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Introduction
Published in John Roberts, Alan Tovey, Anton Fried, Concrete Masonry Designer's Handbook, 2014
John Roberts, Alan Tovey, Anton Fried
In practice, the present levels of workmanship on site to indicate the potential leakage of streams of water mean that particular care needs to be taken in the through the wall, in conditions of sustained driving selection of components. The following factors should be rainfall. The method determines the in-situ measurement taken into account: of the air permeance of walls on site. This makes use of a vacuum box and guard arrangement, which are held on the wall by excess atmospheric pressure. A dry seal is provided by flexible plastic foam. Measurements have been made on the outer leaves of over 80 houses with cavity walls. These had mean air permeances between 100 and 6501.m-2min-1 at 150mm WG pressure. This implies that in rain storms unrendered outer can be expected to allow considerable volumes of water to enter the cavity. The air permeance equipment has also proved useful, for the preliminary assessment of walls to be used in wetting tests both for full-scale tests on houses and for small-scale tests on wallettes.
Drilling in the Permafrost with Chilled-Air Scavenging
Published in B.B. Kudryashov, A.M. Yakovlev, Drilling in the Permafrost, 1991
B.B. Kudryashov, A.M. Yakovlev
Both in drilling practice and commercial exploitation of wells, the use of tubes coated on the inside is quite well known. Tubes coated on the inside are also manufactured by the tubes industry to prevent corrosion, reduce hydraulic losses by providing a paraffin coating which glazes the surface to reduce the surface roughness and other purposes. The materials which are presently used or could be used to coat the tubes are: glass-enamel, organosilicates, epoxy resins, polyethylene, polyvinylchloride plastic, high density polystyrene, phenolic plastic foam, polyurethane foam and many other synthetic materials. In the USA teflon and teflon-glass are also used as coating materials among many others.
Acoustics and acoustic devices
Published in Michael Talbot-Smith, Audio Engineer's Reference Book, 2013
Bob Walker, Talbot-Smith Michael, Chris Woolf, John Borwick, Francis Rumsey, John L. Andrews, Peter Baxandall, Alan Tutton
important. Reference microphones in wind-tunnels often use carefully shaped nose-cones but since real wind is chaotic and unpredictable in direction simpler spheres or round-ended cylinders are the norm. The metal mesh grilles of most microphones owe more to strength than to aerodynamic refinement but the addition of a cover that can slow the wind-speed and reduce its turbulence is quite simple. The other requirements of this cover are that it should not be able to generate any noise itself and that it should be transparent to low-particle velocity audio waves. One such material is open-cell plastic foam.
Homogeneous-heterogeneous chemical reactions and effectiveness of thermo-sloutal time’s relaxation concept in Carreau fluid flow
Published in Waves in Random and Complex Media, 2022
Various materials for industrial use, such as suspensions, emulsion, foam, construction of power stations, plastic foam filtering, bubble absorption, printing inkjet, mayonnaise manufacture, and polymer smelting, are not subject to Newton’s law of viscosity. All these materials indicate the relation between shear stress and the rate of shear. Many rheological models accurately elaborate on the behavior of the material. Lodgès molecular network theory has been quite successful in describing the linear viscoelastic behavior of polymer solutions and melts, but it has failed to explain the dependence of strain rate on various material functions discussed by Carreau [1]. Carreau extended his work on a linear relationship that between the logarithm of the zero-shear viscosity and the polymer concentration [2]. The generalized Carreau fluid in a two-phase model with a magnetic field and nanoparticles was studied by Eid et al. [3]. The study related to natural convection in a Carreau nano-fluid by an optimal homotopy analysis method is debated in [4]. Further relevant literature is found in Refs. [5–9].
Exploring the dynamics of natural convective Prandtl fluid flow subjected to induced magnetic field
Published in Waves in Random and Complex Media, 2022
E. Azhar, A. Kamran, S. M. Atif
Several citing of problems in the fluid dynamics related to heat transfer can be seen in literature where the working fluid shows nonlinear relation between stress and strain. Such fluids are named non-Newtonian fluids which can be found in bubble formation, in polymer and plastic foam manufacturing procedures. The mathematical correlation in such fluids is a complex one, deviating from the Newtonian law of viscosity and numerical handling thus becomes a difficult task. The situation turns out to be more challenging if magnetic field effects are considered. Many investigations are found in literature where complex non-Newtonian magnetohydrodynamical systems have been handled numerically. Atif et al. [19] tackled a problem of micropolar nanofluid flow over a stretching surface using the shooting technique. They used the non-Fourier and Fick's laws instead of the conventional definitions. Flow was subjected to MHD and solved numerically by the shooting technique. Kamran et al. [20] threw light on a Casson nanofluid model influenced by MHD over a plane surface stretched in the forward direction using the Keller box method. They found that the velocity of fluid diminished with strengthening of the magnetic field. Similar instances can be found in [21, 22].
Characterization of refuse derived fuel samples prepared from municipal solid waste in Vellore, India
Published in Environmental Technology, 2022
Bonny Thawani, Biswanath Mahanty, Shishir Kumar Behera
The materials considered for RDF samples were plastic, thermocol, foam and jute straw. Rubber and textile were not considered because of their potential to be recycled and low heating value, respectively [3]. Four samples of RDF with different compositions were chosen (referred to as RDF-A, RDF-B, RDF-C, RDF-D) in this study as shown in Table 2. RDF-A was prepared to mimic the composition of waste available in the MCCs, and the remaining samples were prepared to keep one component in excess proportion, each at a time, in order to measure the change in fuel performance. As the plastic in MSW could be partially recycled, the RDF blend containing higher as well as lower proportion of plastic than the reference MSW blend has been included. The sum of non-biodegradable components (foam, plastic, thermocol) in blend B, C and D remained constant while enriching it with one component at a time. For example, compositions in B, C and D were enriched with plastic, foam and thermocol, respectively.