1. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Closed-loop test configuration for the simulation of a hydraulic powerplant with microturbine and conical diffuser Figure Legend:

2. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Microturbine runner (top) and volute geometry (bottom) Figure Legend:

3. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Close view of the draft tube cone with an inlet and outlet diameter of D1¯ = 31mm and cone D cone = 57 mm. The straight part measures L 1 = 50.8 mm and the conical part has a length of L 2 = 186 mm with a half-angle of 4 deg. Figure Legend:

4. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Draft tube flow visualization showing one period T of the vortex rope oscillation: (a) t = 0, (b) t = 0.11 · T, (c) t = 0.22 · T, (d) t = 0.33 · T, (e) t = 0.44 · T, (f) t = 0.55 · T, (g) t = 0.66 · T, (h) t = 0.77 · T, (i) t = 0.88 · T, and (j) t = T Figure Legend:

5. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Amplitude (solid line) and phase angle (dashed line) of the cross-spectral power density between the pressure sensors p 3 and p 6 Figure Legend:

6. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Control volume in the draft tube containing the volume V c Figure Legend:

7. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Draft tube cone in cavitation-free conditions with sections I, II, III, IV, and V for image processing Figure Legend:

8. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Subtraction of a reference image from a video frame (top) and masked binary conversion (bottom) for the edge detection in sections I, III, and V Figure Legend:

9. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Pixel value curve along a vertical line for the edge detection in sections II and IV. The dashed horizontal lines represent the locations of the estimated cavity edges according to the local minima of the pixel value curve. Figure Legend:

10. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 low-pass filtered c p from p 2 with instant phase (dashed line) and bottom: mean phase average with standard deviation (vertical error bars) Figure Legend:

11. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Nondimensional volume Vc* estimated from flow visualization (point markers) with low-pass filtered signal (solid line) as a function of the number of runner revolutions Figure Legend:

12. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Nondimensional vortex rope volume Vc* from flow visualization, wall-pressure coefficient from p 2, and nondimensional discharge fluctuations Q̃1 ∗, and Q̃2 ∗ as a function of the number of runner revolutions Figure Legend:

13. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Nondimensional, centered Vc* from flow visualization (point markers) and from discharge measurements (dashed line) as a function of the number of runner revolutions Figure Legend:

14. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Mean pressure phase-averaged vortex rope volume (top) and discharge fluctuations (bottom) with standard deviations (vertical error bars) Figure Legend:

15. Date of download: 6/20/2016 Copyright © ASME. All rights reserved. From: Measurement of the Self-Oscillating Vortex Rope Dynamics for Hydroacoustic Stability Analysis J. Fluids Eng. 2015;138(2):021206-021206-8. doi:10.1115/1.4031778 Vortex rope volume as a function of the upstream and downstream discharge fluctuations during one mean period of the pressure oscillation Figure Legend: