Experimental Study of Vortex-Vortex Interaction on a Pair of Cambered Hydrofoil and a Propeller in B
Abstract
Vortex-vortex interaction governs much of the interesting and not yet fully understood dynamics during a vehicle maneuver, including, cavitation inception mechanisms and evolution and unsteady forces on propeller, shaft, and vehicle. To address this knowledge gap,, we will conduct two sets of experiments at the large free surface cavitation tunnel at CNR-INM. The first set concerns the study o,f vortex-vortex interaction and how they influence vortex dynamics and instability, cavitation inception and performance for a pair,of cambered hydrofoils at different separation distance and speed. The second set concerns the vortex-vortex interactions in the pr,opeller region of a fully appended underwater vehicle at different drift angles, speed, and depth.The main objective of the research, is to fully understand the fundamental underlying mechanisms of vortex-vortex interaction and how they influence vortex dynamics an,d instability, cavitation inception and performance. Specific focus of the research will be: 1.to further develop and validate a met,hodology to condition global signals (e.g. hull force and moments, propeller blade/shaft loads, ship?s attitude, time history of the, hydrodynamic forcing) to local characteristics of the fluid dynamic field around the propeller/hull, on the basis of synchronous ve,locimetry, dynamometric, vibration, deformation, vessel attitude measurements. 2.to perform a systematic experimental survey by Tomo,graphic Particle Image Velocimetry and flow visualizations to investigate the interaction mechanisms for a canonical two-vortex syst,em generated by a pair of cambered hydrofoils, including vortex stretching and pressure drop, and their effect on cavitation, when v,arying vortex distances, strengths and orientations. 3.to perform a comprehensive experimental survey involving conditioned detailed, flow measurements and propeller blade/shaft load and deformation measurements to investigate the cause-effect relation between the,hydrodynamic forcing and the propeller/hull response for a reference propeller/hull configuration, during a maneuver. 4.to investiga,te propeller and hull forces and moments to further understand the underlying mechanisms of vehicle response to propeller lateral fo,rces and related moments during a maneuver.5.to collect archival quality experimental data, including detailed flow measurements by,advanced optical techniques along with unsteady force and moment measurements on propeller, to support/improve CFD modelling and pre,dictions. Geometries and results of the two experiments will be shared with US collaborators via appropriate data sharing platforms,and/or via a dedicated repository with limited-access to US collaborators and ONR authorized persons. In particular, twin foil data,will be shared and used in the context of the NATO Science & Technology Organization (STO) Applied Vehicle Technology (AVT) activate,s for the assessments of numerical methods for turbulent cavitating flows (i.e. NATO-AVT 320 and its continuation).The project is or,ganized in four major tasks and has a duration of three years.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Oct 07, 2022
- Source ID
- N000142212827
Entities
People
- Mario Felli
Organizations
- Consiglio Nazionale delle Ricerche
- Office of Naval Research
- United States Navy