In terms of performance, natural cooling technologies have always been studied by experimentation of single techniques. In order to obtain an improvement in global performance, particularly with ...regard to comfort, an investigation of the combined utilization of several techniques for the same location has been carried out. This paper gives the results of a series of experiments in which several techniques of natural cooling were applied simultaneously in an experimental building.
The usefulness of defining the cooling potential and other related variables is a function of how these figures will help the designer in the decision taking process. Consequently, a rational ...approach to these definitions should start from a certain design methodology
The present paper proposes a design methodology which uses the concepts of gross cooling potential, net cooling potential, available cooling potential, usable cooling potential and natural cooling saving fraction. These concepts are expressed under common terms for three natural cooling techniques (NCT), radiative cooling via night sky radiators, ground cooling using buried ducts and evaporative cooling via mechanical evaporative coolers.
The objective is to develop a systematic procedure of producing information about the suitability of using a certain NCT in a given locality and for a certain building. The application of the methodology mentioned for a set of European localities has been included in the ATLAS about the potential of NCT which constitutes one of the final products of the PASCOOL project.
Droplet Solidification of GaSb Takada, Yukinobu; Kudoh, Masayuki
Journal of the Japan Institute of Metals and Materials,
01/2002, Volume:
66, Issue:
10
Journal Article
Peer reviewed
Open access
A new experimental setup was constructed to make one suspending droplet. This method was named as “the suspended droplet method”. Some fundamental findings on the droplet solidification of pure Al ...and Al alloys were obtained by the method. In this study, solidification behavior of a suspending droplet in Ga-50 at%Sb, Ga-40 at%Sb and Ga-60 at%Sb alloys is investigated. A droplet with approximately 1 mm and 2 mm in diameters is solidified with naturally or forcedly cooled conditions. Also it is forcedly cooled under micro-gravity atmosphere. In the naturally cooled solidification, all specimens with 1 mm and 2 mm in diameters have indefinite shape with a projection except for the specimen with 2 mm in diameter of a Ga-60 at%Sb alloy. The solidified microstructure of a Ga-50 at%Sb alloy might be composed of one dendrite. On the other hand, forcedly cooled specimens have a shape like sphere and their grain sizes become large when the specimen is 1 mm in diameter or solidifies under micro-gravity even though it is 2 mm in diameter.
The design and performance of an ancient passively cooled mahal (building) have been presented. The mahal was generally used for pilgrims during their visit to the city of Banaras. Energy balance ...equations for different components, namely walls and roof, of a mahal have been used to evaluate the performance of the mahal in terms of an enclosed-room air temperature. It is observed that a reasonable thermal comfort temperature is achieved by ventilation using natural cold air through the windows.
Provider: - Institution: - Data provided by Europeana Collections- PHDC, es un proyecto internacional, creado con el objetivo de promover el uso de sistemas de refrigeración Pasivos e Híbridos en los ...edificios entre profesionales de diseño, constructores, propietarios y usuarios. En este artículo, se describen brevemente algunos de los sistemas PHDC. En el marco de este proyecto, el trabajo de investigación realizado produce dos herramientas informáticas para el mejor y máximo aprovechamiento del objetivo del proyecto, las cuales se presentan en este artículo. Las herramientas comentadas son dos: – PHDC AirFlow, en la que se implementa el “método del bucle de presiones” para el cálculo de los caudales de aire que circulan por el interior del edificio. Se analizan los elementos-sistemas-características del edificio, con objeto de integrar un sistema de climatización basado en enfriamiento evaporativo, y se le ofrece al usuario la posibilidad de modificarlos, además se destaca la capacidad de integrar captadores de viento, chimenea solar, sistema de enfriamiento evaporativo basados en medio poroso, micronizadores o pulverizadores. – Y PHDC Energy & Comfort, en la cual se simula el comportamiento térmico del edificio: cargas térmicas, consumos del sistema de refrigeración convencional y ahorro producido al integrar el sistema evaporativo elegido en la herramienta anterior.- PHDC is an international project with the objective of promoting use of passive and hybrid cooling systems in buildings between design professionals, builders, owners and users. This article describes some of the systems PHDC analized. Under this project, work of the authors produces two tools for improving and optimization of the objective of project, which are presented in this article. The tools discussed are two: – PHDC AirFlow, which implements the «loop pressure method» for calculating the air flow inside the building. It discusses elements, systems and building characteristics, in order to integrate an air conditioning system based on evaporative cooling, and offers capacity to modify, also user can integrate sensors wind, solar chimney, system based evaporative cooling in porous media, micronisers or sprays. – And PHDC Energy & Comfort, which simulates thermal behavior of building: thermal loads, consumption of conventional cooling system and savings produced by integrating the evaporative system chosen in the previous tool.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
A simplified approach to thermal building behaviour using natural cooling techniques has been proposed within the frame of the
Pascool/Joule II European project. This provides useful information ...relating to the feasibility of integration of natural cooling techniques into a given building, taking into account only the climatic potential of the site, the indoor comfort criteria and the building cooling requirements. This approach is useful for architects and building designers, offering them helpful tools for the selection stage of the cooling system types. However, it is insufficient for the building design stage, where more accurate results, dealing with thermal behaviour and energy consumption of the building, are required. In order to solve this, we propose a thermal evaluation approach to building using direct and indirect evaporative cooling systems. This work has been realized using the integration of the passive cooling system models developed by our team in
Passport+, a thermal building software, developed in the European projects
Pascool/Joulell and
Altener/Sink. This approach has been applied to a typical office building in La Rochelle (France). This procedure offers useful informations relating to the building behaviour (thermal and comfort behaviour), defines the cooling installation by sizing the passive and/or conventional cooling systems and shows the building energy saving by both the direct and indirect evaporative cooling system.
Une approche simplifiée du comportement des systèmes de rafraîchissement naturel des bâtiments a été proposée à l'issue du projet européen
Pascool/Joule II. Elle permet de fournir des informations relatives à la faisabilité de l'intégration d'une technique naturelle de rafraîchissement à un bâtiment donné, en ne considérant que le potentiel climatique du site et les exigences liées au confort des occupants. Cette approche est utile aux architectes et aux concepteurs de bâtiments, dans la mesure où elle leurs procure des outils d'aide à la décision lors de la phase d'avant-projet. Cependant, elle s'avère insuffisante lors de la phase de conception, au cours de laquelle on a besoin d'une plus grande précision sur le comportement énergétique du bâtiment, en particulier pour le dimensionnement des systèmes. Pour remédier à cette insuffisance, nous proposons dans cet article une méthode d'évaluation thermique des bâtiments munis de systèmes de rafraîchissement adiabatique direct et indirect. Ce travail a été réalisé par intégration des modèles de comportement de ces systèmes de rafraîchissement passifs, dans le code de thermique du bâtiment
Passport+ développé par notre équipe dans le cadre des projets européens
Pascool/Joule II et
Altener/Sink. Cette procédure d'évaluation, appliquée sur un bâtiment tertiaire type situéà La Rochelle, fournit des informations utiles quant au comportement du bâtiment (du point de vue de la thermique et de la qualité de l'air), permet le dimensionnement des systèmes de rafraîchissement passif et/ou actif et montre l'intérêt économique de recourir à des techniques passives (adiabatiques) pour rafraîchir les bâtiments.
PDF
