In this section a pair of PIV recordings from a micro-scale pipe flow test is used to demonstrate the application of adaptive interrogation grid and adaptive interrogation window. The width of the micro channel is 0.1 mm, and it takes 153 pixels in the digital image. The time interval is 10 micro seconds. A mask image was made to determine the flow boundary.


Step 1: Load digital PIV recordings

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

- Select menu “File \ Open recording 1” to open “…\ PIVsamples \ b_AdaptiveGrid&Winddow \ bmp_0049A.bmp”;

- Select menu “File \ Open recording 2” to open “…\ PIVsamples \ b_AdaptiveGrid&Winddow \ bmp_0049B.bmp”;

- Select menu “File \ Import B-mask” to import “…\ PIVsamples \ b_AdaptiveGrid&Winddow \ BG-mask.bmp”.

Step 2: Input imaging scale & time interval

- Click menu “Edit / Sacle&Time” to open box “Imaging scale/time interval” and to
set length unit to
0.1 in edit box “Reading on ruler”
153 in edit box “Corresponding pixels”
10 in edit box “Time interval [mu-s]”;

- Press “OK” button to close dialogue box “Imaging scale/time interval”.

Step 3: Setup evaluation parameters

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

- Setup parameters as follows
Method & algorithm:
Ellipse window: Selected
Boundary mask:
Recording type:
Single recording (pair)
Exposure type:
Flow type:
One phase
Initial window shift:
X=0, Y=0
Interrogation grid:
Width= 16, Height= 8
Error limits:
Dx=3, Dy=3
Iteration number:
0 (Initial), 6 (Final) 
Window width:
48 (Initial), 48 (Final) 
Window height:
24 (Initial), 24 (Final) 
Search radius:
Adaptive interrogation window: Grid, Reshape selected 

- Click menu “Image filter” to select
Digital image filter:
Filter: w=
11 , h= 11

- Close “Evaluation settings” window.

Step 4: Evaluate the PIV recording pair

- Press button “Evaluation” in the start window;

- Select menu “Edit \ Grid structure \ Regular” to open dialogue box “Regular evaluation grid” and press “Reset grid” button when “Reduced” checked, and then press button “OK”;

- Click menu “Edit \ Grid reconstruction \ Bended channel \ Pipe mask #1”;

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

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

- Wait until the evaluation is completed;

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

Step 5: Save evaluation results

- 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.