To protect the workers from stress with radiation heat in workshops, a study of the environment thermal state has been carried out. A local air supply to the workplace was provided through an air shower located either above the workplace or close to its floor. Operating measurements of thermal conditions were made along with an evaluation by using the WBGT(wet bulb globe temperature) index.The results of measurements and flow visualization show that the upper air shower is more suitable than the lower one.The optimum local air supply for hot workshops has been designed.
For the investigation of the personalized ventilation efficiency and the study of human exposure in a displacement and mixing ventilated room, a seated computational thermal manikin with the geometry of a real human body has been used. A RNG k-e model with low Reynolds number has been used for the simulation.
The thermal plume around the human body plays a key role for the determination of the inhaled air quality.
According to the authors, the application of personalized ventilation is able to improve the inhaled air quality greatly.
The vortex ventilator (VV) is a new concept of local exhaust ventilation system. In this paper the capture characteristics of the vortex ventilator are evaluated with both respect to the capture efficiency and to the capture velocity.3D CFD simulations are performed along with experiments using the tracer gas method with SF6.Comparison with the simple suction is made. The results of the VV are presented.
For that field study, measurements of different aspects of an UFAD (UnderFloor Air Distribution) system performance were made in an office building. The results show evidence of the benefits provided by UFAD on indoor air quality.
In this paper, the numerical methods are first validated by experiments, then a seated computational thermal manikin (CTM) is used to carry out the parameters study of Personalized Ventilation .The modeling outcome shows that in a stagnant environment, the human body is enclosed by the thermal plume and its intensity is affected by the room air temperature.To tear away the thermal plume at the windward side of the human body, a uniform airflow in the horizontal level with a O,2 m/s speed is strong enough.
The ventilation potential of buildings is widely affected by the building location, wind direction, space between buildings : so when high-rise buildings are too close, the influence of adjacent buildings on the availability of cross-ventilation has to be taken into account.
This paper reports the results of CFD simulation studies on that effect.
Filter performance of two new systems of simple respirators are investigated in this paper : a new method is used to quantify the real value of face seal leakage. The results show that respirators can't perform well because of the important leakage of airflow when they are mounted on the headform.
The study shows that physical characteristics of respirators such as the resistance and face fitting geometry are main factors to decide the leakage.
For that study, experiments are conducted to develop a new breathing ventilator using the concept of alternating-current (AC) ventilation. That ventilator is composed of a reversible fan and a thermal storage medium. In order to obtain the air change efficiency of a room by AC ventilation, numerical simulations are performed .
To face infection in hospitals, the control of the concentration of bacteria in patient rooms is necessary. For that study, computation and experiment were carried out in a real hospital isolation room. CFD software was used to simulate steady and transient air motion. A fog generated by an ultrasonic nebulizer was used to put experimental bacteria into the patient room.. The effect of bacteria removal by means of colony counts was examined. Both computational and experimental results proved that the original design of the isolation room could not remove bacteria effectively.
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