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Microencapsulated phase change material (MPCM) slurries were field-tested in ground source heat pump (GSHP) systems in the Southern United States to validate their thermal performance and durability as heat transfer fluids (HTF). MPCM particles consisted of methyl stearate (melting temperature: 39.5 ˚C) as phase change material (PCM), microencapsulated with polyurea shell. Experimental results showed that MPCM slurries transport more thermal energy than water at a constant pumping power due to the higher heat capacity associated with the PCM. Demonstration experiments showed that using MPCM slurries improved the heat load-to-pumping power ratio by up to 34 % when using a coaxial heat exchanger. The coefficient of performance of the GSHP system was enhanced by up to 4.9 % when using MPCM slurries. It can be concluded that MPCM slurries are viable HTF because of their higher heat capacity. In terms of durability, no

Preparation of nanomaterial dispersion or nanofluids requires good characterization techniques, including particle size and morphological measurements. A reliable and straight-forward process to characterize and quantify the degree of dispersion and agglomeration is needed. A wet-cell transmission electron microscope (TEM) technique has been developed to make comparisons between sonicated and hand-shaken solutions of both aluminum oxide nanoparticles and multi-walled carbon nanotubes. In each case, the wet-cell TEM technique reveals images of nanoparticles well dispersed in aqueous solutions due in part to the use of ultrasonic power instead of simply manual shaking and stirring. The technique is currently qualitative and shows great potential for a host of nanotechnology applications.

Electroosmotic water vapor transport (WVT) across very thin, flexible, functionalized conducting polymer (CP) microporous (μP) membranes at a very high rate is reported. Both passive and active (6 VDC applied) WVT are reported, the latter for the first time ever. WVT occurs with concomitant, effective blocking of chemical warfare (CW) agents, again demonstrated for the first time ever. Initial active liquid||membrane||liquid interface studies demonstrated WVT rates of >1.7 × 10^-5g ^.mm^-2s^-1, >3 × the highest prior reported values of 5 × 10^-6g.mm^-2s^-1. Subsequent vapor||membrane|| vapor interface studies using industry-standard methods (including ASTM E96B Upright Cup (“WVT”), ASTM F2298 (“Dynamic Moisture Permeation Cell”) and ASTM F1868 (“Sweating Guard Hotplate”) were done at independent, external labs for independent corroboration. These yielded, e.g., WVT values of2564.4 g.m².d^-1 (passive) and3706.7 g.m²d^-1 (active), to be compared with the highest (passive) value ever reported previously,984.8 g.m².d^-1 for a μP-Nylon membrane. More than 15 different membrane configurations, porosities and types were studied, including membranes with CP + organophosphate hydrolase (OPH), an enzyme reactive to CW agents. Efficient blocking of the actual CW agents GB, HD, VX is also reported, using the TOP-8-2-501standard. Membranes also passed all Industry-standard durability tests, e.g. ASTM D2261 (Tearing), ASTM D5034 (Breaking), ASTM D3886 (Abrasion), ASTM F392 (Gelbo Flex). Inco...

U. S. Army Corps of Engineers Engineer Research and Development Center, Construction Engineering Research Laboratory (ERDC-CERL), and Carlyle Consulting’s John Carlyle conducted a leak detection survey at a U.S. Army Installation. The age of pipes in the distribution system ranged from 20 to 60 years. The thrust of the work was to acoustically survey all of the underground pipelines constituting the installation’s potable water distribution system and find any leaks. The results of the survey were that 6 leaks were discovered in the main lines, 63 leaks associated with fire hydrants, freeze proof hose bibs, water meters, etc., and 33 leaks inside buildings. Over two thousand acoustic measurements were made in order to obtain these results.