An INCOMPLETE list of related publications:
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For a list of more recent publications by S.A. Kinnas and colleagues please refer to http://cavity.ce.utexas.edu/~kinnas/publ_kinnas.html

Computational techniques for the Analysis and Design of Cavitating Propeller Blades by P.E. Griffin, Master's Thesis, UT Austin, May 1998.

Development of Face and Mid-chord Cavitation Models for the Prediction of Unsteady Cavitation on a Propeller by A.C. Mueller, Master's Thesis, UT Austin, May 1998.

The Prediction of Unsteady Sheet Cavitation by S.A. Kinnas, invited paper at the CAV'98, 3rd International Symposium on Cavitation, Grenoble, France, April '98.

Propeller Wake Alignment Models in Uniform and Inclined Flow by S.A. Kinnas, and S. Pyo, SNAME Propellers and Shafting '97 Symposium, September 23-24, 1997, Virginia Beach, VA.

Numerical Propeller Tunnel by J.-K. Choi and S.A. Kinnas, SNAME Propellers and Shafting '97 Symposium, September 23-24, 1997, Virginia Beach, VA.

Computational Tools for the Analysis and Design of High Speed Propulsors by S.A. Kinnas, P.E. Griffin, and A.C. Mueller International CFD Conference, May 29-31, 1997, Ulsteinvik, Norway.

Cavitating Propeller Analysis Inside of a Tunnel by J.K. Choi and S.A. Kinnas, ASME Fluids Engineering Division Summer Meeting , June 1997, Vancouver, Canada.

A Low-Order BEM for Internal Flows - Application to the Flow Through a Water-jet Inlet by S.A. Kinnas, IABEM Workshop on Fundamental Solutions in Boundary Elements : Formulation and Integration, June 1997, Sevilla, Spain.

A High-Order BEM Based on the "Saw-tooth" Correction - Application to the Structural Analysis of Cavitating Hydrofoils by S.A. Kinnas and B. Gucun, IABEM Workshop on Fundamental Solutions in Boundary Elements : Formulation and Integration, June 1997, Sevilla, Spain.

Experiment and Viscous Flow Analysis on a Partially Cavitating Hydrofoil by W.H. Brewer and S.A. Kinnas, accepted, to appear in Journal of Ship Research , 1997.

Design of Cavitating Propeller Blades in Non-uniform Flow by Numerical Optimization by S. Mishima, PhD Thesis, June 1996.

High-speed propulsor blades are often experiencing moderate to substantial amounts of unsteady cavitation, and up to now have been designed via design methods for non-cavitating blades, combined in a trial-and-error manner with methods for the analysis of cavitating flows.
In this thesis a numerical non-linear optimization algorithm is developed for the automated systematic design of cavitating blades. The objective and constraint functions in the optimization process are expressed in terms of the design variables via linear approximations of the results from an existing lifting-surface analysis method, in the first stage of the algorithm, and quadratic approximations in the final stage. In this way the number of required geometries to be analyzed and the associated computational effort are minimized. The developed methodology is implemented in a modular manner so that future improvements in the modeling of cavitating flows can be readily incorporated. The proposed algorithm is validated with several known non-linear optimization test problems.
The method is first applied to the design of efficient two-dimensional partially and supercavitating hydrofoil sections and the results are compared to those from a previously developed optimization procedure.
Then, the method is applied to the design of propeller blades in uniform flow. The blade mean camber surface is defined via a cubic B-spline polygon net in order to facilitate the handling of the geometry, and to reduce the number of the design parameters. Non-cavitating blade geometries designed by the present method are directly compared to those designed via an existing lifting-line/lifting-surface design approach.
Finally, the optimization algorithm is applied to the design of cavitating blades in non-uniform flow. The objective of the design is to obtain maximum propeller efficiency for given conditions by allowing controlled amounts of sheet cavitation. Several constraints on the unsteady cavity characteristics, such as the area of cavity planform and the amplitudes of the cavity volume velocity harmonics, are incorporated in the optimization technique. The effect of the constraints on the efficiency of the propeller design is demonstrated with various test cases.

A Numerical Optimization Technique Applied to the Design of Two-Dimensional Cavitating Hydrofoil Sections by S. Mishima and S.A. Kinnas, Journal of Ship Research, vol. 40, March '96 pp. 28-38

A numerical nonlinear optimization technique is applied to the systematic design of two-dimensional partially or super-cavitating hydrofoil section. The design objective is to minimize the hydrofoil drag for given lift and cavitation number. The hydrodynamic analysis of the cavitating hydrofoil is performed in non-linear theory, via a low-order potential-based panel method. The effects of viscosity are taken into account via a frictional drag coefficient applied to the wetted foil surface. The total drag, lift, cavitation number, and other quantities involved in the the imposed constraints, are expressed in terms of quadratic functions of the main parameters of the hydrofoil geometry, angle of attack, and the cavity length. The optimization is based on the method of multipliers by coupling the Lagrange multiplier terms and the penalty function terms. The robustness and convergence of the method are extensively investigated, and the results are compared to those from applying other design methods.

A Time Marching Boundary Element Method for the Prediction of the Flow Around Surface Piercing Hydrofoils by C. Savineau, Master's Thesis, February 1996.

Application of Unsteady Vortex/Source Lattice Method on Supercavitating Propellers by T. Kudo and S.A. Kinnas, 24th American Towing Tank Conference, College Station, TX, 1995

A computational method (HPUF-3A) for the prediction of unsteady propeller blade sheet cavitation is applied to the analysis of supercavitating propellers in steady flow. The method is incorporating a vortex and source lattice scheme. To allow for the treatment of very long supercavities, improvements were introduced in the cavity extent iteration algorithm and in the force calculation procedure. The modeling of the separated flow behind trailing edges with non-zero thickness (very often the case for supercavitating blade sections) was also included. Results of this method are extensively validated and compared with those of another method, as well as with measurements from a supercavitating propeller experiment.

A Numerical Formulation Applicable to Surface Piercing Hydrofoils and Propellers by C. Savineau and S.A. Kinnas, 24th American Towing Tank Conference, College Station, TX, 1995

An International Consortium on High-Speed Propulsion by S.A. Kinnas, Marine Technology, July 1996

Recent demands for higher speed ocean vehicles and, at the same time, for more efficient &propulsion, have made the appearance of cavitation inevitable. Thus, contemporary hydrofoil or propeller blade designs must take advantage of controlled cavitation in order to increase the efficiency of propulsion. An International Consortium on Cavitation Performance of High-Speed Propulsors has been put together by the author. The ultimate objective of this effort is to develop a new generation of reliable and user-friendly computational tools for the analysis and systematic design of efficient cavitating hydrofoils or propulsors. Fifteen participants have joined this consortium thus far. They include research centers, propeller manufacturers, shipyards, and high-speed boat industriesfrom the U.S., Europe, and Asia. An overview of the research plan and the approach for some of the research tasks are presented.

Theory and Numerical Methods for the Hydrodynamic Analysis of Marine Propulsors (without figures). by S.A. Kinnas, in Advances in Marine Hydodynamics, Computational Mechanics Publications, 1996

Recent computational techniques for the hydrodynamic analysis of marine propulsors are described. The involved formulations and numerical methods are capable of handling arbitrary blade, hub and duct geometries, general inflows, and the presence of blade sheet cavitation.

Experimental and Computational Investigation of Sheet Cavitation on a Hydrofoil

A partially cavitating hydrofoil experiment is performed at the MIT Variable Pressure Water Tunnel to ultimately assess the validity of several computational methods. The measurements are compared to the numerical results from a coupled, nonlinear, inviscid cavity analysis method and a boundary layer solver.

Non-linear Analysis of Viscous Flow Around Cavitating Hydrofoils

The formulation of a general potential-based boundary element method developed for the non-linear analysis of inviscid cavitating flow around hydrofoils or propeller blades.

Application of Optimization Techniques to the Design of Cavitating Hydrofoil and Wings. S.A. Kinnas, S. Mishima, C. Savineau. In Procedings of International Symposium on Cavitation. Deauville, France. May 2-5 1995.

The design of cavitating hydrofoils or wings is performed in a systematic fashion, by using a non-linear optimization technique. The cavity flow is treated within non-linear theory during the design process, with the effects of viscosity also included, in an iterative sence. Constraints are imposed in order to avoid non-physical solutions. The effects of three-dimensional flow are included in the case of elliptic planform wing, via the lifting line approach. Results are presented for different thickness forms in partial cavitation and for one camber form in super-cavitation, with or without the effects of the free-surface included. Optimal solutions are given for a wide range of combinations of lift and cavitation number, in partially or super-cavitating flow, or in fully wetted flow. The regions in which a partially cavitating, a super-cavitating, or a fully wetted hydrofoil, is the most efficient solution, are finally presented.

Experimental and Analytical Investigation of a Cavitating Hydrofoil: The TriFoiler as a Case Study. C. Savineau, J. Paschkewitz. Presented at the New England Section SNAME Meeting, MIT. February 3 1994.

A full scale hydrofoil wing of a high speed sail boat was tested in MIT's Marine Hydrodynamics Cavitation tunnel. Force and flow measurements were made at several angles of attack, and cavitation numbers. Lift coefficients were calculated using: (1) load cell force measurements and (2) momentum flux integration from flow measuremnts made with a Laser Doppler Velocimeter (LDV.) Cavitation growth with varying angle of attack and cavitation number was measured using the LDV. Numerical calculations, using a low-order, potential-based boundary element method, were made to simulate the experimental conditions.

Systematic Design of Optimum Cavitating sections. S.A. Kinnas S. Mishima. Second International Symposium on Cavitation., University of Tokyo, Tokyo, Japan. April 5-7, 1994.

A non-linear optimization technique is presented for the systematic design of cavitating hydrofoils. The geometry of the optimum foil and its angle of attack are determined by minimizing the resulting drag for given lift and cavitation number. The forces and the cavitation number are determined in the context of non-linear cavity theory viea polynomial expansions with respect to the involved parameters. The effects of viscosity on the predicted forces and cavity size are also included within the optimization process, in an iterative sence.

A Numerical Nonlinear Analysis of the Flow Around 2-D and 3-D Partially Cavitating Hydrofoils (without figures) by S.A. Kinnas and N.E. Fine. Journal of Fluid Mechanics Vol. 254, 1993, pp. 151-181.

The partially cavitating 2-D hydrofoil problem is treated in nonlinear theory by employing a low-order potential-based boundary element method. The cavity shape is determined in the framework of two independent boundary value problems; in the first, the cavity length is specified and the cavitation number is unknown, and in the second the cavitation number is known and the cavity length is to be determined. In each case, the position of the cavity surface is determined in an iterative manner until both a prescribed pressure condition and a zero normal velocity condition are satisfied on the cavity. An initial approximation to the nonlinear cavity shape, which is determined by satisfying the boundary conditions on the hydrofoil surface rather than on the exact cavity surface, is found to differ only slightly from the converged nonlinear result. The boundary element method is then extended to treat the partially cavitating 3-D hydrofoil problem. The three dimensional kinematic and dynamic boundary conditions are applied on the hydrofoil surface underneath the cavity. The cavity planform at a given cavitation number is determined via an iterative process until the thickness at the end of the cavity at all spanwise locations becomes equal to a prescribed value (in our case, zero). Cavity shapes predicted by the present method for some 3-D hydrofoil geometries are shown to satisfy the dynamic boundary condition to within acceptable accuracy. The method is also shown to predict the expected effect of foil thickness on the cavity size. Finally, cavity planforms predicted from the present method are shown to be in good agreement to those measured in a cavitating 3-D hydrofoil experiment, performed at MIT's cavitation tunnel.