ventilation

This paper provides information of energy efficiency potential of Personalised Ventilation (PV) systems used in conjunction with a secondary Mixing Volume (MV) air-conditioning system in the tropics. The energy consumption and the acceptability of PV at selected combinations of indoor ambient temperatures of 26 C and PV air supply temperatures of 20 or 23 C, is compared with that of sole mixing ventilation in which the indoor air temperature was controlled at 23 C.

Isolation rooms for airborne infectious agents requires special measures to prevent air from transporting agents from the patient to surrounding rooms. This paper presents measurements for two different solutions that demonstrate that good results could be obtained by selecting construction principles that prevents air leakages and by control of ventilation airflows interlocked to door positions. Further it is estimated how different parameters influences on the transfer of infectious agents from the patient room to the surroundings.

The object of this investigation is a marketplace in a cold winter and hot summer region. This survey provides some basic data for HAVC designing of marketplace and the improvement of existed HAVC system in cold winter and hot summer region, at the same time it is suggested:
1. Due to bad smell caused by fruit and vegetables, it is suitable for supermarket to adopt deterministic directional airflow.

Tracer gas sorption in and permeation through building materials influence tracer gas ventilation measurements. The permeation of the commonly used tracer SF6 through three different building materials (gypsum board, wood particle board and MDF-board) with and without paint has been experimentally investigated. The results show that the tracer diffuse through untreated boards and that gypsum board has the largest permeability towards SF6. However, the diffusion rate of tracer is effectively reduced when the boards are coated with two layers of latex paint.

We report on a series of measurements of the temperature at Houghton Hall, Luton,over the Spring and Summer of 2003. The data show that the building tracks the externaltemperature, but that the amplitude of diurnal temperature fluctuations typically lies within 2-6 C,while the external fluctuations may be as large as 15-25 C. This buffering of the internaltemperature is largely due to the thermal mass of the space which introduces a time-lag ofbetween 0.5-3.0 hours in the response time of the interior to the exterior space, over the periodof our survey.

This paper describes a study on the performance evaluation of a hybrid ventilation systemwith a heat exchanger. This system has two passive stacks and a heat exchange unit, which includes a heat exchange element, a supply fan, an exhaust fan and a bypass route with a damper. In order to evaluate the system performance, the experiments and numerical simulations using a full-scale test house have been performed in winter or mild seasons. In the result, the ventilation rate and the heat recovery rate under the various conditions of the fan and the damper operation were clear.

As ventilation is a significant consumer of energy the rates of ventilation have often been minimized, particularly after the energy crisis in the early 70s, in order to reduce equipment and energy costs. This has caused in many countries indoor air quality problems. It has been shown that ventilation rates have adverse effects on communicable respiratory illnesses; on sick building syndrome symptoms; on productivity and perceived air quality. Often the prevalence of SBS symptoms is higher in air-conditioned buildings than in naturally ventilated buildings.

The paper examines the possibilities of using simple CFD models in practical smoke ventilationdesign. The aim is to assess if it is possible with a reasonable accuracy to predict the behaviour of smoke transport in case of a fire. A CFD code mainly applicable for ordinary ventilation design is used for the examination. The CFD model is compared with benchmark tests and results from a special application fire simulation CFD code. Apart from benchmark tests two practical applications are examined in shape of modelling a fire in a theatre and a double faade, respectively.

Ships are very demanding on the ventilation systems that need to be installed. The reasons forthis are manifold. The following paper will address the problems around the ventilation layout for a typical RoRo-Ferry and will show how CFD can help the designers to optimize the system. One new area of interest is the simulation of fire to optimize the fire suppression systems in engine rooms of RORO vessels.

This paper sums up the evolution of the AIVC technical programme over the past 25 years with its main subjects of interest and its main productions (guides, handbooks, technical notes, database, literature reviews).The communication between research communities and AIVC is also evoked along with its future developments.