Lead zirconate titanate (PZT) is the dominant ferroelectric material in the market due to its excellent piezoelectric properties, relatively high Curie transition temperature (T[subscript C]), low cost, etc. However, because of emerging applications with requirements for high temperature (T[subscript C] > 400 °C) ferroelectrics, researchers are increasingly looking at alternative...
New alloys containing refractory metals have been developed
by the aero-space industry to meet the demand for thermally resistant
materials. The chemical analysis of these alloys has been
handled successfully by the use of ion exchange. Hydrofluoric acid,
either alone or combined with hydrochloric acid, has here-to-fore
been used to...
Electric power needs will only grow over the next decades as more humans ascend from poverty into the middle class. Currently, the majority of electric power is generated by burning fossil fuels. To help mitigate the undesirable effects of burning fossil fuels research is being done to increase the efficiency...
Various antifoulant treatment programs and the
considerations necessary for the effective use of such
programs were examined.
Two different groups of tests, with and without
iron contamination, have been carried out on the
effectiveness of several of the state-of-the-art
copolymers (PA, HEDP, AA/HPA, AA/MA, SS/MA and AA/SA) in
the inhibition...
The fouling characteristics of cooling tower water
containing various corrosion inhibitors and other additives
on heat transfer surface have been investigated. Corrosion
inhibitors investigated included zinc-chromate and
phosphates. In addition, additives including polyacrylate
and phosphonate (HEDP and AMP) were used to determine their
effectiveness as antifoulants.
The tests were conducted...
CPM-M4 tool steel is a commonly used knife blade material due to its high strength and wear resistance. The goal of this thesis is to understand how heat treatment parameters affect blade performance and microstructure.Five heat treatments were applied to CPM-M4 steel by varying austenitizing and tempering temperatures. The microstructures...
To improve energy efficiency of industrial processes, heat exchangers are used to transfer thermal energy between different process streams. The compact size and increased efficiency of microchannel based recuperators make them appealing in extreme environments where costly superalloys are mandatory. Due to the high manufacturing cost of microchannel heat exchanges...
To improve the performance of solid oxide fuel cells, a secondary power cycle can be driven by the recuperation of exhaust gas heat. Microchannel recuperators are attractive for waste heat recuperation due to compact form factors which also minimize the mass of the expensive superalloys required. This paper introduces 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...