A boron-modified molybdenum silicide material having the composition comprising about 80 to about 90 weight % Mo, about 10 to about 20 weight % Si, and about 0.1 to about 2 weight % B and a multiphase microstructure including Mo.sub.5 Si.sub.3 phase as at least one microstructural component effective to impart good high temperature creep resistance. The boron-modified molybdenum silicide materi...

Air flow through electric fan heater channel is governed by coupled, non-linear partial differential equations; these equations have to be solved within on irregular domain subject to various initial and boundary conditions. Computational Fluid Dynamics (CFD) replaces fluid flow equations by a set of algebraic equations, these algebraic equations can be solved using digital computers. Wall to a...

This paper assesses the role of heating entitlements in generating stark air quality differences across China. During the 1950-1980 central planning period, the Chinese government established free winter heating of homes and offices as a basic right via the provision of free coal fuel for boilers. The combustion of coal in boilers is associated with the release of air pollutants, especially tot...

his investigation was carried out to reveal the impact of solar radiation on wind flow structure and pollutant dispersion in an urban street canyon of aspect ratio of one using the computational fluid dynamic (cfd) technique. the simulation results (velocity and concentration data) show that heating from building wall surfaces and ground lead to strong buoyancy forces as the air is heated by th...

in this study, a numerical simulation using the cfd software, fluent, has been conducted to examine the effect of various shapes of the venturi component sections in order to find the optimum venturi specifications to increase the egr rate with minimum pressure loss at the part load operation range. the cfd results reveal that the venturi should be precisely optimized to introduce the required ...

ABSTRACT Most office buildings in Germany have either no mechanical ventilation system or a centralized ventilation system with fresh and exhaust air supply. Within the last 10 years some projects using decentralized ventilation systems (DVS) came up. Common for this type of decentralised systems is that they take fresh air directly from outside through the facade via the DVS into the room. Wit...

In our daily life, central heating systems are generally used in home and office heating. The majority of fuel used in these systems are either natural gas or coal. However, in some cases air-conditioners and electrical oil-radiators are preferred in the heating of small mediums. But, the cost of electrical based heating is much higher than the cost of natural gas or coal based heating. Conside...

A 2715 ft2 (252 m2), two story, residential home of the style typical of the Gaithersburg, Maryland area was constructed in 2012 to demonstrate technologies for net-zero energy (NZE) homes (or ZEH). The NIST Net-Zero Energy Residential Test Facility (NZERTF) functions as a laboratory to support the development and adoption of cost-effective NZE designs, technologies, construction methods, and b...

The Power Systems Development Facility (PSDF) is an engineering scale demonstration of advanced coal based power systems, including the KBR Transport Gasifier, a hightemperature, high-pressure syngas filtration system, and a gas cleanup unit. Designed to be at a sufficient scale to test advanced power systems and components in an integrated fashion, the PSDF provides data necessary for commerci...

In recent years, China has experienced severe air pollution with adverse health consequences, as exemplified by recent reports of extremely high PM2.5 levels in northern cities such as Beijing. PM2.5 sample measurements have identified coal burning as a significant primary pollutant source in China, especially when coal is used as a major heating fuel in the winter. As urbanization and househol...