succeed to disperse high concentration of particles at the level of the laser sheet.''
     166After filling the tank Thoma measured the water level to be
     167point where water level does not change with rotation 60.4 cm
     168Center of tank – 42.5 + 16 cm = 58.5 cm
     169Tank wall (6.5 m) – 62.4 cm
    167170
    168 ''Three test experiments were performed with the oscillatory flap.''
    169171
    170 '''''EXP01''': '''Oscillation''' period 200s, very poor repartition of particles and hard to distinguish the global flow structure.''
     172Particle sedimentation test
     173Water was taken from the tank, mixed with particles (+ wetting agent) and set to settle in a glass “vase” with a narrow (ca 3cm) and tall (ca 10 cm) neck. The upper level with particles were observed at roughly 30 min intervals.
     174|| Time || level ||
     175||11:50|| 0 ||
     176||13.05||4mm||
     177||13.30||5 mm|| 
    171178
    172 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    173 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    174 ||''PCO''||''after carriage''||''100ms''||''0.1''||''?''||''?''||''''''''''||
     179'''Calibration of vertical laser sheet'''
    175180
    176 ''Laser parameters''
     181While changing the settings on the laser, the actual height of the laser sheet was measured directly in the tank.
    177182
    178 ||'''''Laser'''''||'''''Intensity'''''||'''''angle'''''||'''''d-3'''''||''''''''''||''d-2''''''''||''d-1''''''''||''d0''''''''||''d1''''''''||''d2''''''''||''d3''''''''||
    179 ||''$(nm)$''||''$(Watt)$''||''$(°)$''||''$(cm)$''||''''''''''||''$(cm)$''||''$(cm)$''||''$(cm)$''||''$(cm)$''||''$(cm)$''||''$(cm)$''||
    180 ||''532''||''25''||''60''||''''''''''||'||''''''''''||'||''''''''''||'||'||'||
     183'''|| Laser setting || $H_{real} ||'''
     184||650|| 55 cm ||
     185||700|| 49.5 cm||
     186||800|| 40 cm ||
     187||850 || 35 cm ||
     188||900 || 30 cm ||   
    181189
    182 '''''EXP02''': '''Oscillation''' period 100s, we starts to see some oscillation in the flow that propagates along the wall. A large-scale shear flow seems to establish along the shelf.''
     190We will use 650 :50: 900 to get Slices every 5 cm from 30 cm to 55 cm (total 6 Slices).
    183191
    184 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    185 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    186 ||''PCO''||''after carriage''||''50ms''||''0.5''||''?''||''?''||''''''''''||
    187192
    188 '''''EXP03''': '''Oscillation''' period 100s, reduced oscillation amplitude''
    189193
    190 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    191 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    192 ||''PCO''||''after carriage''||''50ms''||''0.5''||''?''||''?''||''''''''''||
    193194
    194 '''''Thursday, February 16th 2017'''''
    195 
    196 ''The repartition of particles over the tank is better when we arrive in the morning. During all the day, particles are added at the level of the laser beam following the same method than the previous day. The laser angle was changed from 60° to 75 °.   Three interdependent parameters of the carrier can be tuned to set the forcing of the oscillating flat: T_flap, A_flap and Vmax_flap. We choose to set Vmax_flap to 3 cm/s to improve the comparison with the MITgcm simulations.  Four experiments with different amplitudes and periods were performed to study the sensibility of the formation of topographic wave. In these experiments, we do not stop the record of the camera when we stop the flap to record what happen when the forcing is stopped.''
    197 
    198 '''''EXP04''': '''Oscillation''' period 60s''
    199 
    200 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    201 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    202 ||''PCO''||''after carriage''||''50ms''||''0.1''||''?''||''?''||''''''''''||
    203 
    204 ''Laser parameters''
    205 
    206 ||'''''Laser'''''||'''''Intensity'''''||'''''angle'''''||'''''d-3'''''||''''''''''||''d-2''''''''||''d-1''''''''||''d0''''''''||''d1''''''''||''d2''''''''||''d3''''''''||
    207 ||''$(nm)$''||''$(Watt)$''||''$(°)$''||''$(cm)$''||''''''''''||''$(cm)$''||''$(cm)$''||''$(cm)$''||''$(cm)$''||''$(cm)$''||''$(cm)$''||
    208 ||''532''||''25''||''75''||''''''''''||'||''''''''''||'||''''''''''||'||'||'||
    209 
    210 '''''EXP05''': '''Oscillation''' period 40s''
    211 
    212 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    213 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    214 ||''PCO''||''after carriage''||''50ms''||''0.5''||''?''||''?''||''''''''''||
    215 
    216 '''''EXP06''': '''Oscillation''' period 80s''
    217 
    218 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    219 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    220 ||''PCO''||''after carriage''||''50ms''||''0.5''||''?''||''?''||''''''''''||
    221 
    222 '''''EXP07''': '''Oscillation''' period 20s''
    223 
    224 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    225 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    226 ||''PCO''||''after carriage''||''50ms''||''0.5''||''?''||''?''||''''''''''||
    227 
    228 ''At the end of the day, we want to perform an experiment with the laser in the upper layer but the upper limit of the laser is inside the layer of transition between the upper and lower layer. Consequently, it changes the angle of the laser due to the refraction of the beam into the inhomogeneous layer. This upper limit is fixed by the position of the mirror on which the laser beam is reflected that need to be moved when the tank is empty.''
    229 
    230 '''''Friday, February 17th 2017'''''
    231 
    232 ''This day is dedicated to the formation of the coastal current in the upper layer.''
    233 
    234 ''For the moment, the control of the flow rate is complicated. It can be done by tuning the opening of one valve and estimating the flow rate in the tanks above the platform. It is done by looking at the evolution of the water levels at during 1 minute given by a stopwatch. This is not precise and it takes time to reach the flow rate targeted. We have to build and test some diaphragms to reduce the size of the pipe. Each diagram will be associated with a flow rate which will be constant.''
    235 
    236 ''There is no laser in the upper layer. The particles are directly mixed with the water in the tanks above the platform before their injection in the surface layer. These particles are lighted by the diffusion of the laser from below. Consequently, it is possible to see the water added by the injectors into the upper layer but all the other part of this layer are not visible. Indeed, the signal of the particle at the depth of the laser beam (i.e. in the lower layer) is too strong. This is a main problem that has to be changed by moving up the mirror which reflect the laser.''
    237 
    238 ''The stratification is not very good when filling from the bottom of the tank. The process will consequently be changed. The tank will firstly be filled with the salty water. The upper layer will be added directly into the surface layer using diffusers.''
    239 
    240 ''The laser stopped by itself during the experiment 8. This happened also shortly after the beginning of an experiment we did not save as no water injected had not enough time to reach the camera field-of-view. The problem comes from the tarpaulin of the platform which is close to the fan of the laser cooler. This blocks the evacuation of the air and increase the temperature inside the laser device. To prevent any damage, the laser is automatically shut down when a maximum temperature is reached. Now, the tarpaulin is open behind the cooler but it results in a hole letting the air to enter inside the platform. Moreover, the fan of the cooler might warm the water surface locally which can perturb the upper surface. Consequently, the cooler has to be put outside the tarpaulin to prevent all these effects.''
    241 
    242 ''The exit of the injector is not along the wall as it exists a gap of 20.5 cm. A large amount of the water injected turn to the right when it is injected and do not flow along the wall. This effect reduces when the flow rate is increased. It needs a flow rate by far superior (30 l/min) than what it was planned (7 l/min). Moreover, the separation of the flow due to the geometry adds a lot of perturbation that lead to the creation of large eddies. For example, a large cyclonic eddy stays close to the exit of the injector for a flow rate of 7l/min. We need to prevent this effect adding a wall between the onshore part of the injector and the wall.  This solution was tested with a wooden sheet hold by hand which seems to drastically reduce this effect. A fixed one will be added when the platform will be empty on Monday.''
    243 
    244 ''All the different problems mentioned before will be solved when the platform will be empty on Monday. Three experiments were performed but, as the flow is perturbed in many ways, we do not think that it will be representative of the flow when the different problems will be solved.''
    245 
    246 '''''EXP08''': '''Injection''' flow rate 7.2 l/min''
    247 
    248 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    249 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    250 ||''PCO''||''after carriage''||''50ms''||''0.5''||''?''||''?''||''''''''''||
    251 
    252 '''''EXP09''': '''Injection''' flow rate 7.4 l/min''
    253 
    254 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    255 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    256 ||''PCO''||''after carriage''||''50ms''||''0.5''||''?''||''?''||''''''''''||
    257 
    258 '''''EXP10''': '''Injection''' flow rate 35.3 l/min to 60 l/min. We increased the flow rate from 35.3 l/min to 60 l/min after XXXX minutes of recording the see its impact on the formation of the coastal current.''
    259 
    260 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    261 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    262 ||''PCO''||''after carriage''||''50ms''||''0.5''||''?''||''?''||''''''''''||
    263 
    264 '''''Monday, February 20th 2017'''''
    265 
    266 ''The platform is empty in the morning.''
    267 
    268 ''The day begins by the calibration of the two CTD sensors using 7 samples which span from 998.6 to 1025.1 kg/m3. One 2nd order polynomial regression is applied for each of them to define the relation between the voltage measured and the water density. The profiles obtained are presented in the following figure.''
    269 
    270 ''[[Image(http://img11.hostingpics.net/pics/702568Profilesweek1.png)]]''
    271 
    272 ''All the distance between each element of the experimental setup and the point of reference along the wall are measured. A schematic of the setup of the first week called smooth shelf configuration is presented in the following figure.''
    273 
    274 ''[[Image(http://img11.hostingpics.net/pics/181661Setup1.png)]]''
    275 
    276 ''The three downstream plastic sheets were removed to replace them by a triangle which make the transition between the slope and the flat floor. Along the wall, it results in 6.75m of constant shell, 2.74m of transition and 3.27m of flat bottom.''
    277 
    278 ''The calibration of two of the three fixed cameras is also done using a target of 2mx2m in the field of view of each of them. Firstly, the target is kept horizontal for the first pictures. Then, it is moved in all directions to have a 3D representation of the target that help to correct the picture. This calibration is not done for the camera recording the flap and the injector as we did not succeed to have a clear picture in the computer.''
    279 
    280 ''We saw last week that a lot of turbulence is created at the exit of the injector. A schematic of what was observed is presented in the following figure.''
    281 
    282 ''[[Image(http://img11.hostingpics.net/pics/367738Currentreturn.png)]]''
    283 
    284 ''To prevent these perturbations, the shelf is extended and now the exit of the injector is above the shelf to ensure that the water flow directly above it. Secondly, a vertical plastic sheet that link the exit of the injector and the wall is added. We hope that this will prevent the return of the current below the injector and will help the injected water to reach directly the vertical wall.''
    285 
    286 '''''Tuesday, February 21th 2017'''''
    287 
    288 ''The position of the carrier is changed. The flap is now linked to the downstream edge of the carrier to improve the field of view in the cameras upstream of the transition area.''
    289 
    290 ''The laser length is now changed to 90°. The mirror of the laser is also lifted of 8cm to have the laser sheet in the upper homogeneous layer. The laser device is also rotated to have enough light both over the transition area and over the flat bottom.''
    291 
    292 ''All the distance between each element of the second experimental are measured. A schematic of the setup of the second week in the canyon configuration is presented in the following figure.''
    293 
    294 ''[[Image(http://img11.hostingpics.net/pics/189036Setup2.png)]]''
    295 
    296 ||''Position''||''M2''||''M1''||''M0''||''M-1''||''M-2''||
    297 ||''H_coast (cm)''||''''''''''||'||''18''||''''''''''||'||
    298 ||''H_laser_up (cm)''||''''''''''||'||''''''''''||'||''''''''''||
    299 ||''H_laser_down (cm)''||''''''''''||'||''''''''''||'||''''''''''||
    300 
    301 '''''Wednesday, February 22th 2017'''''
    302 
    303 ||''Position''||''M2''||''M1''||''M0''||''M-1''||''M-2''||
    304 ||''H_coast (cm)''||''19.7''||''19''||''18''||''18.5''||''19''||
    305 ||''H_laser_up (cm)''||''/''||''/''||''/''||''/''||''/''||
    306 ||''H_laser_down (cm)''||''9.5''||''3.5''||''4''||''7.3''||''/''||
    307 
    308 ''A CTD profile recorded this morning can be compared to the one recorded at the end of the day yesterday in the following figure : [[Image(http://img11.hostingpics.net/pics/644040Profilesweek2.png)]]''
    309 
    310 ||''Position''||''M2''||''M1''||''M0''||''M-1''||''M-2''||
    311 ||''H_coast (cm)''||''19''||''18''||''18.5''||''18''||''18.8''||
    312 ||''H_laser_up (cm)''||''/''||''/''||''/''||''/''||''/''||
    313 ||''H_laser_down (cm)''||''6''||''2.5''||''3.5''||''5''||''/''||
    314 
    315 ''Bottom density => 1009.5 (T 20.9) Surface density => 1002 (T 19.9)''
    316 
    317 ||''Lumenera[[BR]]Settings''||''mean_dt[[BR]](ms)''||''mean_dx[[BR]](pix/mm)''||''Area[[BR]](pix/pix)''||''exposure[[BR]](ms)''||''contrast''||''brightness''||''gain''||
    318 ||''EXP12''||''283''||''1.83''||''4000x1600''||''200''||''2.33''||''39''||''4.43''||
    319 ||''EXP13''||''283''||''1.83''||''4000x1600''||''200''||''2.33''||''39''||''4.43''||
    320 ||''EXP14''||''545-560''||''1.83''||''4000x1600''||''200''||''2.33''||''39''||''4.64''||
    321 
    322 '''''Thursday, February 23th 2017'''''
    323 
    324 ||''Position''||''M2''||''M1''||''M0''||''M-1''||''M-2''||
    325 ||''H_coast (cm)''||''19''||''18.7''||''18''||''18''||''18.5''||
    326 ||''H_laser_up (cm)''||''/''||''/''||''/''||''/''||''/''||
    327 ||''H_laser_down (cm)''||''/''||''6.6''||''3.4''||''2.5''||''/''||
    328 
    329 ''Changeemnt de sonde aprés EXP15, C0 est déplacé et maintenant devient C2. La nouvelle sonde C0 est à la place de l'ancienne C0. Surface nouvelle C0/TO 371 surface libre. C2 est ajoutée aux données lors de l'expérience 17. Le gain de cette dernière est modifié aprés 5min de cette même expérience.''
    330 
    331 ||''Lumenera[[BR]]Settings''||''mean_dt[[BR]](ms)''||''mean_dx[[BR]](pix/mm)''||''Area[[BR]](pix/pix)''||''exposure[[BR]](ms)''||''contrast''||''brightness''||''gain''||
    332 ||''EXP15''||''550-560''||''1.83''||''4000x1600''||''200''||''3.26''||''39''||''4.43''||
    333 ||''EXP16''||''550-560''||''1.83''||''4000x1600''||''200''||''3.26''||''39''||''7-9''||
    334 ||''EXP17''||''570''||''1.83''||''4000x1600''||''200''||''3.26''||''39''||''13''||
    335 
    336 '''''Friday, February 24th 2017'''''
    337 
    338 ''Position of the flap changed in the morning. A schema of the two positions is given in the following figure.''
    339 
    340 ''[[Image(http://img11.hostingpics.net/pics/873471FlapPositions.png)]]''
    341 
    342 ||''Lumenera[[BR]]Settings''||''mean_dt[[BR]](ms)''||''mean_dx[[BR]](pix/mm)''||''Area[[BR]](pix/pix)''||''exposure[[BR]](ms)''||''contrast''||''brightness''||''gain''||
    343 ||''EXP18''||''576''||''1.83''||''4000x1600''||''220''||''3.26''||''39''||''3.64''||
    344 ||''EXP19''||''576''||''1.83''||''4000x1600''||''220''||''3.26''||''39''||''3.9''||
    345 ||''EXP20''||''577''||''1.83''||''4000x1600''||''220''||''3.26''||''39''||''3.9''||
    346 ||''EXP21''||''599''||''1.83''||''4000x1600''||''220''||''3.26''||''38.6''||''7''||
    347 
    348 '''''EXP18''': '''Oscillation'''''
    349 
    350 ''Problem of data recording with the PCO camera during the experiment 18. First 4'35 of the record were not stored due to a lack of disk space.''
    351 
    352 ''We stopped the recording before the end of the experiment as the number of particles was not sufficient.''
    353 
    354 '''''EXP19''': '''Oscillation'''''
    355 
    356 '''''EXP21''': '''Oscillation'''  period 80s''
    357 
    358 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    359 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    360 ||''PCO/FALCON/Lumenera''||''before carriage''||''50ms''||''0.3''||''?''||''?''||''''''''''||
    361 
    362 [[BR]]'''''Monday, February 27th 2017'''''
    363 
    364 ''The extraction of the surface layer during the weekend did not succeed. 15 cm of water was extracted but there is still a stratification on the profiles.''
    365 
    366 ''The remaining water is mixed by hand and the 15 last centimetres are added using water with the density of the bottom layer. The final density is 1009.1 g/m!^3 at 20.2°C. The difference of height with two layers stratification is less than 1 mm.''
    367 
    368 ''Checked the horizontal of the laser sheet.Change the flat position to have its reference perpendicular to the wall.''
    369 
    370 ''The mixing of the water re-suspend the particles in all the water column. The repartition is now homogeneous but they are in all different layers but not only at the position of the laser sheet. The resulting pictures are less complicated to interpret by eyes because the fronts are less obvious.''
    371 
    372 '''''EXP22''': '''Oscillation''' '''__Barotropic__''' period 60s amplitude 16cm''
    373 
    374 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    375 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    376 ||''PCO/FALCON/Lumenera''||''before carriage''||''50ms''||''0.3''||''?''||''?''||''''''''''||
    377 
    378 '''''EXP23''': '''Oscillation''' '''__Barotropic__''' period 60s amplitude 46cm''
    379 
    380 ||'''''Cameras'''''||'''''location'''''||'''''exposure'''''||'''''dt'''''||'''''size'''''||'''''avg scale'''''||''''''''''||
    381 ||''''''''''||'||''$(ms)$''||''$(s)$''||''$pix.pix$''||''$pix/cm$''||''''''''''||
    382 ||''PCO/FALCON/Lumenera''||''before carriage''||''50ms''||''0.3''||''?''||''?''||''''''''''||
    383 
    384 ''The recycling of the water is started at the end of the day.''
    385 
    386 [[BR]]'''''Wednesday, March 1st 2017'''''
    387 
    388 ''Injector, reduction of its surface''
    389 
    390 '''''EXP23''': '''Inejctor''' '''diaphragm 19mm "'''''
    391 
    392 '''''EXP24''': '''Inejctor''' '''diaphragm 15mm "'''''
    393 
    394 ''We test the relation between the flow rate $Q[L/min]$ and the diameter of the diaphragm $D[mm]$. The relation gives the following figure.^^''
    395 
    396 ''[[Image(http://img4.hostingpics.net/pics/450503Diaphragmflowrate.png)]]''
    397 
    398 ||''Lumenera[[BR]]Settings''||''mean_dt[[BR]](ms)''||''mean_dx[[BR]](pix/mm)''||''Area[[BR]](pix/pix)''||''exposure[[BR]](ms)''||''contrast''||''brightness''||''gain''||
    399 ||''EXP24''||''320''||''1.44''||''4000x1800''||''220''||''3.26''||''39''||''3.64''||
    400 ||''EXP25''||''320''||''1.44''||''4000x1800''||''220''||''3.26''||''39''||''1.8-10[[BR]]''||
    401 
    402 '''''''''''
    403 
    404 '''''Thursday, 2 of March  2017'''''
    405 
    406 ||''Lumenera[[BR]]Settings''||''mean_dt[[BR]](ms)''||''mean_dx[[BR]](pix/mm)''||''Area[[BR]](pix/pix)''||''exposure[[BR]](ms)''||''contrast''||''brightness''||''gain''||
    407 ||''EXP27''||''322''||''1.1''||''4000x1800''||''220''||''3.26''||''39''||''1-8''||
    408 ||''EXP28''||''322''||''1.1''||''4000x1800''||''220''||''3.26''||''39''||''1-8[[BR]]''||
    409 
    410 ''Dist from surface =>1=>Hcoast=18cm Laser_surf=3.4cm; -1=>LAser_surf=3.2cm, 0=>Hcoast=18cm LAser_surf=5.2cm''
    411 
    412 ||''Position''||''M2''||''M1''||''M0''||''M-1''||''M-2''||
    413 ||''H_coast (cm)''||''''''''''||''18??''||''18''||''18''||
    414 ||''H_laser_up (cm)''||''''''''''||''14.6''||''12.8''||''14.8''||'||
    415 ||''H_laser_down (cm)''||''''''''''||'||''''''''''||'||''''''''''||
    416 
    417 ''Samuel starts the day by calibrating ultrasound probes. He also changed on probe (Acq 3. Third from the wall). Values are stored in the file : calib probe 02/03. He different positions are : 0/-0.5/-1/+1/+0.5/0''
    418 
    419 ''Profile made this morning is presented in the following figure. [[Image(http://img11.hostingpics.net/pics/601827Profilesweek3.png)]]''
    420 
    421 ''EXP27=> change of the laser position at 09.39.''
    422 
    423 '''''Friday, 3 of March 2017'''''
    424 
    425 ||''Lumenera[[BR]]Settings''||''mean_dt[[BR]](ms)''||''mean_dx[[BR]](pix/mm)''||''Area[[BR]](pix/pix)''||''exposure[[BR]](ms)''||''contrast''||''brightness''||''gain''||
    426 ||''EXP29''||''320''||''1.18''||''4000x1800''||''220''||''3.26''||''39''||''1-8''||
    427 ||''EXP30''||''320''||''1.18''||''4000x1800''||''220''||''3.26''||''39''||''1-8[[BR]]''||
    428 
    429 ''We lifted the ultrasound sensors of 42mm.''
    430 
    431 ''EXP29 =>10h19 13 D (FPS 3)''
    432 
    433 ''Mooving of the sensor closer to the wall''
    434 
    435 ''EXP30 =>11h46 16 D (FPS 10)''
    436 
    437 ''EXP31 =>14h42 19 D (FPS 10)''
    438 
    439 ''EXP32 =>16h08 15 D (FPS 10)''
    440 
    441 '''''Wednesday, 8 of March 2017'''''
    442 
    443 ||''Position''||''M2''||''M1''||''M0''||''M-1''||''M-2''||
    444 ||''H_coast (cm)''||''''''''''||'||''19''||''18''||
    445 ||''H_laser_up (cm)''||''''''''''||'||''15''||''14.3''||''''''''''||
    446 ||''H_laser_down (cm)''||''''''''''||'||''''''''''||'||''''''''''||
    447 
    448 ''EXP33 =>14h55 10.5 D (FPS 3) Problems with the camera PCO at the beginning. We need to compare the date of the first record with the trigger to obtain its time of start (~15h08).''
    449 
    450 ''Changement de vanne suite à une fuite.''
    451 
    452 ''EXP34  =>16h26 15 D (FPS 3) Problems with the camera FALCON at the  beginning. Delay of 201 frames with Dalsa2''
    453 
    454 ''EXP35  =>17h56 19 D (FPS 3) Problems with the camera FALCON at the  beginning. Several start of the trigger recorded are not representative of the start of the camera.''
    455 
    456 ||''Lumenera[[BR]]Settings''||''mean_dt[[BR]](ms)''||''mean_dx[[BR]](pix/mm)''||''Area[[BR]](pix/pix)''||''exposure[[BR]](ms)''||''contrast''||''brightness''||''gain''||
    457 ||''EXP29''||''320''||''1.18''||''4000x1800''||''220''||''3.26''||''39''||''1-8''||
    458 ||''EXP30''||''320''||''1.18''||''4000x1800''||''220''||''3.26''||''39''||''1-8[[BR]]''||
    459 
    460 '''''Thursday, 9 of March 2017'''''
    461 
    462 ||''Position''||''M2''||''M1''||''M0''||''M-1''||''M-2''||
    463 ||''H_coast (cm)''||''''''''''||''19.5''||''19.7''||''18.2''||
    464 ||''H_laser_up (cm)''||''''''''''||''17''||''16''||''15.5''||'||
    465 ||''H_laser_down (cm)''||''''''''''||'||''''''''''||'||''''''''''||
    466 
    467 ''Lumenera Settings''
    468 
    469 ||''mean_dt[[BR]](ms)''||''mean_dx[[BR]](pix/mm)''||''Area[[BR]](pix/pix)''||''exposure[[BR]](ms)''||''contrast''||''brightness''||''gain''||
    470 ||''EXP36''||''322''||''1.15''||''4000x1800''||''150''||''3.26''||''39''||''1-8''||
    471 ||''EXP37''||''310''||''1.2''||''4000x1800''||''200''||''1.7''||''37''||''2-9''||
    472 ||''EXP38''||''310''||''1.2''||''4000x1800''||''200''||''1.7''||''37''||''10-12''||
    473 
    474 [[BR]]''EXP36 =>[11h09:The 11h09]:50  The laser sheet before the wall pass through a clean (light) fluid layer without particles. This new option provides a significant increase of the intensity of illuminated particles in the experimental area !! Good option to keep for the next experiments.''
    475 
    476 ''Diaphragm 9mm / flow rate 24 lit/min''
    477 
    478 ''EXP37 => 14h12:30''
    479 
    480 ''Diaphragm 11.5mm / flow rate 33 lit/min (?? strange value according to the previous fit)''
    481 
    482 ''The position of lumen era camera was changed for this experiment and new calibration done.''
    483 
    484 ''Very nice upstream current with a well defined unstable wavelength on the steep slope.''
    485 
    486 ''EXP38 => 15h58''
    487 
    488 ''Diaphragm 13mm / flow rate 55 lit/min''
    489 
    490 ''Very nice upstream current with a well defined unstable wavelength on the steep slope. We test in the middle of the acquisition the laser sheet in the lower layer (-13cm). It confirms that the velocity in the lower layer is very weak.''
    491 
    492 '''''Friday, 10 of March 2017'''''
    493 
    494 ||''Position''||''M2''||''M1''||''M0''||''M-1''||''M-2''||
    495 ||''H_coast (cm)''||''''''''''||''20''||''20''||''19''||
    496 ||''H_laser_up (cm)''||''''''''''||''19''||''17''||''16''||'||
    497 ||''H_laser_down (cm)''||''''''''''||'||''''''''''||'||''''''''''||
    498 
    499 ''Lumenera Settings''
    500 
    501 ||''''''''''||''mean_dt[[BR]](ms)''||''mean_dx[[BR]](pix/mm)''||''Area[[BR]](pix/pix)''||''exposure[[BR]](ms)''||''contrast''||''brightness''||
    502 ||''EXP39''||''310''||''1.2''||''4000x1800''||''200''||''1.7''||''37''||''1-8''||
    503 ||''EXP40''||''310''||''1.2''||''4000x1800''||''200''||''1.7''||''37''||''17''||
    504 ||''EXP40[[BR]]video2''||''311''||''1.2''||''4000x1800''||''100''||''1.7''||''37''||''14''||
    505 ||''EXP41''||''311''||''1.2''||''4000x1800''||''100''||''1.7''||''37''||''17''||
    506 ||''EXP42''||''311''||''1.2''||''4000x1800''||''100''||''1.7''||''37''||''17-20''||
    507 ||''EXP43''||''311''||''1.2''||''4000x1800''||''100''||''1.7''||''37''||''13-16''||
    508 ||''EXP43_2''||''176''||''1.2''||''4000x1800''||''50''||''2.8''||''46''||''23''||
    509 
    510 [[BR]]''We start today with a frontal density current (like a buoyant river plume). In other words the injection of fresh water in a deepd fluid  layer of uniform density.''
    511 
    512 ''EXP39 start injection around =>09h20''
    513 
    514 ''Diaphragm 9mm / flow rate 24 lit/min''
    515 
    516 ''fps of PCO, DALSA, FALCON stays at 3 images/s''
    517 
    518 ''A very thin (small width) current flow along the wall, no apparent signature of instability or any meander formation . But due to the curvature of the laser sheet we didn't see what happens at the same depth everywhere... we are quite deep at the center (M0) of the wall while much closer to the surface at (M1 and M-1).''
    519 
    520 ''EXP40 =>10h06''
    521 
    522 ''Diaphragm 13mm / flow rate 54 lit/min''
    523 
    524 ''Always a stable density front with almost no impact of the bottom shelf bathymetry...''
    525 
    526 ''We forget to take a density profile inside the current ! grrr...''
    527 
    528 ''EXP41 =>10h!37:55''
    529 
    530 ''fps of PCO, DALSA, FALCON was changed to 10 images/s and for all the records below''
    531 
    532 ''Diaphragm 15mm / flow rate  75lit/min''
    533 
    534 ''Always a stable density front with a slight change on the width of the current from steep to gentle slope, but not sure that it is note due to the curvature of the laser sheet ...''
    535 
    536 ''EXP42 =>11h!05:55''
    537 
    538 ''Diaphragm 17mm / flow rate 88 lit/min''
    539 
    540 ''Always a stable density front with a slight change on the width of the current from steep to gentle slope, but not sure that it is note due to the curvature of the laser sheet ...''
    541 
    542 ''Several density profiles were done inside the coastal front.''
    543 
    544 ''EXP43 =>14h!32:30''
    545 
    546 ''Diaphragm 19mm / flow rate  120 lit/min''
    547 
    548 ''A roughly stable front with some few meanders or stretched eddies at the edge of the front.''
    549 
    550 '''''Wednesday, 15 of March 2017'''''
    551 
    552 ||''Position''||''M2''||''M1''||''M0''||''M-1''||''M-2''||
    553 ||''H_coast (cm)''||''''''''''||''6.6''||''6.9''||''7''||
    554 ||''H_laser_up (cm)''||''''''''''||''4.6''||''2.1''||''4''||'||
    555 ||''H_laser_down (cm)''||''''''''''||'||''''''''''||'||''''''''''||
    556 
    557 ''Lumenera Settings''
    558 
    559 ||''''''''''||''mean_dt[[BR]](ms)''||''mean_dx[[BR]](pix/mm)''||''Area[[BR]](pix/pix)''||''exposure[[BR]](ms)''||''contrast''||''brightness''||
    560 ||''EXP44''||''''''''''||''1.2''||''4000x1800''||''150''||''2.8''||''46''||''6-10''||
    561 ||''EXP45''||''''''''''||''1.2''||''4000x1800''||'||''''''''''||'||''17''||
    562 ||''EXP46[[BR]]''||''''''''''||''1.2''||''4000x1800''||'||''''''''''||'||''14''||
    563 ||''EXP47''||''''''''''||''1.2''||''4000x1800''||''200''||''2.8''||''46''||''14''||
    564 
    565 ''EXP44 =>08h48 fin 9h28''
    566 
    567 ''Diaphragm 9mm / flow rate 24 lit/min''
    568 
    569 ''A clear stagnation point occurs along the coast where the bathymetric slope changes. The impact of the bottom bathymetry is significantly stronger now.''
    570 
    571 ''On the other hand with the 40s period of rotation there is more vibration of the platform which may affect the stability of the recording cameras.''
    572 
    573 ''EXP45 =>10h10 fin ?''
    574 
    575 ''Diaphragm 13mm / flow rate 48 lit/min''
    576 
    577 ''The coastal current (and the eddies) pass over the bathymetric change without any stagnation points''
    578 
    579 ''EXP46 => 11h49 end 12h26''
    580 
    581 ''Diaphragm 10.5mm / flow rate 34.5 lit/min''
    582 
    583 ''Here again a stagnation point appears at the change of the bathymetric slope and the coastal flow is strongly reduced along the wall on the gentles slope area.''
    584 
    585 ''EXP47 =>14h11  end 15h00''
    586 
    587 ''Diaphragm 7.5mm / flow''