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Author ORCID Identifier
https://orcid.org/0000-0003-2446-0186
AccessType
Open Access Dissertation
Document Type
dissertation
Degree Name
Doctor of Philosophy (PhD)
Degree Program
Mechanical Engineering
Year Degree Awarded
2022
Month Degree Awarded
February
First Advisor
Blair PErot
Second Advisor
David Schmidt
Third Advisor
Jon G. McGowan
Fourth Advisor
Hans Johnston
Subject Categories
Aerodynamics and Fluid Mechanics | Discrete Mathematics and Combinatorics | Fluid Dynamics | Numerical Analysis and Scientific Computing
Abstract
Hybrid particle-mesh numerical approaches are proposed to solve incompressible fluid flows. The methods discussed in this work consist of a collection of particles each wrapped in their own polygon mesh cell, which then move through the domain as the flow evolves. Variables such as pressure, velocity, mass, and momentum are located either on the mesh or on the particles themselves, depending on the specific algorithm described, and each will be shown to have its own advantages and disadvantages. This work explores what is required to obtain local conservation of mass, momentum, and convergence for the velocity and pressure in a particle-mesh CFD simulation method. Current particle methods are explored and analyzed for their benefits and deficiencies, and newly developed methods are described with results and analysis. A new method for generating locally orthogonal polygonal meshes from a set of generator points is presented in which polygon areas are a constraint. The area constraint property is particularly useful for particle methods where moving polygons track a discrete portion of material. Voronoi polygon meshes have some very attractive mathematical and numerical properties for numerical computation, so a generalization of Voronoi polygon meshes is formulated that enforces a polygon area constraint. Area constrained moving polygonal meshes allow one to develop hybrid particle-mesh numerical methods that display some of the most attractive features of each approach. It is shown that this mesh construction method can continuously reconnect a moving, unstructured polygonal mesh in a pseudo-Lagrangian fashion without change in cell area/volume, and the method's ability to simulate various physical scenarios is shown. The advantages are identified for incompressible fluid flow calculations, with demonstration cases that include material discontinuities of all three phases of matter and large density jumps.
DOI
https://doi.org/10.7275/26841056
Recommended Citation
Chartrand, Chris, "Moving Polygon Methods for Incompressible Fluid Dynamics" (2022). Doctoral Dissertations. 2438.
https://doi.org/10.7275/26841056
https://scholarworks.umass.edu/dissertations_2/2438
Rising bubble – high resolution
bubble_low_res.mkv (12151 kB)
Rising bubble – low resolution
dam_break_low_res.mkv (5213 kB)
Dam break – low resolution
dam_break_high_res.mkv (5060 kB)
Dam break – high resolution
LO_0.022.mkv (10596 kB)
Lamb Oseen Vortex
raft_high_res.mkv (54815 kB)
Floating raft – high resolution
raft_low_res.mkv (29964 kB)
Floating raft – low resolution
raft_zoom.mkv (103520 kB)
Floating raft – high resolution zoom
raft-render.mkv (7995 kB)
Floating raft – high resolution rendered
slosh.0.01.mkv (12263 kB)
Sloshing wave – dx = 0.01
slosh.0.02.mkv (13143 kB)
Sloshing wave – dx = 0.02
slosh.0.0027.mkv (11765 kB)
Sloshing wave – dx = 0.0027
slosh.0.0055.mkv (11391 kB)
Sloshing wave – dx = 0.0055
MP_2D_tor_ref_0.32_0.01_crop.avi.mp4 (8518 kB)
Torsion Flow over cylinder – Re=0.64
MP_2D_tor_ref_32_crop.avi.mp4 (4286 kB)
Torsion Flow over cylinder – Re=64
MP_2D_vor_ref_0.32_0.01_crop.avi.mp4 (8878 kB)
Voronoi Flow over cylinder – Re=0.64
MP_2D_vor_ref_32_crop.avi.mp4 (4670 kB)
Voronoi Flow over cylinder – Re=64
voronoi.avi.mp4 (19111 kB)
Voronoi Reconnection
colors.0.01.mkv (24898 kB)
Taylor Green Vortex mixing – dx = 0.01
colors.0.02.mkv (39093 kB)
Taylor Green Vortex mixing – dx = 0.02
colors.0.0027.mkv (84260 kB)
Taylor Green Vortex mixing – dx = 0.0027
colors.0.0055.mkv (37818 kB)
Taylor Green Vortex mixing – dx = 0.0055
velocity_viridis.0.01.mkv (3204 kB)
Taylor Green Vortex velocity – dx = 0.01
velocity_viridis.0.02.mkv (5085 kB)
Taylor Green Vortex velocity – dx = 0.02
velocity_viridis.0.0027.mkv (2198 kB)
Taylor Green Vortex velocity – dx = 0.0027
velocity_viridis.0.0055.mkv (3033 kB)
Taylor Green Vortex velocity – dx = 0.0055
Included in
Aerodynamics and Fluid Mechanics Commons, Discrete Mathematics and Combinatorics Commons, Fluid Dynamics Commons, Numerical Analysis and Scientific Computing Commons