Force data for a flapping foil energy harvester with active leading edge motion operating in the low reduced frequency range is collected to determine how leading edge motion affects energy harvesting performance. The foil pivots about the midchord and operates in the low reduced frequency range of 0.06, 0.08, and...
Lake Kinneret is Israel's only fresh water lake (unless you count the Dead Sea). It spans roughly 20km from north to south, and about 12km at its widest east west extent. It is not quite 50m deep at its deepest point. In late spring, the lake stratifies significantly and remains...
It is hypothesized that extracting the vapor from two-phase flow in a microchannel will result in a lowered pressure drop required to drive the flow. The goal of this thesis is to construct an experimental device that will test this hypothesis by comparing a number of phase separating test conditions...
This study investigates the hydrodynamic characteristics of droplet impinging on heated surfaces using High Speed High Resolution (HSHR) imaging and evaluates the effect of surface temperature and using water and a nanofluid on a polished and a nano-structured surface. Three types of surfaces are used in the
study: polished silicon,...
The aerodynamic performance of an oscillating pitching and plunging foil operating in the energy harvesting mode is investigated. Experiments are conducted in a closed-loop recirculating wind tunnel at Reynolds numbers of 24,000 to 48,000, and reduced frequencies (k = fc/u) of 0.042 to 0.083. Foil kinematics are varied through the...
Hydrogels have been attractive for use as a medium in porous flow studies,
but have always been limited in this role because of their poor mechanical properties.
This project analyzes and tests two recently developed hydrogels,
poly(methacrylamide-co-methacrylic acid) (PMM), and a heat-treated long chain
PVA hydrogel. Particle image velocimetry (PIV)...
Oscillating foil energy harvesters are analyzed at optimal reduced frequencies (𝑘=𝑓𝑐/𝑈) to determine how the leading edge radius of curvature affects leading edge separation. The understanding of leading edge separation and its behaviors is critical to predicting the transient lift profile of an airfoil. The separation is therefore also critical...
An experimental study was undertaken to better understand the turbulent flow characteristics
within a randomly packed porous bed. A relatively low aspect ratio bed
(bed width to spherical solid phase particle diameter of 4.67) with the fluid phase
refractive index matched to that of the solid phase was used to...
An experimental study was undertaken to explore the evolution of flow structures and their characteristics within a randomly packed porous bed with particular attention to evaluating turbulent scalar dispersion. A low aspect ratio bed of 4.67 (bed width to spherical solid phase particle diameter) with fluid phase refractive index matched...
The energy harvesting performance of oscillating airfoils is studied using a discrete vortex model (DVM) with a leading-edge separation criterion. The airfoil undergoes a combined sinusoidal heaving and pitching motion at reduced frequencies of k = 0.06 − 0.16, with heaving amplitude of h0 = 0.5c, and pitching amplitude of...