Emittance
Mostrando 1-12 de 13 artigos, teses e dissertações.
-
1. Selective Solar Surface Solar Based on Black Chromium: Influence of Electrodeposition Parameters in the Absorption of Surfaces
The search for the reduction of costs for the implementation of renewable energies implies in the optimization of the parameters of the manufacturing processes of consolidated technologies. Among these technologies are the solar collectors composed of absorber films characterized by high absorption in the spectrum range corresponding to solar radiation and l
Mat. Res.. Publicado em: 25/02/2019
-
2. Development of paints with infrared radiation reflective properties
Abstract Large buildings situated in hot regions of the Globe need to be agreeable to their residents. Air conditioning is extensively used to make these buildings comfortable, with consequent energy consumption. Absorption of solar visible and infrared radiations are responsible for heating objects on the surface of the Earth, including hou
Polímeros. Publicado em: 2015-06
-
3. Produção de Superfícies Seletivas de Ni/NiO para Aplicações em Coletores Solares / Produção de Superfícies Seletivas de Ni/NiO para Aplicações em Coletores Solares
Novas tecnologias e novos materiais vêm sendo desenvolvidos a fim de tornar a tecnologia solar economicamente mais atrativa. Materiais como o níquel (Ni) e o óxido de níquel (NiO) depositados sobre alumínio têm-se destacado em várias aplicações fototérmicas atuando como superfícies seletivas para a faixa do espectro solar. As superfícies seletiva
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 08/08/2011
-
4. Analytical method for determining at equilibrium the envelope and emittance of initially mismatched beams
This work presents a fully analytic way of determining relevant equilibrium quantities of a high-intensity charged particle beam submitted to magnetic focusing while inside a linear channel. Through the current approach, some intermediate steps of our original hybrid model which had to be solved numerically can now be eliminated, leading to the obtainment of
Publicado em: 2011
-
5. New concept of space radiator with variable emittance
A new concept of space radiator of variable emittance for satellite thermal control is presented. The radiator is composed of two stages which exchange heat through radiation between finned surfaces covered with variable emittance coatings, whose emissivity is increased with temperature. Under cold conditions the radiative heat coupling between the stages is
Journal of the Brazilian Society of Mechanical Sciences and Engineering. Publicado em: 2010-12
-
6. Simulation studies for ion beam extraction systems
The characteristics of the ion beam extracted from an ion sources were investigated using computer code SIMION 3 D Version 7.0. It has been used to evaluate the extraction system in order to produce an ion beam with high current and low beam emittance. The results show that the shape of the extraction electrode plays an important role in ion beam formation.
Brazilian Journal of Physics. Publicado em: 2009-06
-
7. Simulation of the plasma meniscus with and without space charge using triode extraction system
In this work, simulation of the singly charged argon ion trajectories for a variable plasma meniscus is studied with and without space charge for the triode extraction system by using SIMION 3D (Simulation of Ion Optics in Three Dimensions) version 7 personal computer program. The influence of acceleration voltage applied to the acceleration electrode of the
Brazilian Journal of Physics. Publicado em: 2009-03
-
8. Desenvolvimento de um equipamento para medição de emissividade / Development of an equipament to emissivity measurement
Este trabalho apresenta a metodologia empregada para desenvolvimento e utilização de um equipamento para medir valores de emissividade hemisférica. O referido equipamento permite efetuar simultaneamente medidas de emissividade através do método calorimétrico e do método radiométrico. O calorímetro mede o fluxo de calor entre duas superfícies parale
Publicado em: 2009
-
9. Commissioning of the injector system of the IFUSP Microtron / "Início de operação e caracterização do sistema injetor do Mícrotron do IFUSP"
In this work we present the commissioning of the IFUSP Microtron injector system. We developed a new method to treat misalignments on a single lens as well as in a group of them. We installed an image acquisition system to acquire beam images from the fluorescent screen monitor. Emittance was measured and found to be (2,32 ± 0,05) pi.mm.mrad, independently
Publicado em: 2006
-
10. Estudo Comparativo de SuperfÃcies Seletivas para Coletores Solares / Comparative Study of Selective Surfaces for Solar Collectors
In practical applications of active and passive solar energy, or other construction purposes, the coating material which absorbs solar radiation has an important role as regards the absorption and emission of thermal radiation and, directly influencing the cost benefit the product. Surface coatings for solar radiation-absorbing plate or selective surfaces, c
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 07/12/2001
-
11. Numerical and experimental investigation of thermal louvers for space applications
Thermal louvers, using movable or rotating shutters over a radiating surface, have gained a wide acceptance as highly efficient devices for controlling the temperature of a spacecraft. This paper presents a detailed analysis of the performance of a rectangular thermal louver with movable blades. The radiative capacity of the louver, determined by its effecti
Journal of the Brazilian Society of Mechanical Sciences. Publicado em: 2001
-
12. Tranferencia de calor no escoamento de gases participantes em alta temperatura atraves de dutos de secção circular revestidos com isolamento não ideal
In this Master degree thesis, the heat transfer in the flow of participating gases through circular cross section ducts is studied, combining the three basic processes: conduction, convection and radiation. It is considered the case in which a high temperature gas tlows through a tube covered by a non-ideal insulation. The gas inlet temperature is uniform an
Publicado em: 1995