摘要:

The performance of two collectors/regenerators, one glazed and the other unglazed, was studied when tested side-by-side under the meteorological conditions of Tempe, Arizona. One half of an 11 m by 11 m roof structure was covered with a series of seven Tedlar panels, each measuring 1.76 cm by 4.88 m, and the other remained unglazed. When the performance of the collector/regenerator (C/R) was expressed in terms of the quantity of water evaporated from it, which in effect was a measure of the cooling capacity of the system, the unglazed C/R performed better than the glazed C/R under the climatic conditions considered here. Nondimensional correlations for heat and mass transfer were developed from the experimental data for subsequent use with a performance model. The glazed C/R was found less sensitive to changes in independent variables and its regeneration efficiency was, on the average, 7.6% lower than the unglazed C/R. The performance of the glazed C/R approaches that of unglazed C/R at a larger height of the glazing.

ISSN:0142-5919    

DOI:10.1080/01425919208909735

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

A mathematical model of the behaviour of a fish solar dryer has been described. This model has allowed an optimization of the design of this dryer (solar-chimney area and height, insolator area, etc...). The natural convection had to pulse drying air inside apparatus, whose capacity should be 30 kg of fresh fish.

ISSN:0142-5919    

DOI:10.1080/01425919208909736

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The present paper investigates the economic viability of the solar domestic hot water systems for industrial processes in Alexandria, Egypt. Also, the optimum parameters of such systems in Alexandria, Egypt have been determined.

ISSN:0142-5919    

DOI:10.1080/01425919208909737

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

It is suggested herein to perform an analysis of the weather data prior to the transient behavior studies of the solar space cooling systems, in order to select the representative days on which system performance could be simulated. This suggestion is elaborated through an example, in which the summer days are classified into various groups based on the ambient temperature, humidity and cloudiness. The simulations of a cooling system on the representative days, selected from each group of the summer days, are presented and shown to be helpful in optimizing the system and providing an overview of the year-round system performance.

ISSN:0142-5919    

DOI:10.1080/01425919208909738

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The performance of a simple basin solar-still and a similar still coupled to an external trough type concentrator is investigated. The stills are basin-mounted inverted-V roof type, 1.67 m2area each. The assisting concentrator is a single trough-type finned tube 840 cm2receiver area with an adjustable trough half angle. The receiver tube and the basin form a thermosyphone closed loop generating a weak motion of the saline inside the stilt basin. Experiments have been conducted at Jeddah, Kingdom of Saudi Arabia ( Latitude 21°45') for an average daily solar flux 300–500 w/ m2with water levels of 5–7 cm. A single correlation to predict the stills yield is obtained on basis of data for stills of different compass orientation. The productivity of the assisted still is 22% higher than that of the simple still under the same climatic conditions. For the present results, with fixed concentrator inclination, variation of the trough half angle has no appreciable effect upon the distillation process.

ISSN:0142-5919    

DOI:10.1080/01425919208909739

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Cloud cover estimates made by trained weather observers are subjective and prone to projection and perspective errors. The paper proposes a theoretical procedure to determine the real value of the average cloud amount for a given time interval (Nreal). In case of the climate and latitudes of Romania the observed value of cloud amount (Nobs) exceeds ther real one. The results we obtained are compared with those reported by other authors.

ISSN:0142-5919    

DOI:10.1080/01425919208909740

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

This paper describes a new method of monitoring the global normal irradiance (GNI) with a completely stationary sensor. A stationary sensor comprises five individual monocrystalline Si cells mounted tangentially along a hemispherical aluminium structure. A prototype stationary GNI sensor has been constructed and a series of outdoor tests were performed. The preliminary results from several test runs show that the concept is completely feasible, and an accuracy of the GNI measurement can be within 1% of the true GNI. This sensor is particularly useful for PV test centers and demonstration plants with different PV array orientations, as well as meteorological stations without sun trackers.

ISSN:0142-5919    

DOI:10.1080/01425919208909741

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

A technical description of the large scale biotechnology facilities for biomass conversion at Soustons (Landes, France) is presented. The equipments, designed for versatility and operational flexibility, include the basic units for implementing the individual steps of lignocellulosic biomass enzymatic hydrolysis and fermentation: steam explosion pretreatment, aerobic fermentation for cellulase production, enzymatic hydrolysis, anaerobic fermentation. The main results of the large scale development of a process for production of acetone-butanol from lignocellulosic agricultural residues are presented as well as other experimentations in the field of biomass valorization. In this area the present programme is directed to conversion of lignocellulosic biomass into ethanol but the activity of the facilities also includes development work and experimental productions in a wide range of industrial fermentations.

ISSN:0142-5919    

DOI:10.1080/01425919208909742

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The following paper presents the results of a research project on the total costs to society induced by different technologies for electric power production in the Federal Republic of Germany and the conclusions of the latest international discussion on the topic. This is to say that the problem of electricity costs is looked upon from a macroeconomic perspective including the internal or private costs as well as the social costs of electricity production. The paper focuses on conventional electricity generation on the basis of fossil and nuclear fuels on the one side and on wind and photovolatic electricity as examples for renewable energy sources on the other.

ISSN:0142-5919    

DOI:10.1080/01425919208909743

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

This paper deals with the state of the art on Passive and Hybrid Cooling of buildings. The existing techniques and components to prevent thermal gains and to dissipate excess energy to environmental heat sinks are reviewed. Topics dealing with the control of internal heat gains and with the occupant activities are discussed. The state of the art on design tools is presented. Thirteen European buildings using passive and hybrid cooling techniques and components are analyzed. Finally, future research needs are discussed. This work summarizes the findings of a Horizontal study on Passive Cooling carried out by the authors (1), as part of the Building 2000 research program of the European Communities.

ISSN:0142-5919    

DOI:10.1080/01425919208909744

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor