Numerical and experimental device for local control of ventilation

Local control of ventilation in large buildings is considered to be a main issue in energy savings regarding the huge energy losses that are usually induced by such large volumes. An efficient ventilation system and the development of local control ventilation strategies could prevent large buildings from having an unsuited or overvalued ventilation and reduce significantly the energy consumption.

Experimental and numerical studies on indoor air quality in a real environment

This paper deals with the relevance of Computational Fluids Dynamics (CFD) results confronted tomeasurements carried out under uncontrolled thermal conditions. Experimental tests have been undertaken in a room and in a kitchen of an experimental house. Although the wall surface temperatures and the air intake temperature have not been imposed, the air change rates have been controlled during the measurements. Moreover, since measurements have been carried out in a real environment, air leakage has occurred at the walls.

CFD-based parametric study of ventilation and diesel exhaust in locomotive facilities

A CFD-based parametric study was carried out for a prototype general exhaust system widely used for ventilation and control of diesel exhaust in large enclosed locomotive facilities. The parameters of fan flow rate, ceiling height, fan spacing, and locomotive position relative to the fan were varied between two values representing the low and high ends of their expected ranges. A set of simulations was set up using factorial experimental theory, which allows variables and interactions having a significant effect on an outcome to be identified.

Standards indoor air quality involve a new design for ventilation housing system

In so far as natural ventilation system is totally dependent on local weather conditions and building facade elements, housing ventilation cannot be permanently guaranteed. This paper offers a computational flow simulation (CFD) which can be used to analyze housing ventilation under different buildings and weather conditions.

Study of air infection risk in the operating theatre

The ventilation system of a hospital operating theatre is designed to provide a comfortable andhealthy environment for the patient and the surgical team. A healthy environment can beachieved by minimizing the risk of contamination through an appropriate filtration and airdistribution scheme. The design and construction of operating theatres in Hong Kong,including the upgrading of the older ones, are based on the UK Health Building Notes andHealth Technical Memoranda.

Impact of turbulence anisotropy near walls in room airflow

Re-number k-e model is the most used turbulence model in Computational fluid dynamics. But sometimes that model does not produce good results and Reynolds stress model (RSM) improves the prediction of the velocity in the jet. Measurements and observations of streamline patterns prove it.

Different HVAC airside system designs of the surgical operating theatres : their impact on the surgery staff and patient health

There are several factors that affect the hygiene in the surgical operating theatres. The HVACairside system plays an important role to maintain the adequate hygiene level in the operatingtheatres. The present paper displays comparisons between different HVAC airside designs toassess their impact on the surgery staff and patient health and comfort. The present workutilizes a numerical modelling technique to predict local flow field characteristics, heattransfer and air distribution profiles.

Exploration of CFD models for personalized ventilation air terminal devices

Whilst Computational Fluid Dynamics (CFD) has been popularly applied in indoor air andventilation research, most Personalized Ventilation (PV) research is based on experiments.This study is an attempt to seek validation of PV experimental data with results fromnumerical models of Air Terminal Device (ATD), since the ATD is crucial in the simulation ofPV system.The CFD study involves a systemic study and comparison of various simulation methods ofPV ATD, aimed to develop PV ATD models for future whole room PV system simulation.Boundary Conditions (BC) are obtained from an elaborate set of me

CFD simulation of airflow characteristics of swirling floor diffusers

Air supply diffusers used in air-conditioning systems can be classified as ceiling diffusers,side-wall diffusers, floor diffusers, jet nozzles and low velocity displacement diffusers. Fixedor adjustable slats are usually used to control airflow directions. Recently, swirling vanes areused in floor diffusers to create a swirling out-flow jet, so that more rapid mixing withambient air can be achieved.

The use of CFD simulations for the assessment and improvement of a natural-ventilated hospital building

The objectives of the present work are to use computational fluid dynamics (CFD) to studythe airflow pattern and to evaluate the effectiveness of the passive cooling design of theproposed Jurong General Hospital (JGH) using natural wind. The complex three-dimensionalCFD model is used to assess the environmental conditions at the deep podium inside the JGHcomplex with prevailing wind conditions in Singapore, corresponding to the monsoon(November-February) and hot (March-October) seasons.