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OPERATION MANUAL
Visualization Wind Tunnel “EdWin”
SrNo. VWT-V10.1
Contents
1. DESCRIPTION OF THE TUNNEL .................................................................................. 1
2. BASIC SETUP ..................................................................................................................... 4
3. OPERATION FOR FLOW VISUALIZATION (PANEL CONTROL MODE) .............. 8
4. OPERATION FOR POLAR MEASUREMENT (PC CONTROL MODE) ................. 10
5. APPENDIX ....................................................................................................................... 18
SMART BLADE® GmbH
Zuppingerstraße 14
88213 Ravensburg
GERMANY
Tel. +49-7511-977144-45
Fax. +49-7511-977144-50
Mail info@smart-blade.com
Client:
IITR - Indian Institute of Technology Ropar
Dr. Lipika Kabiraj
Department of Mechanical Engineering
Nangal Road
140001 Rupnagar, Punjab
INDIA
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Revisions
Rev.
R00
Date
21.05.2019
Author
JF
Changes
Initial release
List of Figures
Figure 1: Wind tunnel front view ...................................................................................................................................... 2
Figure 2: Wind tunnel rear view ........................................................................................................................................ 3
Figure 3: Open drawer at the bottom of the tunnel ................................................................................................... 4
Figure 4: Swimming switch of the vaporizer must flow at the top of the metal pin .................................... 4
Figure 5: The cylindrical perforated plate avoids water drops to fly beyond the basin ............................. 4
Figure 6: Pull out basin to dump water........................................................................................................................... 4
Figure 7: The LED modules can be dismounted as they are attached through neodymium magnets. . 5
Figure 8: When attaching the LED modules, it should be taken care of a good alignment of the
module with the section flanges (picture above is bad alignment) and of the LED lens with the slot
in the test section. .................................................................................................................................................................... 5
Figure 9: Right cabinet wall, connectors ........................................................................................................................ 6
Figure 10: Opening the window of the test section. .................................................................................................. 7
Figure 11: Tighten the 5.5mm nut for fixing the shaft of the wing with 1 to 2Nm torque; ensure
levelness by a custom spirit level gage. ........................................................................................................................... 7
Figure 12: Control Cabinet (left side, manual control elements) ......................................................................... 8
Figure 13: 3-COMPONENT-BALANCE installed at the rear of the test section ............................................ 10
Figure 14: Ambien data sensor box ............................................................................................................................... 11
Figure 15: Tablet PC installed at the bracket on the right cabinet door ......................................................... 11
Figure 16: HIGH SPEED INSERTS installed in the test section ........................................................................... 12
Figure 17: Start screen of the VWT Control software ............................................................................................ 13
Figure 18: "Settings" tab of the software..................................................................................................................... 14
Figure 19: Keypad for manually entering values ..................................................................................................... 15
Figure 20: "Manual Control" tab of the software ..................................................................................................... 16
Figure 21: "Polar Measure" tab of the software........................................................................................................ 17
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Figure 22: To open the access hatch, loosen the red screws and move the hatch until it can be
pushed inside the duct ........................................................................................................................................................ 18
Figure 23: Rotate and pull the hatch out of the duct .............................................................................................. 18
Figure 24: Original airfoil test bodies and custom spirit level gages; NACA0012-64, FX63137 .......... 19
Figure 27: System Information tab ................................................................................................................................ 21
Figure 25: Screen after hitting “Exit” button. To restart the software, click the "Run" icon at the
upper left. For closing the application, hit “X” at the upper right. .................................................................... 22
Figure 26: Windows Desktop with WiFi connected (right) and software executable file to restart the
software manually ................................................................................................................................................................ 22
Figure 28: Exemplary data plots of NACA0012 airfoil, measured at 100% fan speed with High Speed
Insert (~14.4m/s), 1s wait time, 4s measurement time, -15° to +15°AoA, 30steps, Reverse Move, 1
Repeat Cycle ............................................................................................................................................................................ 23
List of Tables
Table 1: Original airfoil profile data .............................................................................................................................. 19
Table 2: Exemplary content of *.csv file for cL(AoA) and cD(AoA)................................................................... 24
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1. Description of the Tunnel
The SMART BLADE Visualization Wind Tunnel “EdWin” is a mobile, closed-loop type wind tunnel. The
product was designed for making aerodynamics more of an experience than theory for students by
visualizing complex airflow around various shapes with water vapor and light.
The main components are the following (see also Figure 1 and Figure 2):
•
Variable speed axial fan
•
Ultrasonic humidifier and water reservoir
•
Flow straightener and turbulence screen
•
Contraction section / nozzle with pressure ring lines
•
Heat grid assembly
•
Closed test section with:
o
Removable window made of safety glass with anti-reflection coating
o
Two LED modules for light sheet generation in test section (top and bottom)
o
3-component balance for lift, drag and momentum measurement, including servo
motor for electronic variation of angle of attack (attachment of wings or test bodies by
expansion shaft in 6mm hollow shaft of the balance)
o
Test airfoils (NACA0012 and FX63137 with 200mm span and 140mm chord)
•
Debris catch mesh downstream of the test section
•
Throttle flap (made of perforated plate) for manual flow regulation
•
Control cabinet with:
•
o
Control panel for manual regulation of: fan speed, heating, light and angle of attack, as
well as switches for: fog, input control and preset recall
o
11” Windows® Tablet, including preinstalled custom software “VWT Control”
o
USB-B type female connector for link to external control PC
Frame, including four steering rollers (two with brakes)
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Figure 1: Wind tunnel front view
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Figure 2: Wind tunnel rear view
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2. Basic setup
Plug in the tunnel to a ~220 V AC power wall outlet, fused for 15 Ampere.
2.1. Flow visualization – fill water
1. Open the water reservoir drawer at the bottom of the tunnel by pulling the silver handle (Figure 3).
2. Add distilled water into the tray until the ultrasonic vaporiser is floating with it’s buoyant ring and
the little white swimming switch is also fully lifted to the top of the metal pin, as in Figure 4. (First
time fill capacity: around 10 liters)
3. Close the tray again.
Figure 3: Open drawer at the bottom of
the tunnel
Figure 4: Swimming switch of the vaporizer must
flow at the top of the metal pin
Figure 5: The cylindrical perforated
plate avoids water drops to fly beyond
the basin
Figure 6: Pull out basin to dump water
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2.2. Flow visualization – install LED modules
Install both LED modules and check their proper alignment with the slots in the test section (Figure 7).
The modules are electrically connected to the right of the cabinet (Figure 9).
Take care, not to look into the LED lens directly when the module is turned on, as it is very bright!
Figure 7: The LED modules can be dismounted as they are attached
through neodymium magnets.
Figure 8: When attaching the LED modules, it should be taken care of a
good alignment of the module with the section flanges (picture above is
bad alignment) and of the LED lens with the slot in the test section.
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Figure 9: Right cabinet wall, connectors
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2.3. Installation of test object
1. Opening the window of the test section: Lift it about 10 mm so that it comes free at its lower edge.
Then pull the lower edge about 20 mm away from the test section and lower it until it comes also
free at its upper edge. (Figure 10)
2. Ensure that the AOA is set to 0° (potentiometer or software)
3. Mount a test wing by carefully pushing its shaft into the hole at the rear wall of the test section
(into brass part of the 3-component-balance).
4. Use the custom spirit level gage to adjust the wing to a horizontal position.
5. Use a torque wrench and a 5.5mm hex wrench socket and tighten the nut on the wing shaft with
min. 1 Nm to max. 2 Nm torque (Figure 11). If the nut cannot be tensioned, take it out again and
ensure that the conical brass nut at the tip of the wing shaft is just so slightly touching the shaft
conical bore, that it will be held by friction.
6. The angular 0° position can be fine adjusted after tensioning by carefully rotating the tensioned
wing and checking with the spirit level gage.
7. For polar measurements, the window needs to be closed again.
Hint: You can also use custom test objects (e.g. cylinders of different diameter), attached by magnets to
the back wall of the test section.
Figure 10: Opening the window of
the test section.
Figure 11: Tighten the 5.5mm nut for fixing the shaft of
the wing with 1 to 2Nm torque; ensure levelness by a
custom spirit level gage.
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3. Operation for Flow Visualization (panel control mode)
For the purpose of flow visualization, it is best practice to use the manual control panel at the cabinet
(Figure 12) to finely adjust the settings. Before starting, perform all steps of the basic setup as
described in chapter 2.
•
Use the MAIN SWITCH at the control panel to turn the wind tunnel on.
•
Ensure, the switches for PC CONTROL and PRESET are turned to OFF position.
•
Adjust the fan speed with the SPEED potentiometer (value of 0.5 to 2 recommended for flow vis).
•
Turn on the light sheet with the LED potentiometer (value of 5 to 10 for flow vis).
•
Turn on the FOG switch. (It takes a few minutes for the vaporizer to generate sufficient fog for flow
vis. Turn down the fan speed to allow for quicker development of dense fog).
•
Adjust the HEATING potentiometer (value between 5 to 10 for flow vis).
•
For more laminar flow, the throttle valve should be in a rather closed position (¾ to full closed).
•
The angle of attack of the test airfoil is set by the AOA potentiometer.
Figure 12: Control Cabinet (left side, manual control elements)
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3.1. Using a set of PRESET values
The PRESET ON/OFF switch overrides the switches and potentiometers with a set of values, stored
before by using the SAVE button. It sets the fan, fog, heating and LEDs to previously saved values.
Use the preset mode e.g. to store settings that result in a good visualization and quickly recall them.
To save a set of settings, set the PRESET switch to OFF, adjust your desired settings via the manual
control elements and then push the SAVE button. You can then at any point later on switch PRESET to
ON and the tunnel adopts the stored settings (when the tunnel is switched off they will be stored as
well). The settings can be changed frequently (e.g. to prepare for ambient conditions, prior to a
lecture).
3.2. Further notes on Flow Visualization
The optimal settings of HEAT, SPEED and throttle valve depend on ambient conditions (temperature,
humidity, atmospheric pressure) and have to be tuned in for changing environments.
With closed window, the visualization is more stable and the conditions may sooner come to
equilibrium.
After some minutes of operation with vapor and closed window, water might condensate on the
inner side of the window. To avoid this, the best method is to apply anti-fog spray which is included in
the shipment and is applied in the delivery condition.
Application of anti-fog spray:
1. Take out the window and put it on a table with the “inside wall” facing up.
2. Spray on several pump strokes evenly
3. Quickly distribute the liquid with a small piece of tissue to wet out the whole surface evenly. Do not
rub or wipe dry, but maintain a wetted surface!
4. Allow it to dry for a few minutes before putting back the window into the tunnel.
Note: The spray gives the window a smeary look. The window should not be cleaned though! (only
when new spray is intended to be applied).
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4. Operation for polar measurement (PC Control mode)
This section describes the use of the wind tunnel functions by software (either by delivered tablet PC
or external PC, connected via USB wire). This allows for the measurement of wind speed,
environmental data and aerodynamic forces by the AMBIENT DATA SENSOR BOX and the 3COMPONENT-BALANCE.
The main purpose of the software is to conduct automated 2D airfoil polar measurements, as a
common task in wind tunnel operation. A recent feature is the short time logging of the full set of
acquired sensor values for various other studies.
4.1. Hardware Setup & Connection
4.1.1 3-Component-Balance
The 3-COMPONENT-BALANCE (Figure 13) is attached to the rear of the test section by strong magnets.
Mount it by slightly tilting it from the vertical position, aligning the top bracket with the tunnel top
edge, centering the bracket and carefully rotating the balance to vertical until the magnets pull it into
place. Ensure from the front side of the test section, that the brass hub is centered to the hole in the
back wall. Connect all the cables for FZ, FX, MY and SERVO to the M8 sockets at the right of the cabinet
and secure the screw-type locking (Figure 9).
Figure 13: 3-COMPONENT-BALANCE installed at the rear of the test section
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4.1.2 Ambient Data Sensor Box
The AMBIENT DATA SENSOR BOX (Figure 14) is attached to the back of the test section by magnets. It
comprises the differential pressure sensor for measuring wind speed, which is connected to the nozzle
pressure ring lines by clear PVC tubes. A grey pin shaped sensor for measuring humidity and
temperature of the flow is mounted in the corner piece behind the test section and is connected to the
box by a cable. The Ambient Data Sensor Box is connected to the main cabinet M8 socket “Speed
Module” at the right side of the cabinet (Figure 9).
Take care to screw in the plugs securely, to establish safe contact!
Figure 14: Ambien data sensor box
4.1.3 Windows Tablet PC
The user interface is realized on a 11” WINDOWS TABLET PC which is installed at the right front side
of the cabinet on a custom bracket (Figure 15). Inside the bracket is a USB-A socket for permanently
connecting the tablet to a power source via micro USB.
Figure 15: Tablet PC installed at the bracket on the right cabinet door
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4.1.4 High Speed Inserts
For maximizing the Reynolds number, the maximum achievable wind speed of the tunnel can be
increased by installing the HIGH SPEED INSERTS in the test section. They narrow down the test section
cross section to accelerate the flow. The High Speed Inserts consist of 2x three 3D printed parts,
attached by magnets to the ceiling and floor of the test section (see Figure 16). Take care to align them
properly with the test section inlet flange and among each other. They do not reach past the Heatgrid
wires at the test section inlet!
Note that for correct wind speed measurement, the presence of High Speed Inserts must be toggled in
the Software Settings!
Figure 16: HIGH SPEED INSERTS installed in the test section
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4.2. Software Startup & Connection
Turn on the wind tunnel with the MAIN SWITCH.
Ensure that the PRESET switch is in OFF position and PC CONTROL is switched to ON.
Turn on the tablet PC and log in with the “IITR” account.
After bootup & login, the tablet PC will automatically connect to the WiFi hotspot of the NI myRIO,
which is installed in the tunnel’s cabinet. (the SSID is “VWT”)
As well, the Software will start automatically, as the *.exe file is set up to run in the Windows Autostart
procedure. The executable file is also placed on the Windows Desktop.
You will be requested to choose a connection mode in the initial screen of the software (Figure 17). The
prior choice here is WiFi.
Figure 17: Start screen of the VWT Control software
When the software is started and correctly connected to the WiFi, the Settings tab appears, as in Figure
18: The status lights in the lower left frame will be green and the IP Address is displayed.
If the manual control switch PC CONTROL at the cabinet is set to OFF, the status light in the “PC
Control” frame is greyed out. The PC CONTROL switch can be set on and off, while the software is
running, and the status is reflected by the software status light. The manual control elements (Speed,
LED, Heat, Fog) at the cabinet are disabled and enabled vice-versa.
If any of the mentioned functionality so far is not given, please refer to section 5.4.1 Troubleshooting.
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4.2.1 “Settings” software tab
Figure 18: "Settings" tab of the software
The Settings tab allows to adjust various initial settings and values (Figure 18 from left to right):
•
Velocity
The actual measured wind speed in the test section is displayed in [m/s]. For accurate velocity
measurements it is necessary to initially correct the differential pressure sensor for offset (zeroing
it) at no wind speed (with the fan turned off). This is done by hitting the “Take Velocity Offset”
button.
•
Differential Pressure
The differential pressure raw value which is measured between the wind tunnel nozzle inlet and
outlet sections is displayed (corrected for offset).
•
Ambient Data
Those set of values are used for calculating the wind speed, as well as lift, drag & momentum
coefficients.
The values for ambient temperature, absolute pressure and relative humidity are directly
measured. The values for Air density and Kinematic viscosity are calculated from those. If fix values
might be desired (e.g. external equipment is used to measure & calculate wind speed), these values
can be entered in the respective fields when prior changing to “Enter Values Manual” in the
respective “Sensor Mode” frame.
•
PC Control
Enabling/disabling and setting values for the basic wind tunnel functions Fan, Light & Heat.
•
Sensor Mode
If externally measured data for Ambient Data shall be used, it can be selected here (see also
Ambient Data description).
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•
Speed Mode
If the test section is equipped with the High Speed Inserts (Figure 16), it must be selected here.
The software uses different pressure calibration factors for calculating the correct wind speed at
the position of the airfoil.
•
Velocity Measurement
The default speed measurement method for the present IITR wind tunnel is via the differential
pressure at the inlet nozzle. A Prandtl tube would require different calibration factors and is
additional accessory.
•
Data Logging and Display
Setting the sample rate for display and data logging functionality in the Manual Control tab.
•
Airfoil
Entering chord & span values for correctly calculating lift, drag & momentum coefficients, as well
as the Reynolds Number
•
Motor Data – Gear Ratio
The airfoil angle of attack is controlled by a servo motor with belt transmission, both installed at
the 3-Component-Balance. The transmission gear ratio with the present tunnel configuration is
30:60 and doesn’t need to be changed. Max & min achievable AoA are given.
•
Preset Values
Saving & loading Preset Values for the basic Fan, Light, Heat & Fog settings, as described earlier in
section 3.1.
•
LED Strobe
For experimenting with visualization of periodic flow phenomena, the LED lights can be flashed.
How to enter values manually:
1. click/tap in an editable number field
2. a keypad is appearing in the screen center
3. enter the desired value
4. hit ENTER
Figure 19: Keypad for manually
entering values
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4.2.2 “Manual Control” software tab
In the Manual Control tab, following funcions are available:
•
Load Cell
The Get Forces Offset button is offsetting the readings from the load cells of the 3-componentbalance by the current values, to compensate for the mass of a test object. It should be used prior
to starting the fan of the wind tunnel.
•
Control AoA
The servo motor can be controled to set a test object / airfoil to certain angle of attack by either
adjusting a slider or entering values manually. After entering values manually, the Move AoA button
has to be pushed for confirmation.
•
Logging
For experiments where time-resolved measurements of the sensor data are required, a basic
logging function is implemented. It saves all the sensor data the system is processing in a text file.
The data logging frequency can be set in the Settings tab. After logging is stopped, the file path can
be selected. Exemplary data is shown in Appendix 5.4.3 .
•
Two waveform charts display the dimensionless coefficients cL,cD & cM and the measured forces
FL (lift or FZ) and FD(drag or FX) as well as the torque M (pitching moment or MY).
Figure 20: "Manual Control" tab of the software
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4.2.3 “Polar Measurement” software tab
This part of the software enables you to configure & conduct fully automated airfoil polar
measurement routines.
•
Polar Measurement
For the AoA range to be examined by the routine, a AoA Start and Stop angle as well as a number of
intersecting Steps can be defined. Keep in mind that the min and max values are limited by the
servo range, which is displayed in the Settings tab. With regards to the capabilities of the servo
motor, a single movement should not be smaller than 0.5°, while 1° increments are recommended.
When Single Move is selected, the measurement routine will be performed only in one direction.
When Reverse Move is selected, the routine will be performed in a forward and reverse cycle.
Additional Repeat Cycles can be defined and the routine will be performed as many times again, as
entered.
•
Timing
Setting the measurement & wait times for the polar measurement routine. The wait time is a dead
time where no data is acquired after the AoA (servo) has moved. Thereby dynamic effects can be
excluded from the measurements (aerodynamic or structural vibrations). The measurement time
is the time for which data is acquired and averaged at each AoA step.
When all values are chosen, the offset compensation Get Forces Offset in the Settings tab should be
performed at no wind speed. After the wind speed is set and the tunnel stabilized at the desired speed,
the Start button can be hit and the measurement routine will start. Averaged and calculated airfoil
coefficients can be observed live in the diagrams parallel to the measurement. Above the diagrams, the
plot to display in the right window can be selected. After the measurement is finished, the plots and
measured data can be saved by clicking the Save Plots or Save Data buttons. The data will be saved on
the host PC (tablet or connected PC). Exemplary data is shown in Appendix 5.4.2 .
Figure 21: "Polar Measure" tab of the software
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5. Appendix
5.1. Preventive Maintenance
After each usage with fog, the tunnel should be dried by operating it for about 15 min at the highest
speed and without window.
For longer downtimes, say a few days, the tunnel section above the vaporizer reservoir (containing the
fan) should be dried with a sponge through both access holes (Figure 22, Figure 23). To make sure that
all the water contained in the wind tunnel is collected in the lower duct, the tunnel should be switched
on again after a drying with a sponge and then dried again (iterative process). It is also advised to
empty the water basin, when the tunnel is not used for an even longer period of time (dump the water,
as in Figure 6).
Do not operate the vaporizer when running at speeds higher than ~8m/s (potentiometer value of
around 7)! Otherwise water will be splashed into the tunnel.
Figure 22: To open the access hatch, loosen
the red screws and move the hatch until it
can be pushed inside the duct
Figure 23: Rotate and pull the hatch
out of the duct
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5.2. Original Airfoils
Following airfoils are delivered with the tunnel.
Table 1: Original airfoil profile data
NACA0012-64 FX63137
Chord
140mm
140mm
Span
197mm
197mm
Pitch axis, x
70mm
70mm
Pitch axis, y
0mm
8mm
TE thickness 0.6mm
0.6mm
The method of attachment is by a dia 6mm expansion shaft in a hollow shaft of the balance. A drawing
with the main functional dimensions of the wing attachment environment is delivered separately.
Figure 24: Original airfoil test bodies and custom spirit level gages; NACA0012-64, FX63137
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5.3. Sensors
Load Cells
FX, FZ: ASCELL - AM3kg
MY: ME-Systeme - TS70
Amplifiers: ME-Systeme - GSV6L
Prandtl probe, Differential pressure sensor
Probe manufactured with internal specs
AMSYS - AMS5915-0005-D
The system is calibrated for accurate measurements in an unblocked test section (no test object
installed) at x=200mm for wind speeds above 4m/s with an error <2%.
Absolute pressure sensor
Bosch Sensortec - BMP280
Temperature & Humidity sensor
Aosong - AM2315
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5.4. Software
This manual refers to Software Version “VWT-V10.1_IITR”.
5.4.1 Troubleshooting
•
The “System Information” section of the software allows for some basic analysis on the correct
performance of all modules. (connections, measured raw data, processor load). See Figure 25
•
If the application fails to work as intended (hanged up) and /or closing via the “Exit” button
doesn’t work, shut the software down by the Windows Task Manager (long-press on the
Windows Taskbar, select “Task Manager”, select the “EDWINHost” task and hit “End Task” at the
lower right)
To cleanly restart everything, firstly power-cycle the Wind Tunnel by the Main Switch, wait
until the Tablet has established the connection to the WiFi again (Figure 27) and then start the
Software manually from the Desktop.
•
Always perform “Take Velocity Offset” as the last step after changing other measurement
variables in the software (but before turning on the fan).
Figure 25: System Information tab
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Figure 26: Screen after hitting “Exit” button. To restart the software, click the "Run" icon at the
upper left. For closing the application, hit “X” at the upper right.
Figure 27: Windows Desktop with WiFi connected (right) and software executable file to restart
the software manually
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5.4.2 Exemplary Polar data
Figure 28: Exemplary data plots of NACA0012 airfoil, measured at 100% fan speed with High
Speed Insert (~14.4m/s), 1s wait time, 4s measurement time, -15° to +15°AoA, 30steps, Reverse
Move, 1 Repeat Cycle
Due to the simplicity of the system, a hysteresis of around 3 to 5deg is present and could not be further
avoided. This originates from:
• the tolerated error value in the servo controller electronics
• minimal gear backlash in the servo gears
• minimal elasticity of the toothed belt & in the teeth-to-gear-contact
The gear ratio of 30:60 is aimed at reducing this hysteresis, but reduces the effective AoA range from
+/-64° to +/-32°. To avoid falsified measurements when measuring a polar in the positive AoA
Doc. Name: EdWin- OperationManual
Doc. No. : VWT-10.1-102
Rev. No. : R00
Status: RELEASE
Date: 21.05.2019
Page: 24 / 27
direction (e.g. -15 to +15°), always fine-adjust the airfoil (as in section 2.3) by rotating it the last
degrees from the direction of positive AoA into the 0° leveled position.
Table 2: Exemplary content of *.csv file for Polar Plot data
AoA [°]
-15.00
-14.00
-13.00
-12.00
-11.00
-10.00
-9.00
-8.00
-7.00
-6.00
-5.00
-4.00
-3.00
-2.00
-1.00
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
11.00
12.00
13.00
14.00
15.00
14.00
13.00
12.00
11.00
10.00
9.00
8.00
7.00
6.00
5.00
4.00
3.00
2.00
1.00
0.00
-1.00
-2.00
-3.00
-4.00
-5.00
-6.00
-7.00
-8.00
-9.00
-10.00
-11.00
-12.00
-13.00
-14.00
-15.00
-15.00
-14.00
-13.00
-12.00
-11.00
-10.00
-9.00
-8.00
-7.00
-6.00
-5.00
cL [-]
-0.94
-0.93
-0.97
-0.90
-0.83
-0.82
-0.77
-0.72
-0.68
-0.61
-0.53
-0.47
-0.40
-0.31
-0.12
-0.03
-0.02
0.00
0.10
0.21
0.35
0.44
0.51
0.57
0.62
0.67
0.73
0.75
0.79
0.84
0.93
0.88
0.83
0.79
0.74
0.71
0.64
0.60
0.51
0.47
0.41
0.30
0.18
0.08
0.02
-0.01
-0.05
-0.14
-0.24
-0.37
-0.45
-0.50
-0.56
-0.63
-0.72
-0.78
-0.82
-0.83
-0.88
-0.93
-0.98
-0.97
-0.97
-0.94
-0.91
-0.83
-0.81
-0.79
-0.72
-0.68
-0.62
-0.53
AoA [°]
-15.00
-14.00
-13.00
-12.00
-11.00
-10.00
-9.00
-8.00
-7.00
-6.00
-5.00
-4.00
-3.00
-2.00
-1.00
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
11.00
12.00
13.00
14.00
15.00
14.00
13.00
12.00
11.00
10.00
9.00
8.00
7.00
6.00
5.00
4.00
3.00
2.00
1.00
0.00
-1.00
-2.00
-3.00
-4.00
-5.00
-6.00
-7.00
-8.00
-9.00
-10.00
-11.00
-12.00
-13.00
-14.00
-15.00
-15.00
-14.00
-13.00
-12.00
-11.00
-10.00
-9.00
-8.00
-7.00
-6.00
-5.00
cD [-]
0.26
0.25
0.26
0.23
0.16
0.13
0.11
0.10
0.09
0.08
0.07
0.07
0.06
0.06
0.05
0.05
0.05
0.05
0.05
0.06
0.06
0.07
0.07
0.08
0.09
0.09
0.10
0.11
0.13
0.19
0.26
0.21
0.18
0.12
0.11
0.10
0.09
0.08
0.07
0.07
0.06
0.06
0.05
0.05
0.05
0.05
0.05
0.05
0.05
0.06
0.06
0.07
0.07
0.08
0.09
0.11
0.12
0.15
0.21
0.25
0.29
0.28
0.27
0.26
0.23
0.16
0.13
0.11
0.09
0.09
0.08
0.07
AoA [°]
-15.00
-14.00
-13.00
-12.00
-11.00
-10.00
-9.00
-8.00
-7.00
-6.00
-5.00
-4.00
-3.00
-2.00
-1.00
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
11.00
12.00
13.00
14.00
15.00
14.00
13.00
12.00
11.00
10.00
9.00
8.00
7.00
6.00
5.00
4.00
3.00
2.00
1.00
0.00
-1.00
-2.00
-3.00
-4.00
-5.00
-6.00
-7.00
-8.00
-9.00
-10.00
-11.00
-12.00
-13.00
-14.00
-15.00
-15.00
-14.00
-13.00
-12.00
-11.00
-10.00
-9.00
-8.00
-7.00
-6.00
-5.00
cL/cD [-] cD [-]
-3.58
0.26
-3.66
0.25
-3.68
0.26
-3.95
0.23
-5.21
0.16
-6.35
0.13
-7.21
0.11
-7.56
0.10
-7.67
0.09
-7.65
0.08
-7.46
0.07
-7.16
0.07
-6.58
0.06
-5.35
0.06
-2.22
0.05
-0.66
0.05
-0.35
0.05
0.03
0.05
1.79
0.05
3.71
0.06
5.72
0.06
6.59
0.07
6.96
0.07
7.13
0.08
7.19
0.09
7.21
0.09
6.97
0.10
6.72
0.11
5.90
0.13
4.37
0.19
3.61
0.26
4.11
0.21
4.68
0.18
6.39
0.12
6.90
0.11
7.16
0.10
7.30
0.09
7.25
0.08
7.07
0.07
6.91
0.07
6.53
0.06
5.14
0.06
3.36
0.05
1.47
0.05
0.32
0.05
-0.10
0.05
-1.00
0.05
-2.74
0.05
-4.40
0.05
-6.44
0.06
-7.18
0.06
-7.47
0.07
-7.68
0.07
-7.74
0.08
-7.59
0.09
-7.19
0.11
-6.54
0.12
-5.68
0.15
-4.13
0.21
-3.78
0.25
-3.43
0.29
-3.42
0.28
-3.60
0.27
-3.69
0.26
-3.94
0.23
-5.27
0.16
-6.16
0.13
-6.93
0.11
-7.56
0.09
-7.63
0.09
-7.67
0.08
-7.43
0.07
cL [-]
-0.94
-0.93
-0.97
-0.90
-0.83
-0.82
-0.77
-0.72
-0.68
-0.61
-0.53
-0.47
-0.40
-0.31
-0.12
-0.03
-0.02
0.00
0.10
0.21
0.35
0.44
0.51
0.57
0.62
0.67
0.73
0.75
0.79
0.84
0.93
0.88
0.83
0.79
0.74
0.71
0.64
0.60
0.51
0.47
0.41
0.30
0.18
0.08
0.02
-0.01
-0.05
-0.14
-0.24
-0.37
-0.45
-0.50
-0.56
-0.63
-0.72
-0.78
-0.82
-0.83
-0.88
-0.93
-0.98
-0.97
-0.97
-0.94
-0.91
-0.83
-0.81
-0.79
-0.72
-0.68
-0.62
-0.53
AoA [°]
-15.00
-14.00
-13.00
-12.00
-11.00
-10.00
-9.00
-8.00
-7.00
-6.00
-5.00
-4.00
-3.00
-2.00
-1.00
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
11.00
12.00
13.00
14.00
15.00
14.00
13.00
12.00
11.00
10.00
9.00
8.00
7.00
6.00
5.00
4.00
3.00
2.00
1.00
0.00
-1.00
-2.00
-3.00
-4.00
-5.00
-6.00
-7.00
-8.00
-9.00
-10.00
-11.00
-12.00
-13.00
-14.00
-15.00
-15.00
-14.00
-13.00
-12.00
-11.00
-10.00
-9.00
-8.00
-7.00
-6.00
-5.00
cM [-]
-0.20
-0.20
-0.21
-0.20
-0.22
-0.23
-0.21
-0.19
-0.18
-0.16
-0.13
-0.11
-0.09
-0.06
-0.03
-0.01
-0.01
-0.00
0.02
0.04
0.07
0.10
0.12
0.14
0.15
0.17
0.19
0.20
0.21
0.20
0.19
0.20
0.20
0.21
0.19
0.18
0.16
0.15
0.12
0.11
0.09
0.05
0.03
0.01
0.00
-0.00
-0.02
-0.04
-0.05
-0.08
-0.10
-0.12
-0.14
-0.17
-0.19
-0.21
-0.23
-0.23
-0.21
-0.21
-0.20
-0.20
-0.21
-0.21
-0.21
-0.22
-0.22
-0.22
-0.19
-0.18
-0.16
-0.13
Doc. Name: EdWin- OperationManual
Doc. No. : VWT-10.1-102
Rev. No. : R00
-4.00
-3.00
-2.00
-1.00
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
11.00
12.00
13.00
14.00
15.00
14.00
13.00
12.00
11.00
10.00
9.00
8.00
7.00
6.00
5.00
4.00
3.00
2.00
1.00
0.00
-1.00
-2.00
-3.00
-4.00
-5.00
-6.00
-7.00
-8.00
-9.00
-10.00
-11.00
-12.00
-13.00
-14.00
-15.00
-0.45
-0.39
-0.31
-0.17
-0.03
-0.01
0.00
0.09
0.24
0.34
0.45
0.52
0.57
0.63
0.66
0.73
0.74
0.81
0.84
0.91
0.88
0.83
0.78
0.74
0.72
0.66
0.60
0.52
0.46
0.44
0.35
0.22
0.08
0.02
-0.01
-0.04
-0.18
-0.27
-0.35
-0.44
-0.49
-0.55
-0.64
-0.68
-0.77
-0.81
-0.83
-0.88
-0.94
-0.94
-4.00
-3.00
-2.00
-1.00
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
11.00
12.00
13.00
14.00
15.00
14.00
13.00
12.00
11.00
10.00
9.00
8.00
7.00
6.00
5.00
4.00
3.00
2.00
1.00
0.00
-1.00
-2.00
-3.00
-4.00
-5.00
-6.00
-7.00
-8.00
-9.00
-10.00
-11.00
-12.00
-13.00
-14.00
-15.00
0.06
0.06
0.06
0.05
0.05
0.05
0.05
0.05
0.06
0.06
0.07
0.07
0.08
0.09
0.09
0.10
0.11
0.15
0.19
0.25
0.22
0.18
0.12
0.11
0.10
0.09
0.08
0.07
0.07
0.07
0.06
0.06
0.05
0.05
0.05
0.05
0.05
0.06
0.06
0.06
0.07
0.07
0.08
0.09
0.11
0.13
0.15
0.20
0.26
0.26
-4.00
-3.00
-2.00
-1.00
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
11.00
12.00
13.00
14.00
15.00
14.00
13.00
12.00
11.00
10.00
9.00
8.00
7.00
6.00
5.00
4.00
3.00
2.00
1.00
0.00
-1.00
-2.00
-3.00
-4.00
-5.00
-6.00
-7.00
-8.00
-9.00
-10.00
-11.00
-12.00
-13.00
-14.00
-15.00
-7.08
-6.57
-5.30
-3.07
-0.49
-0.12
0.02
1.72
4.29
5.67
6.65
7.02
7.16
7.22
7.21
6.96
6.83
5.51
4.38
3.69
3.99
4.57
6.40
6.94
7.13
7.31
7.31
7.20
6.83
6.67
5.84
4.01
1.53
0.32
-0.10
-0.79
-3.27
-4.85
-6.08
-7.12
-7.41
-7.68
-7.75
-7.70
-7.18
-6.48
-5.66
-4.31
-3.66
-3.66
0.06
0.06
0.06
0.05
0.05
0.05
0.05
0.05
0.06
0.06
0.07
0.07
0.08
0.09
0.09
0.10
0.11
0.15
0.19
0.25
0.22
0.18
0.12
0.11
0.10
0.09
0.08
0.07
0.07
0.07
0.06
0.06
0.05
0.05
0.05
0.05
0.05
0.06
0.06
0.06
0.07
0.07
0.08
0.09
0.11
0.13
0.15
0.20
0.26
0.26
-0.45
-0.39
-0.31
-0.17
-0.03
-0.01
0.00
0.09
0.24
0.34
0.45
0.52
0.57
0.63
0.66
0.73
0.74
0.81
0.84
0.91
0.88
0.83
0.78
0.74
0.72
0.66
0.60
0.52
0.46
0.44
0.35
0.22
0.08
0.02
-0.01
-0.04
-0.18
-0.27
-0.35
-0.44
-0.49
-0.55
-0.64
-0.68
-0.77
-0.81
-0.83
-0.88
-0.94
-0.94
-4.00
-3.00
-2.00
-1.00
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
11.00
12.00
13.00
14.00
15.00
14.00
13.00
12.00
11.00
10.00
9.00
8.00
7.00
6.00
5.00
4.00
3.00
2.00
1.00
0.00
-1.00
-2.00
-3.00
-4.00
-5.00
-6.00
-7.00
-8.00
-9.00
-10.00
-11.00
-12.00
-13.00
-14.00
-15.00
-0.11
-0.08
-0.06
-0.04
-0.01
-0.01
-0.00
0.02
0.04
0.06
0.10
0.12
0.14
0.16
0.17
0.19
0.19
0.21
0.20
0.19
0.19
0.20
0.21
0.19
0.18
0.17
0.15
0.12
0.10
0.09
0.06
0.04
0.01
0.00
-0.00
-0.02
-0.04
-0.06
-0.07
-0.10
-0.12
-0.14
-0.17
-0.18
-0.21
-0.23
-0.23
-0.21
-0.20
-0.21
Status: RELEASE
Date: 21.05.2019
Page: 25 / 27
Doc. Name: EdWin- OperationManual
Doc. No. : VWT-10.1-102
Rev. No. : R00
Status: RELEASE
Date: 21.05.2019
Page: 26 / 27
5.4.3 Exemplary Real Time Data Log
Date_Time
2019_02_27_18_05
_12
2019_02_27_18_05
_12
2019_02_27_18_05
_12
2019_02_27_18_05
_12
2019_02_27_18_05
_13
2019_02_27_18_05
_13
2019_02_27_18_05
_13
2019_02_27_18_05
_13
2019_02_27_18_05
_13
2019_02_27_18_05
_13
2019_02_27_18_05
_13
2019_02_27_18_05
_13
2019_02_27_18_05
_13
2019_02_27_18_05
_14
2019_02_27_18_05
_14
2019_02_27_18_05
_14
2019_02_27_18_05
_14
2019_02_27_18_05
_14
2019_02_27_18_05
_14
2019_02_27_18_05
_14
2019_02_27_18_05
_14
2019_02_27_18_05
_15
2019_02_27_18_05
_15
2019_02_27_18_05
_15
2019_02_27_18_05
_15
2019_02_27_18_05
_15
2019_02_27_18_05
_15
2019_02_27_18_05
_15
2019_02_27_18_05
_15
2019_02_27_18_05
_15
2019_02_27_18_05
_16
2019_02_27_18_05
_16
2019_02_27_18_05
_16
Velocity
12.68113
9
12.68036
9
12.71031
6
12.71856
6
12.59914
6
12.65164
7
12.72220
7
12.72763
12.72763
12.72918
3
12.70486
2
12.73288
6
12.70126
4
12.66684
5
12.69170
6
12.71331
8
12.69477
4
12.64175
9
12.61284
1
12.61284
1
12.64730
5
12.64391
9
12.76073
9
12.71918
9
12.69252
5
12.65743
8
12.61265
2
12.59064
7
12.58723
6
12.62579
8
12.62579
8
12.58161
3
12.52192
2
FL
0.300231
0.345244
0.327239
0.336241
0.309234
0.300231
0.282227
0.304733
0.318236
0.318236
-0.29573
0.313735
0.322737
0.300231
0.286728
0.268723
0.345244
0.282227
0.340742
-0.29573
0.300231
0.304733
0.277725
0.313735
0.268723
-0.33174
0.300231
0.327239
0.304733
0.345244
0.291229
0.286728
0.309234
FD
0.091523
0.100541
0.077998
0.123083
0.073489
0.091523
0.096032
0.082506
0.091523
0.100541
0.105049
0.100541
0.096032
0.100541
0.096032
0.105049
0.087015
0.087015
0.127592
0.087015
0.091523
0.100541
0.087015
0.087015
0.100541
0.123083
0.096032
0.087015
0.087015
0.118575
0.096032
0.096032
0.118575
FM
cL
0.007971
0.005873
0.006922
0.005873
0.006398
0.005873
0.007971
0.111233
0.127926
0.120683
0.123843
0.116065
0.111753
0.103889
0.112078
0.117044
0.117016
0.109157
0.115293
0.119193
0.111485
0.106054
0.099053
0.127631
0.105212
0.127609
0.110752
0.111826
0.113563
0.101612
0.115538
0.099378
0.123364
0.112441
0.122984
0.114588
0.129029
0.108842
0.107914
0.117497
-0.00902
0.004825
-0.0043
0.008496
0.005873
0.007971
0.006922
0.005873
0.007447
0.006922
0.010593
0.008496
0.005873
0.009544
0.002203
0.006922
0.005873
-0.00902
0.007971
0.006922
0.007971
-0.00902
0.010069
0.008496
0.007971
0.008496
cD
0.033909
0.037254
0.028765
0.045333
0.027583
0.034067
0.03535
0.030345
0.033661
0.036969
0.038775
0.036947
0.035466
0.037334
cM
0.021094
0.015545
0.018235
0.015452
0.017152
0.015616
0.020959
0.023696
0.012675
0.011294
0.022398
0.015417
0.021028
Temperat
ure
22
22
22
22
22
22
22
22
22
22
22
22
22
0.037468
-0.01836
0.015517
0.019606
0.018279
0.028207
0.022726
0.015712
0.025392
0.005863
22
0.031836
-0.01809
22
0.032045
-0.01545
0.023826
0.021173
0.018518
0.021398
0.024227
0.026879
0.022679
0.021429
0.023057
22
0.03552
0.038722
0.032168
0.032438
0.047783
0.032587
0.034089
0.037181
0.045771
0.035965
0.032702
0.03272
0.044315
0.03589
0.036143
0.045054
22
22
22
22
22
22
22
22
22
22
22
22
22
22
22
22
22
Absolute
Pressure
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101779.4
95
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
101776.0
88
Relative
Humidity
Density
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.8
1.198883
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
41.7
1.198923
Kinemati
c
Viscosit
y
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
0.000015
4
Doc. Name: EdWin- OperationManual
Doc. No. : VWT-10.1-102
Rev. No. : R00
Status: RELEASE
Date: 21.05.2019
Page: 27 / 27
5.5. Disclaimer
The wind tunnel and software are not designed with every possible research perspective in mind and
are mainly for educating basic understanding of wind tunnel principles for students. Accuracy and
repeatability are influenced by a lot of factors (mainly dependent on the test body setup), and students
should be encouraged to analyze the setup and make error analysis themselves.