Numerical Investigation of the Airflow in a Kitchen Hood

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.

Experimental Comparison of Thermal Environment between Ceiling-based and Floor-based System with CAV HVAC System

The present paper evaluates indoor thermal environment, cooling efficiency and energy consumption between a floor-based system and a ceiling-based system using a mock-up model in cooling period. The experimental chamber has a UFAC, underfloor air conditioning system and a ceiling-based system. And the experiments are set with practical internal load conditions including occupants, lighting units, and heat sources (office automation equipment). The following were compared and evaluated;
1) the vertical and horizontal temperature distribution,

Microbiological Quality of Air in a Bread-making Factory

The microbiological quality of air was studied in a bread-making factory (100t/day). It wasnoticed that the microorganism density varies along the fabrication hall, a high number of microorganisms, especially moulds, being registered in the bread cooling area and the storage room. In the bread cooling area predominate Penicilllium expansum spores, this mould being able to develop at low aw values and determining the bread spoilage.

A Case Study of Quantitative Energy Efficiency of Personalized Ventilation in the Tropics

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.

On the IAQ Characteristics of Child Care Centers in the Tropics Arising from Different Ventilation Strategies

The IAQ characteristics and the corresponding health symptoms and thermal sensation of the occupants of child care centers in Singapore under 3 different ventilation strategies are reported. The 3 child care centers studied were centrally air-conditioned and mechanically (ACMV) ventilated (Case A), naturally ventilated (Case B) and hybrid (natural and air-conditioning) ventilated (Case C).

Natural ventilation of an apartment: a case study

This paper refers to the use of natural ventilation in Portuguese urban housing stock. In order to assess the goodness of natural ventilation design rules defined in a new Portuguese standard, a research project is being carried out. The results of the measurements of temperature, humidity, flow rate in ducts and weather conditions taken at an apartment in Matosinhos are presented.

Lower energy cost and less sick leave with displacement ventilation versus mixing ventilation

Experiences from cleanroom installations has frequently shown that displacement ventilation has a much higher efficiency than mixing ventilation with respect to particle and CO2 reduction, cooling efficiency etc. Another cleanroom experience is that low particle concentration benefits asthma and allergy sufferer. Low particle concentrations reduces the impact of other pollutants and enhance the quality of life for everybody. In an office, the level of discomfort this means less tiredness, better concentration and lower absenteeism.

Complex Air Flow Behaviour in Complex Spaces - Design Optimization by CFD, Realization and Visualization

This paper shows the successful application of CFD simulations for analyzing complex room air flow problems in real applications and deriving optimized solutions.

Study on Compatibility of Energy Conservation and Thermal Comfort in Japanese House with High Air-tightness and Insulation equipped with H.V.A.C. System

The compatibility of energy conservation and thermal comfort in Japanese house with high air-tightness and insulation equipped with the whole-housing heating, ventilation and air conditioning (H.V.A.C.) system was examined by a numerical analysis. In addition to the present situation, several scenarios for achieving the compatibility were supposed. Thermal environment, thermal comfort and electricity consumption of H.V.A.C. system were analyzed throughout a year for each scenario. A combination of proper scenarios was found to be achieved the compatibility.

Ventilation of isolation rooms in hospitals

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.

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