Changes between Version 36 and Version 37 of WikiStart

Timestamp:

Sep 13, 2017, 11:28:44 AM (7 years ago)

Author:

steiger5na

Comment:

--

WikiStart

@@ -170 +170 @@
 =  =
 = 7 - Diary: =
-'''Thursday 07 September'''
-
+== '''7.1 Thursday 07 September''' ==
 The cameras still have to be adjusted. After that is done, we take photos with the calibration grid in the horizontal and in 3D with both cameras that are fixed on the roof. With PIV, we conduct the calibration of both cameras as described in 4.1.
 
-'''Friday 08 September'''
-
+== '''7.2 Friday 08 September''' ==
 To verify the calibration, we took photos with both cameras with one ruler to see if the calibrations of the cameras agree (which it does!). Then, we added a wall into the tank to prevent the water of the freshwater experiments to return to the source. The laser height was adjusted.
 
-'''Monday 11 September'''
-
+== 7.3 Monday 11 September ==
 The 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.
 
@@ -222 +219 @@
 When turning to the horizontal cameras it was decided that sloping topography gave too many uncontrolled reflections that made it unsafe to increase the intensity. To remove these,parts of the bathymetry has to be Paint in black. The tank was set to empty during the night, while recycling the water.
 
-'''12 September'''
-
+== '''7.4 Tuesday 12 September''' ==
 The 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.
 
@@ -246 +242 @@
 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! '''
 
-'''13 September'''
-
+== '''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.
 
@@ -256 +251 @@
 '''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 waited for 5 more minutes until the flow is more established until we start the scan. 
+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 waited for 5 more minutes until the flow is more established until we start the scan.
 
 Note: During the scan, the laser is shaking too much! This needs to be changed.
 
-Observations: The bubble at the source disappeared due to the lower flow rate. The current follows along the slope and turns left at the 2nd curvature into the trough. After the 15 min after the flow was turned on, the flow bifurcates at the continental coast and at the trough and fills up the trough. The return flow does not follow along the upstream slope of the trough, but occurs in the middle of the trough. The main current along the slope is getting wider with time. [[BR]]''''''
+Observations: The bubble at the source disappeared due to the lower flow rate. The current follows along the slope and turns left at the 2nd curvature into the trough. After the 15 min after the flow was turned on, the flow bifurcates at the continental coast and at the trough and fills up the trough. The return flow does not follow along the upstream slope of the trough, but occurs in the middle of the trough. The main current along the slope is getting wider with time. [[BR]]''''''''''