ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1991.01-13.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

AbstractThe Zolder case was one of the six case studies on mould problems and sulface condensation, initiated within the International Energy Agency (IEA) Annex 14 on “Condensation and Energy”. This project, a joint research effort of Belgium, the Federal Republic of Germany, Italy, the Netherlands and the United Kingdom, was completed in March 1990.Complex relations bemeen mould, surface condensation, energy caservation and parameters such as the outdoor climate, the thermal quality of the building, the ventilation and the occupants' behaviour are explained, followed by an analysis of the Zolder‐Lindeman case. This illustrates the extent to which mould may deteriorate the livability of a social housing estate. On three houses, different mitigation measures were evaluated before and after implementation: loft space insulation, inside insulation, double glazing outside insulation, natural ventilation, and demand controlled ventilation.The results for one of the three show that the severe mould problems resulted from the cambination of poor overall insulation quality and the impossibility of ventilating properly. A thermal retrofit, together with the installation of a natural ventilation system, proved to be succe

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1991.02-13.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

AbstractMechanical ventalation system performance involves the provision of adequate amuunts of outdoor air, uniform distribution of ventilation air within the occupied space, and the maintenance of thermal comfort. Standard measurement techniques exist to evaluate thermal comfort and air change rates in mechanically ventilated buildings; procedures to evaluate air distribution or ventilation effectiveness in the field are still being developed. This paper presents measuremetlts of air change rates and ventilation effectivenes in an office/library building in Washington, DC. The tracer gas decay technique was used to measure whole building air change rates. The air change rates during the measurement period were essentially constant at about 0.8 air changes per hour, somewhat below the design specification and above the minimum recmmmded in ASHRAE Standard 62‐1989. Ventilation effectiveness was investigated at several locations within the building through the measurement of local tracer gas decay rate and mean local age of air. The ventilation effectiveness measurements serve as an investigation of the applicability of the m e a s u r r n procedures employed, providing insight into the measurement issue of establishing initial conditions, the spatial variation in test results within a building, and the repeatabildy between tests. The results of the ventilation effectiveness meusurements are consistent with good distrhtion of the outdoor air by the ventilation system and good mixing within the occupied spac

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1991.03-13.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

AbstractWe studied the performance of a task ventilation system that permits occupants to control the flow rate and direction of air supplied to their work space through four floor‐mounted supply grill. Air exited the room through a ceding‐mounted return grill. To study air‐flow patterns, we measured the age of air at multiple locations using a tracer gas stepup. To study the intra‐room transport of tobacco smoke particles, cigarettes were smoked mechanically in one workstation and particle concentrations were measured at multiple locations. Our major findings were as follows: (1) deviations from uniform age of air, and uniform particle concentration, were generally less than 30 percent; (2)some supply air short‐circuits to the return grill when directed toward the return with high velocity; (3) low supply velocities resulted in a floor‐to‐ceiling displacement flow; (4) directing the supply air toward the occupant, of partially toward the occupant, typically yielded an age of air at the occupant's breathing level that was 15 to 25 percent lower than the age at other breathing‐level locations; (5) with low supply velocities und air directed toward the occupants, tobacco smoke particle concentrations in a ventilated non‐smoking workstation were 50 percent of the chamber‐av

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1991.04-13.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

AbstractThis paper describes tests of thermal comfort and air distribution performance of two relatively new occupant‐controlled localized ventilation (also called task ventilation) systems. The first is a raisd‐floor distribution system providing air through grilles in the floor panels, and the second is a desk‐mounted unit supplying conditioned air at desktop level. The tests were performed in a new controlled environment chamber (CEC) having unique capabilities for detailed studies of space conditioning and thermal comfort in office environments. Measurements were made in a mockup of a typical partitioned open‐plan office, and the resulting temperature and air velocity distributions are reported for a variety of system‐ and locally controlled conditions. Comfort model predictions are presented to describe the degree of environmental control and range of occupant comfort levels produced in the workstations. The results are also compared to those produced by a conventional ceiling supply system.The tests investigated the effects of supply volume, supply location, supply vent orientation, supply/return temperature difference, heat load density, and workstation size and layout. Temperature differences in the range of 1–2.5°C were observed between adjacent workstations, and local air velocities in the vicinity of outlets could exceed 3 m/s. Such wide‐ranging values could violate existing comfort standards (ASHRAE, 1981; ISO, 1984), if strictly interpreted. However since these systems put the local thermal conditions within the workstations under the direct control of their occupants, it is recommended that the standards grant exceptions t

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1991.05-13.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

AbstractThis paper describes the techniques used within the ESPR3system to represent and solve the heat and mass conservation equations relation to combined building and plant systems. In Particular, it describes the equation‐sets used to represent inter‐zonal (building) and inter‐component (plant) fluid flow and the method used for the integration of the non‐linear heat and muss frow equations. By means of a case study, the application in a real design context is demon

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1991.06-13.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

AbstractThis paper discusses three methods for measuring inter‐zonal air movements in two‐zone buildings: initial injection of one tracer into a single room, repeated injection of one tracer into two rooms, and initial injection of two tracers into two rooms. The description of these methods includes an outline of the theoretical background, the presentation of suitable injection strategies and algorithms for the evaluation of the concentration profiles. A detailed error analysis using Monte‐Carlo‐simulation shows the precision of these methods for a variety of cases, such as different magnitudes of the inter‐zonal airflows and various measurement

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1991.07-13.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

AbstractThe main airflow and contaminant paths or the spatial distribution of the age of air (or contaminant) in a room are of great interest in estimating venrilation efficiency. A simple meusurement method is presented which consists of injecting one or more tracer gases at locations of interest and analysing the concentration at several other locations, carefully chosen for best accuracy.Response functions can be fitted to these measurements, which are the age of the tracers or of the air or the concentration of the tracers as a function of the location. The salient paths, such as the dead zones, are also determined from these functions.The paper presents the method, its application and validation in a well controlled test room.

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1991.08-13.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

AbstractA new turbinemeter has been developed to be used as a ventilation rate sensor in livestock buildings. On the basis of a previous sensor introduced in 1983, several improvements have been made to develop a low‐cost airflow rate sensor with an acceptable accuracy of 60 m3/h in a range from 200 to 5000 m3/h for pressure differences from 0 to 120 Pa. This sensor can be integrated in the climate control equipment of livestock buildings to improve process contro

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1991.09-13.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

AbstractA parametric cost analysis was conducted to determine the importance of various system design and operating variables on t h installation and operating costs of active soil depressurization (ASD) systems for indoor radon reduction in houses. The objective was to help guide the research and development (R&D) efforts of the US. Environmental Protection Agency (EPA) to reduce ASD costs. Annual lung canter deaths due to radon cannot be reduced by more than about 14% to 22% unless houses having pre‐mitigation levels of 148 Bqlm3and less receive radon reduction systems. Reductions in ASD costs might increase voluntary use of this technology by homeowners at those levels. The analysis showed that various modifications to ASD system designs offer potential for reducing installation costs by up to several hundred dollars1, but would not reduce total installed costs much below $800–$1000. Reductions of this magnitude would probably not be sufficient to dramatically increase voluntary use of ASD technology. Thus, some innovative, inexpensive mitigation approach other than ASD would appear to be necessary. Decreased ASD fan capacity and increased sealing might reduce ASD operation costs (for fan electricity and house heating/cooling) by roughly $7.50 per month. It is unlikely that this amount would be a deciding factor for most homeown

ISSN:0905-6947    

DOI:10.1111/j.1600-0668.1991.10-13.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY