The thermal wave technique has been explored for the use of liquid thermal conductivity measurement and flow property diagnostics in this dissertation. For liquid thermal conductivity measurements, an experimental technique based on the thermal wave approach is developed. A stainless steel strip functions as both a heating element and a...
Droplet and spray impingement cooling are typically used in high heat flux
thermal management. In this thesis, droplet impingement and evaporation heat transfer
characteristics are determined from measured spatially- and temporally- varying fluid
and surface temperatures. Unique to this study is the documentation of the effects of
using a nanofluid...
This thesis presents a feasibility study of a means to passively effect liquid motion parallel to a heated surface though surface geometrical modifications. Such a passive system is beneficial for electronics cooling applications as it reduces the pumping equipment normally required in flow loops and is desired for space applications,...
Advances in electronics fabrication, coupled with the demand for increased computing power, have driven the demand for innovative cooling solutions to dissipate waste heat generated by these devices. To meet future demands, research and development has focused on robust and stable two-phase heat transfer devices. A confined impinging jet is...
A unique channel surface enhancement technique via diffusion-bonding a layer of conductive fine wire mesh onto the heating wall was developed and used to experimentally study flow boiling enhancement in parallel microchannels. Each channel was 1000 μm wide and 510 μm high. A dielectric working fluid, HFE 7000, was used...
The effect of a non-uniform magnetic field on the coupled transport of momentum and heat is studied for the case of laminar pipe flow of a magnetically susceptible ferrofluid. The momentum and heat transport equations are complemented with the necessary electromagnetic terms and used to develop a computer simulation of...
A miniature reciprocating expander is being developed as part of a larger program to develop a heat actuated heat pump for portable applications. By utilizing the higher energy density of liquid hydrocarbon fuels relative to batteries, a heat actuated heat pump would be able to provide cooling for much longer...
Natural convection provides a means for circulating fluids without the use of pumps. This type of system is of great interest for a wide variety of applications, including solar heaters, process industry, and nuclear reactors. Natural convection will play a vital role in the area of passive safety and reliability,...
The present study proposes to investigate the flow structure of different arrays of jets impinging on a flat surface enclosed by three walls, creating a channel that forces the air to leave in one preferential direction, generating a self sustain crossflow. Details of both the mean and some turbulence quantities...
The effects of the orifice geometry and the surface boundary condition on the heat transfer distribution to a flat surface of an impinging jet array were investigated. The jet array impinged normally onto the surface which was either isothermal or had a uniform heat flux. The experiments were performed for...
Heat transfer and fluid mechanical behavior of water
flowing horizontally in vertically-narrow rectangular
channels was studied in this work. Friction factor and
Nusselt number variations were determined experimentally
for four different wall heating conditions, and for aspect
ratios(height to width) of 5, 4, 3, 2, and 1. Wall
heating conditions...
Miniature energy and chemical systems (MECS) are miniature thermal, fluid, and chemical devices in the mesoscale size range between a sugar cube and a human fist. MECS take advantage of improved rates of mass and heat transfer that have been observed at the microscale. There are many potential applications for...
Described in this thesis is an investigation of the fully developed natural convection
heat transfer in a vertical channel formed by two infinitely wide parallel plates
maintained at a uniform wall temperature. Closed-form solutions for the velocity
and temperature profiles are developed along with local and averaged Nusselt
numbers. The...
Production of surimi represents a potential utilization of a number of low-valued
fish species, one of which, Pacific whiting, represents the largest biomass off the West
Coast of the United States. However, a protease enzyme softens the fish flesh in Pacific
whiting and limits the expansion of surimi production.
Many...
The problem of heat transfer due to free convection in a channel formed
by two parallel, isoflux, vertical plates is of considerable importance in electronic
cooling applications, thermosiphons, the optimum spacing of plates or components,
industrial stacks, heat exchangers, nuclear power plants and combustion involving
vertical walls. Although in each...
Characterization of local boiling trends, in addition to the typically reported area-averaged trends, is essential for the robust design and implementation of phase change technologies to sensitive heat transfer applications such as electronics cooling. Obtaining the values of heat fluxes corresponding to locally varying surface temperatures has been a challenge...
