Hot- wires automatic calibration
The Streamline Pro Automatic Calibrator (Dantec Dynamics) general data sheet
is designed for calibration of wire and film probes in air at velocities up to 300 m/s. The velocity range depends on the diameter of the nozzle.
The following represent the velocity ranges for each nozzle:
0:1400 mm2 ( 42 mm) for 0.02 - 0.5 m/s
I:120 mm2 ( 12 mm) for 0.5 - 60 m/s
II:60 mm2 ( 8.7 mm) for 5 - 120 m/s
III:20 mm2 ( 5 mm) for 5 m/s - >300m/s.
The calibrator operates on compressed air. Air must be available in a sufficient amount at a proper pressure level range within 6 and 8 bar. The air has to be always filter when operating the calibrator. The filtering unit is inserted between the compressor and the calibrator. To supply air at a desired pressure to the calibrator the pressure hose has to be connected to the calibrator first, and then the pressure reducer has to be adjust to the target pressure (6-8 bar). The required power for the calibrator is 24 V DC (0.8 A).
Pitch-yaw manipulator for directional calibrations
Multiple sensor probes 2D x-shaped TSI 1241-20Hot wires catalog are used to perform 2 or 3 component velocity measurements using the directional sensitivity.The probes have to be connected to the CTA. For more information about CTA, please refer to CTA. During the directional calibration the probe is yawed and rolled, around two axes. The pitch-yaw manipulator motors are connected to the motorized unit through serial cables Manipulator connections sheet
Check of the jet velocity
| Target velocity (m/s) | Pitot tube velocity (m/s) | Calibrator reading (m/s) | Error % |
|---|---|---|---|
| 0.5 | 0.471 | 0.509 | 7.6 |
| 1 | 0.992 | 1.007 | 1.5 |
| 2 | 1.948 | 2.000 | 2.6 |
| 3 | 2.957 | 3.061 | 3.5 |
| 5 | 4.866 | 5.027 | 3.3 |
| 7 | 6.508 | 6.974 | 7.1 |
| 9 | 8.260 | 8.932 | 8.1 |
The pressure transducer used for Pitot tube measurements is First Sensor, unidirectional with a 50 Pa pressure range. The relative humidity has been measured with the hygrometer. While the temperature and the atmospheric pressure have been acquired from the calibrator measurements. Moreover, a thermocouple has been used as a reference measurement for the temperature.
Controlling the Automatic Calibrator
Procedure
1. Plug the hose into Air Supply connector and set the pressure to 6-8 bar and (as described above);
2. Connect the Ethernet port to the computer;
3. Define Ethernet as 192.168.0.1 (for any other channel other than 10 or 11 which are already taken);
4. Connect the cable for rotation and pitch\yaw motors between the manipulator and the control box;
5. Switch on the controller;
6. Make sure the probe coordinate system and the calibrator coordinate system are oriented the same way 
7. The hotwires probe should be aligned with the entrance of the nozzle of the calibrator.
8. Remember to check the resistance of the probes prior to use and set the CTA channels accordingly. cta
Automatic Calibration m.files
Make sure you have downloaded the Matlab Instrument control ToolBox.
Jet and Manipulator control codes Jet control, Manipulator control:
1. Open the zip folder basic_jet_control. Run BasicJetCommands.m.
For further reference, please consult these files:
h834p138.pdf imc4m_handbook.pdf mc1-10-programming-instructions.pdf
Complete codes for:
1. Automated 3D calibration automatedcalibration_3d.zip :automatedcalibration_3d.zip |}}}} . Make sure to run AutomatedProcedure.m (you can change the number of points, velocities, set to A\D channels to read etc.)
Conversion from Voltages to Velocities
2. Automated 2D calibration (only Pitch or Yaw) 2D calibration
Conversion from Voltages to Velocities VolttoVelConversion
3. Lookup table calibration method lookuptable_tj2_tj3.zip