Series:

Technical Note

13 total works

TN 5/92

Cover of Prediction of Temperature Gradients in Large Buildings
This document provides design guidance information on the efficiency of different methods of reducing stratification, considering different building heights, constructions and destratification systems. It also provides data on the likely percentage energy savings from the different systems given the initial stratification. The work comprises computer simulations using computational fluid dynamics to predict the performance of various methods of reducing stratification. Two stages were undertaken. Firstly, modelling of existing buildings, for which measured data was available, to demonstrate the ability of the computational technique to predict the environment. Secondly, modelling of different de-stratification systems in otherwise the same building and outdoor conditions to provide a direct comparison. It is the design information from this work that this publication addresses.

TN 3/93

Cover of Displacement Ventilation Performance

TN 5/83

Cover of The Effect of Maintenance on Boiler Efficiency
This title describes a study carried out on 14 boiler installations under site conditions by monitoring flue gas oxygen content and temperature together with ambient air temperature to enable the combustion loss to be calculated. By undertaking the tests on boilers in both clean and dirty conditions, and recording data every minute over a period of two to three days, representative mean combustion loss figures were obtained. The combustion loss was calculated according to BS DD65 "Methods of type testing heating boilers for thermal performance. Part 1. Direct Method". The results of the study indicate the problems of producing accurate information about the performance of boiler plant under working conditions. Combustion loss figures ranged from 14.99 per cent to 29.33 per cent. Efficiency changes ranged from + 4.98 per cent to - 3.31 per cent but most changes were less than 2 per cent. The book finds no firm evidence of improved performance after maintenance and suggests further guidance is necessary on the level and frequency of maintenance required, together with some means of showing that adequate maintenance has been carried out.

TN 1/92

Cover of Low Temperature Air Cooling Systems
In recent years, cooling systems with low-temperature air have gained in popularity within the building services profession, both in Europe and North America. The original motivation for such systems was reducing the space requirements and energy costs. In these systems, air can be delivered to spaces at temperatures between 3 degrees C and 11 degrees C dependent upon the design of the system and technology used. This is in contrast to the conventional cooling systems where air is delivered in the region of 13 degrees C to 15 degrees C. The reduced supply temperature leads to a lower conditioned air volume requirement and consequential reduction in plant and duct size. Furthermore, energy costs can be reduced, particularly, when low-temperature air systems are linked to some form of thermal storage which uses off peak electrical power. Nevertheless, as with all novel systems problems can be encountered. This technical note intends to give guidelines to the use of low-temperature air systems, with particular emphasis on room movement.
These guidelines have been developed from computer-based predictions of the thermal environment in a typical two-person office, cooled by low-temperature air supplied through slot diffusers.

TN 6/86

Cover of Inspection of Building Services Plant and Equipment
This title describes an investigation of the role of inspection in maintenance of building services. The work was done by interviewing two maintenance contractors, five building operators and and a specialist inspection organisation, together with a postal survey of 50 maintenance contractors. It describes inspection as "the process of determining if and what maintenance is required" and examines why inspection is undertaken, by whom and how. The book concludes that there is minimal evidence that formal inspection is acknowledged as necessary by either building operators or those offering a maintenance contract service. It also discusses inspection as understood by maintenance contractors and building owners, together with inspection frequencies, instrumentation and documentation.

v. 8/98

Cover of Refurbishment of Air-conditioned Buildings for Natural Ventilation
It has been demonstrated in a number of case study buildings that it is possible to maintain a comfortable environment when refurbishing without resorting to full mechanical ventilation or cooling. This note presents guidance for refurbishing air-conditioned buildings to utilize natural ventilation. It is particularly appropriate where conventional naturally ventilated buildings are to be upgraded to incorporate passive cooling techniques.

v. 17/98

Cover of Environmentally Friendly Heating Products

TN 1/85

Cover of Planned Maintenance and the Use of Computers

v. 18/98

Cover of Environmentally Friendly Lighting Products

v. 16/98

Cover of Environmentally Friendly Cooling Products

v. 19/98

Cover of Environmentally Friendly Water Systems

TN 7/2001

Cover of Rainwater and Greywater in Buildings
Written for those installing rainwater and greywater systems or monitoring them, this report forms one of the published outputs of "Buildings That Save Water", a major research work undertaken by CIRIA and BSRIA between February 1998 and June 2000. During the research detailed monitoring took place at seven demonstration sites where rainwater or greywater systems were installed. Each site was monitored for up to 12 months to evaluate the operational performance of the system. Additional information was obtained from a variety of other sites and studies. The report includes general recommendations on best practice for rainwater and greywater use.

TN 2/96

Cover of Displacement Ventilation and Chilled Ceilings
There is currently an upsurge of interest in the application of uoyancy-driven displacecment ventilation systems and chilled-ceiling devices in the office environment within the UK's heating, ventilation and air-conditioning industry. As part of a series of research projects in the field of displacement ventilation, the BSRIA has undertaken a programme of work to investigate whether it is feasible to combine displacement ventilation systems and chilled ceiling devices while still maintaining adequate levels of thermal comfort and a predominant upward air movement. These studies were achieved by using both physical measurements and numerical modelling based on computational fluid dynamics (CFD) techniques. When displacement ventilation without cooled ceilings was considered, the airflow patterns were chiefly upward when the internal thermal loads were equivalent to the cooling capacity of the displacement ventilation system. On condition that the supply air temperature and air velocity were maintained within recommended values, a high order of thermal comfort and air quality were predicted.
The addition of chilled beam devices to offset higher internal thermal gains progressively eroded the predominant upward air flow region as thermal loads were increased. Indeed, when the cooling load of the chilled ceiling devices was about three times that of the displacement ventilation system, the flow field was virtually similar to a conventional mixed airflow system, except in the vicinity of heat sources where upward convective plumes entrain air from the displacement cool air layer at floor level. The simulation of displacement ventilation with chilled panels, however, showed that the radiant cold panels slightly increased the depth of the mixed warm and contaminated upper region, but it did not affect the displacement airflow characteristics of the lower part of the room. The environmental thermal comfort conditions, however, were of a very high order in all cases considered.