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Engineering topics

Lewis, D. H.

Publications and source records attributed to Lewis, D. H..

Reduced viscosity interpreted for fluid/gas mixtures

Analysis predicts decrease in fluid viscosity by comparing pressure profile of fluid/gas mixture with that of power-law fluid. Fluid is taken to be viscous, non-Newtonian, and incompressible; the gas to be ideal; the flow to be inertia-free, isothermal, and one dimensional. Analysis assists in design of flow systems for petroleum, coal, polymers, and other materials.

Lewis, D. H.↗

Two-stage combustion for reducing pollutant emissions from gas turbine combustors

Combustion and emission results are presented for a premix combustor fueled with admixtures of JP5 with neat H2 and of JP5 with simulated partial-oxidation product gas. The combustor was operated with inlet-air state conditions typical of cruise power for high performance aviation engines. Ultralow NOx, CO and HC emissions and extended lean burning limits were achieved simultaneously. Laboratory scale studies of the non-catalyzed rich-burning characteristics of several paraffin-series hydrocarbon fuels and of JP5 showed sooting limits at equivalence ratios of about 2.0 and that in order to achieve very rich sootless burning it is necessary to premix the reactants thoroughly and to use high levels of air preheat. The application of two-stage combustion for the reduction of fuel NOx was reviewed. An experimental combustor designed and constructed for two-stage combustion experiments is described.

Clayton, R. M.↗

4-ferrocenyl-1,3-pentadiene.

A convenient route is reported to a synthesis of 4-ferrocenyl-1,3-pentadiene which makes use of the well known Wittig (1954) reaction. The starting materials, acetylferrocene and allyltriphenylphosphonium bromide, are readily available, and the experimental conditions have been optimized so as to allow the synthesis to be carried out on a molar scale without the occurrence of extensive polymerization.

Lewis, D. H.↗