STEP-BY-STEP INSTRUCTION FOR EXAMPLE 5

 

The sample PIV recording pair was taken in a bubbly water two-phase flow experiment. The image size is 434x632 pixels. The corresponding measurement area is 18.8-mm x 27.4-mm. The time interval is 0.8 ms.

 

Step 1: Load digital PIV recording pair and phase masks

- Execute file “Edpiv.exe” - The start window is shown on the screen;

- Select menu “File \ Open recording 1” to open “…\ PIVsamples \ 5_BubblyWaterFlow \ k29_1.bmp”;

- Select menu “File \ Open recording 2” to open “…\ PIVsamples \ 5_BubblyWaterFlow \ k29_2.bmp”;

- Select menu “File \ Import mask 1” to open “…\ PIVsamples \ 5_BubblyWaterFlow \ mask1.bmp”;

- Select menu “File \ Import mask 2” to open “…\ PIVsamples \ 5_BubblyWaterFlow \ mask2.bmp”;

Step 2: Determine imaging scale and time interval

- Click menu “Edit / Scale & time” in the start window to open dialogue box “Imaging scale / time interval”;

- Select radio button mm;

- Input 18.8 in edit box “Reading on ruler”;

- Input 434 in edit box “Corresponding pixels”;

- Input 800 in edit box “Time interval [mu-s]”;

- Press “OK” button to return to start window.

Step 3: Setup evaluation parameters for continuous phase

- Click menu “Edit / Evaluation settings” in the start window to open the “Evaluation settings” window;

- Setup parameters as follows
Method & algorithm:
PIV
Ellipse window: Selected
Recording type: Single recording (pair)
Exposure type:
Single
Flow type:
Two phase
Phase type:
Continuous.
Initial window shift:
(X,Y), X=0, Y=0
Interrogation grid:
8x8
Error limits:
Dx=2.0, Dy=3.0
Iteration number:
0 (Initial), 6 (Final) 
Window width :
32 (Initial), 32 (Final)
Window height :
32 (Initial), 32 (Final)
Search radius:
8

- Close “Evaluation settings” window.

Step 4: Evaluate PIV recording pair for continuous phase

- Press button “Evaluation” in the start window;

- Click menu “Edit \ Grid structure \ Regular” - Dialogue box “Regular evaluation grid” appears;

- Push button “Reset grid” and then press button “OK”;

- Click menu “Start” in “Evaluation” window;

- Answer “Yes” to question “Do you want to start an evaluation?”

- Wait until the evaluation is completed;

- Press “OK” button to close the dialogue box that notices the end of the evaluation.

Step 5: Save evaluation result

- Click menu “File \ Save data” - Dialogue box “Save evaluation results” appears;

- Find a desired folder, type in a file name in the dialogue box;

- Press button “Save” to complete the saving procedure.

Step 6: Plot vector map

- Close EDPIV;

- Use TECPLOT to make plots.