This research proposes a method for task area wide-cover personal air conditioning thatprevents a human body in the task area from being exposed to a largely irregular thermal environment. A Particle Image Velocimeter (PIV) was used in the research to measure air flow fields for conventional spot cooling and wide-cover personal air-conditioning(PAC) around the human body. The wide-cover type PAC formed a calm air flow field of less than 0.18m/s around the human body, while the spot cooling type PAC formed an air current of 0.3-0.6m/s around the area of the neck.
This study presents the results obtained when Computational Fluid Dynamics is applied tocalculating the flow in a domestic kitchen hood at operating conditions. Special emphasis has been placed on parametric modeling of the geometry to permit the rapid modification of fundamental parameters, such as the number of blades and the twisting angle. The governing equations (mass, momentum, energy and turbulence) have been solved using the commercial code, Fluent.
The method of exposure prediction using the scales of accessibility of supplied air (ASA) and the scales of accessibility of contaminant source (ACS) is presented in this paper. The spreading performance of supplied air and indoor pollutants can be figured out by CFD simulation and then used for the prediction of contaminant dispersion. For the validation of the model, a traver gas measurement was conducted.
The aim of the study is to evaluate the possibility of ensuring an indoor climate within an acceptable range thanks to the use of large exposed massive wood surfaces. The description of the experimental study performed in four occupied flats of a multi-storey residential building in Sweden is made in this paper along .The analysis of the in-situ recordings is presented too.
The design of ventilation performance of air-conditioning systems in residential buildings is not quite established. In this paper findings from a recent study of the ventilation performance and IAQ in a master bedroom in Singapore are presented. The need to design for ventilation provision in split system air-conditioning units is suggested by the findings.
In a VAV system, it is possible to minimize the energy use with an optimal supply air temperature. The theory for such a device is presented. The analyses show that controlling the supply air temperature in an optimal way results in a decrease of HVAC energy use compared with a constant supply air temperature.
A PMV (predicted mean vote) index is often adopted to assess the thermal comfort conditions of thermal moderate environments, but to prevent problems when monitoring or controlling HVAC equipment a fuzzy adaptive controller has been introduced. That paper gives a description of the method along with the presentation of simulation results .
The main aim of that study is to assess the status of natural ventilation in a typical four-room HDB (Housing and Development Board) flat in Singapore using scaled model in the wind tunnel and also to develop an effective passive or active stack system to enhance natural ventilation in the flat.
Sick syndrome episodes were reported by the employees of Athens Air Traffic Control Tower (ATCT). In this study recent indoor air quality measurements made in ATCT are presented and discussed. The data indicated that VOCs concentrations were above outdoor levels in certain places of the building, some actions were taken to improve the indoor environment and afterwards a second set of measurements were made, inside and outsite the ATCT building : the results indicated an improvement of the indoor air quality.
Designing an HVAC system has different aims, the first one is to satisfy the user with a long-term functioning system in the most energy efficient way and the second is to increase the supply air flow. So the main objective of this paper is to give the fundamentals for a system design that takes into account the 3 factors. The benefit of a pressure controlled variable air volume (VAV) system is presented .