Browsing RPI Theses Open Access by Author "Sahni, Onkar"
Now showing items 1-20 of 25
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A parallel and adaptive interface tracking approach for evolving geometry problems
Yang, Fan (Rensselaer Polytechnic Institute, Troy, NY, 2019-12)Numerical simulations employing an interface tracking approach are desired in many evolving-geometry applications, particularly those involving fluid-structure and/or multiphase interactions with moving boundaries/interfaces. ... -
An investigation of the approximate optimal projection reduced-order models for elliptic partial differential equations
Hu, Mingyu (Rensselaer Polytechnic Institute, Troy, NY, 2016-05)Reduced-order modeling is often utilized in obtaining an approximate solution to a complex high-fidelity system. An essential step in constructing a reduced-order system is to project the original high-fidelity system onto ... -
Busemann-sears-haack hybrid geometries applied toward supersonic commercial vehicles for improved wave drag performance
Sklar, Andrew Wallace (Rensselaer Polytechnic Institute, Troy, NY, 2019-05)In this thesis, I have presented a new configuration for supersonic aircraft fuselages. I first demonstrated that the commercial Fluent code provides mesh converged, valid results for supersonic flows around various ... -
Conformal mesh adaptation on heterogeneous supercomputers
Ibanez, Daniel Alejandro (Rensselaer Polytechnic Institute, Troy, NY, 2016-12)Mesh adaptation is a technique which dynamically modifies the mesh being used to approximately solve a Partial Differential Equation (PDE) in order to improve aspects of the approximate solution including the computer time ... -
Coping with shock : numerical procedure for the detection and sorting of shocks in fluid flows
Tam, Isaac (Rensselaer Polytechnic Institute, Troy, NY, 2021-05)Within computational fluid dynamics (CFD) simulations, many complex flow phenomena can emerge. Accurately modeling these phenomena is often a primary motivating factor behind these simulations, and shocks are some of the ... -
Data-driven stochastic modeling of guided wave propagation and robust damage diagnosis
Ahmed, Shabbir (Rensselaer Polytechnic Institute, Troy, NY, 2022-05)Modern day civil, mechanical, and aeronautical structures are transitioning towards a continuous, online, and automated maintenance paradigm in order to ensure increased safety and reliability. The field of structural ... -
Development of in-series piezoelectric bending beam bimorph actuators for active flow control applications
Chan, Wilfred Keith (Rensselaer Polytechnic Institute, Troy, NY, 2016-08)In addition to physical testing, a quasi-static analytical model was developed and compared with experimental data, which showed close correlation for both free displacement and blocking force. Similarly, finite element ... -
Dynamic load control of a wind turbine blade using synthetic jets
Taylor, Keith Robert (Rensselaer Polytechnic Institute, Troy, NY, 2014-05)This study demonstrated that, through the introduction of periodic momentum near the leading edge of this model, the average tip deflection could be reduced under dynamic conditions. Furthermore, it was demonstrated that, ... -
Error-driven and predictive mesh control for adaptive simulations of incompressible two-phase flows
Zhang, Alvin (Rensselaer Polytechnic Institute, Troy, NY, 2019-12)adaptive approach becomes highly desirable. This is particularly the case for two-phase flows where interface evolution and dynamics are of interest. -
Experimental investigation of three-dimensional separated flows at low reynolds numbers on finite aspect ratio wings
Hayostek, Shelby Kateri-Rose (Rensselaer Polytechnic Institute, Troy, NY, 2021-08)Flow separation is a complex, three-dimensional phenomenon that leads to a loss in aerodynamic performance such as a decrease in lift and an increase in drag. It occurs when the flow detaches from a surface and creates a ... -
Feasibility of using dynamically oscillating surfaces to control Tollmien-Schlichting waves
Dell'Orso, Haley (Rensselaer Polytechnic Institute, Troy, NY, 2016-08)This work characterizes and controls Tollmien-Schlichting (T-S) waves by means of Piezoelectrically-Driven Oscillating Surface (PDOS) actuators, using Particle Image Velocimetry (PIV). A parametric study of PDOS actuator ... -
Flow control in a transonic diffuser through mass and vorticity injection to mitigate massive separation
Gartner, Jeremy (Rensselaer Polytechnic Institute, Troy, NY, 2017-05)An experimental flow control investigation was conducted in two test articles: an S-duct and a diffuser, both at high-subsonic conditions. -
Flow physics and sensitivity study of synthetic jets-based flow control of 3-D configurations
Monastero, Marianne C. (Rensselaer Polytechnic Institute, Troy, NY, 2018-05)Bridging the gap between sub-scale, fundamental studies of synthetic jet actuators on aerodynamic models and full-scale applications on actual vehicles requires a thorough understanding of how the synthetic jets interact ... -
Formation and shearing of drops with applications in biophysics and bioprocessing
Gulati, Shreyash (Rensselaer Polytechnic Institute, Troy, NY, 2017-12)Drops are self-contained systems which do not need solid walls as surface tension provides containment. Solid walls can have associated issues such as sorption, chemical and electrostatic effects which can complicate the ... -
High-order accurate partitioned schemes for conjugate heat transfer with advection-diffusion equations
Huang, Sijia (Rensselaer Polytechnic Institute, Troy, NY, 2022-07)This thesis presents a high-order accurate partitioned scheme for the solution of conjugate heat transfer (CHT) problems. The scheme is based on special second-order accurate CHAMP (Conjugate Heat transfer Advanced ... -
Improvement of high-speed coaxial rotor performance using redundant controls and camber morphing
Jacobellis, George (Rensselaer Polytechnic Institute, Troy, NY, 2018-12)CFD simulations were then undertaken for a rotor with reflex camber on the inboard sections of the blades. Two modified blade geometries were derived from the geometry of the X2 blade, one with a larger chord, greater ... -
Improving parallelism of scientific and engineering applications on heterogeneous supercomputers
Diamond, Gerrett (Rensselaer Polytechnic Institute, Troy, NY, 2021-08)The rising usage of heterogeneous supercomputers introduces both opportunities for increased parallelism and challenges for efficient usage of the available hardware. Applications running on heterogeneous supercomputers ... -
Influence of freestream and forced disturbances on the shear layers of a square prism
Lander, Daniel Chapman (Rensselaer Polytechnic Institute, Troy, NY, 2017-05)Flow around the square prism, an archetypal bluff body, has applications in all areas of fluid mechanics: vibration, mixing, combustion and noise production to name a few. It also has distinct importance to wind loading ... -
Novel residual-based large eddy simulation turbulence models for incompressible magnetohydrodynamics
Sondak, David (Rensselaer Polytechnic Institute, Troy, NY, 2013-08)The goal of this work was to develop, introduce, and test a promising computational paradigm for the development of turbulence models for incompressible magnetohydrodynamics (MHD). MHD governs the behavior of an electrically ... -
Numerical methods for fluid-structure interaction and free surface flows
Serino, Daniel A. (Rensselaer Polytechnic Institute, Troy, NY, 2019-05)In the final part of this thesis, an algorithm is developed for free surface flows driven by gravity and surface tension. Deforming composite grids are used to handle the motion of the free surface and the governing equations ...