Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 50 for “"complex flows"”.
-
Turbulence Modelling for Complex Flows in Turbomachinery
… it can be a more reliable tool for modelling complex flows in turbomachinery. To achieve this goal, a three-dimensional (3D) flow phenomenon that embodies many key features of turbomachinery flows, that is, the corner separation flow often found in axial compressor stators, is selected as the …
-
Analysis of complex flows in safety valves using CFD
… CFD solvers to accurately capture the array of complex flow dynamics which exist during the operation of various types of PRV’s. Furthermore, to achieve confidence in the capability of the CFD models developed; it was required for experimental validation work to be performed. Initially a 3D …
-
On the dynamics of rigid and flexible structures under complex flows
… in tandem arrangements under uniform flows at various Cauchy numbers $Ca\in [15,\ 77]$, and spacing $s_x=\Delta x/h=0.5,\ 1$ and 2. Results show that the oscillations of the upstream plate were dominated by its natural frequency. However, the motions of the downstream plate were …
-
Large Eddy Simulations of high Reynolds number Complex Flows with Synthetic Inlet Turbulence
… need to be surmounted for general application to complex high Reynolds number turbulent flows. The primary challenge in wall bounded flows is the need for very fine grids in the vicinity of walls, which makes LES impractical at high Reynolds numbers. An additional challenge is the accurate …
-
Development of a Virtual Scientific Visualization Environment for the Analysis of Complex Flows
… of vortical, spatio-temporally developing flows with complex fluid-structure interactions. This VE was used to study flows in the cardiovascular system, particularly for flow through mechanical heart valves and inside the heart left ventricle (LV). The simulation provides three-dimensional …
-
The stability of viscoelastic fluids in complex flows : the role of shear and extensional rheology
… This thesis focuses on the stability of two complex non-Newtonian flows of dilute polystyrene solutions: the viscometric flow between a rotating cone-and-plate and the flow through an axisymmetric contraction-expansion. Torsional shear flows of elastic fluids with closed streamlines can …
-
Development of an efficient finite volume computational platform for the simulation of complex flows of complex fluids governed by the Rolie-Poly model
The flow of non-Newtonian fluids, also known as complex fluids, is an important area of fluid mechanics due to their applications in industries such as food processing, mining, chemical and plastic industries. It is therefore essential to understand the flow and general behaviour of such fluids. …
-
Algebraic Multigrid for Discrete Differential Forms
… for sensor network coverage, visualization of complex flows, surface parameterization, and the design of vector fields on meshes. In this thesis we describe efficient and scalable numerical solvers for discrete k-form problems. Our approach is based on the principles of algebraic multigrid …
-
A nonlocal dense granular flow model implemented in the material point method
… has shown great predictive capability for dense flows when implemented in the finite element framework, but limitations of FEM prevent application of the model to truly large scale, inhomogeneous deformations. We show that these FEM results may be replicated in the MPM framework through the …
-
Implementation and Validation of the ζ-F and ASBM Turbulence Models
… are not adequate for accurate prediction of complex flows. This includes flows with high streamline curvature, strong rotation and separation regions. Unfortunately, due to their ease of use in the commercial CFD tools, the models are used frequently for complex flows. Modifications have been …
-
Quantification of structural uncertainties in RANS turbulence models
… channel. To model the uncertainty in more complex flows, the procedure is repeated for a collection of flows through randomly generated geometries.
-
A Computational Study of Axial Compressor Rotor Casing Treatments and Stator Land Seals
… allowed for greater understanding of the complex flows inherent in each of these features. It was found that rotor tip vortex control plays a large part in the surge margin gains from a circumferential groove casing treatment. The efficiency gains of knife seals were dependent primarily on …
-
Complex fluid dynamical computations via the Finite Volume Method
Numerical simulations of the complex flows of viscoelastic fluids are investigated. The viscoelastic fluids are modelled, primarily, via the Johnson-Segalman constitutive model. Our Numerical approach is based on finite volume method, based on the Johnson-Segalman constitutive model and implemented …
-
A Perfectly Matched Layer Method for the Navier-Stokes equations
… and its performance is assessed when applied to complex flows; in particular, a viscous cavity flow is investigated. Stabilizing adjustments to the method are made, and future work is indicated for increased utility and flexibility of the method.
-
Development of a Hybrid Particle Continuum Solver
<p>When simulating complex flows, there are some physical situations that exhibit large fluctuations in particle density such as: planetary reentry, ablation due to arcing, rocket exhaust plumes, etc. When simulating these events, a high level of physical accuracy can be achieved with kinetic …
-
Theoretical And Computational Study of Steady Transonic Flows of Bethe-Zel\'dovich-Thompson Fluids
We examine steady transonic flows of Bethe-Zel\'dovich-Thompson (BZT) fluids over thin turbine blades or airfoils. BZT fluids are ordinary fluids having a region of negative fundamental derivative over a finite range of pressures and temperatures in the single phase regime. We derive the transonic …
-
Modeling Flow-Induced Microstructure of Inhomogeneous Liquid-Liquid Mixtures
… Example calculations show that, even in simple flows, microstructural effects can cause complex rheological behaviors in dispersions. Finally, these models are applied to complex flows of dispersions using the finite element method. Microstructure is predicted as a field variable in temporally- …
-
A hybrid computational and analytical model of irrigation drip emitters
… the fluid mechanics of duct and turbulent flows are used to predict the net flow rate out of the emitter. The final model is verified for three distinct emitter geometries. The hybrid model presented in this paper has wide applicability - it can be applied to asymmetrical emitter geometries …
Page 1 of 3