Tests were operated to analyse thermal stratification with undefloor air distribution systems supplying air at different rates and temperatures.

Literature was reviewed about underfloor systems and engineers having experienced these systems on completed projects were interviewed. Underfloor air distribution systems improve thermal comfort , indoor air quality and user satisfaction.

Natural ventilation’s fluctuating airflow has impacts on the thermal comfort and VOCs transportation in the naturally ventilated buildings. Research about the fluctuating characteristics of the airflow in naturally ventilated buildings was carried on in t

The purpose of this study is to clarify the usefulness of a displacement ventilation air-conditioning system introduced into a multipurpose hall after CFD simulation and measurement. In the multipurpose hall of Kurume City, a displacement ventilation air-conditioning system equipped with a floor outlet had been adopted. A CFD simulation for the purpose of selecting an air condition system indicated the floor outlet system would be more effective for the design plan of the hall than a ceiling outlet system.

In this article, four turbulence models are studied to capture the flow and temperature behavior of the air close to a low-velocity diffuser for displacement ventilation. Turbulence is modeled by means of one zero-equation model and three different two-equation models, i.e. the LVEL, the RNG, the Standard k-e, and the Chen-Kim model. They are evaluated for their performance in predicting the air flow patterns and temperature profiles close to the diffuser.

For a long time PPD index defined in international ISO7730 standard has been a practical tool for evaluation of measured thermal comfort conditions in existing buildings. However, its usage has not yet been realized in design phase. One of the reasons is that there has not been any practical tool available to estimate average velocity conditions within the occupied zone. A kinetic energy model for calculation of the average room velocity has been presented in earlier paper. Current paper reports additional verification results of the kinetic energy model with different types of diffusers.

The interferometric modeling of temperature fields allows to visualize clearly the distribution of temperatures in typical centres of ventilated and warm air heated spaces and spaces heated using radiators and walls. For the visualization the Mach-Zehnder interferometer is applied and the research is realized on diminished models by means of the similarity theory application.

In contemporary architectural design, the indoor climate receives little attention. Most architects are not familiar with the typical problems and solutions involved in climate design. However, it is this relation that provides much control over the initial climate conditions and can prevent costly artificial solutions. As a result, many design decisions are made without insight into the consequences on the indoor climate.

The control of thermal environment is complicated in buildings with glass-covered atriums. Numerical simulation can play an important role in the heating, ventilation, air-conditioning (HVAC) design of atriums. Many researches have developed various computational fluid dynamics (CFD) methods to accurately predict the thermal environment in atriums. However, a simple, reliable and fast method to deal with complex building construction is more suitable for building designers and engineers to take as a routine assistant tool of HVAC design.

The study presents a zonal model to evaluate the global comfort of air conditioned buildings. The model calculates various criterions such as Ppo and DR. Sound measure level is estimated with Sabine law. Comparisons with tests are presented.