Performances on Indoor Air Quality and Energy Consumption in the Working Spaces using Under-floor Air Distribution (UFAD) System.

Arthur Rosenfeld cited a study showing that the huge link between IAQ and productivity in anoffice building and the serious initiative to improve indoor air quality will have a tremendous return. This study attempts to analyze the working spaces with different variances. The chamber measurements in the laboratory constructed in Shu-Te University will be taken, and the numerical simulation using CFD techniques will also be applied. The results from both should be compared. The different inlet layout of HVAC system, especially the UFAD system, and the boundary conditions will be discussed.

The Characteristics of Wall Confluent Jets for Ventilated Enclosures

This paper reports experimental measurements on the diffusion of confluent jets thatform a wall jet. The experiments were carried out at a fixed air flow rate and fixed temperaturedifference between the supply and room air in the cooling mode. Based on these experiments, theresults presented show the behaviour of the wall confluent jet in the form of velocity profiles, thespreading ratio of jet on the wall, etc. The empirical equations derived are compared with othertypes of air jets, such as the free confluent jet, free plane wall jet, and free plane jet.

Towards making the indoor climate visible in practice

This paper deals with how to visibly render the thermal climate in the design and presentationtools used by different participants in the building process. The focus is on those ventilation/coolingsystems where cool air is supplied directly into the occupied zone and therefore have a potential ofgenerating a volume close to the device with poor comfort. This volume could be described as a spreading bubble. In the paper a practical procedure for rendering the spreading bubble is presented. This is achieved in a number of steps.

Numerical Study of Thermal Response of School Buildings in Winter Conditions

In this work a numerical model, that simulates the buildings thermal response and evaluates theinternal air quality in transient conditions, is validated and used. This multi-nodal model calculates notonly the buildings temperatures and the air water vapour and contaminants mass, but also the air relative humidity inside the spaces, the solar radiation inside and outside building surfaces, the heat and mass convection coefficient, the views factors between internal surfaces, the heat and mass fluxes and the global thermal comfort level.

Flow in the plenum of a UFAD system

We describe the flow in an underfloor plenum. We show that the geometry of the plenum causes the flow to exhibit two-dimensional dynamics and to develop flow patterns that are determined by the inlets of the underfloor into the plenum void. We describe laboratory experiments that simulate these flows and also show that the location and number of diffusers in the plenum has little effect on the underfloor flow. Depending on the location of the inlets to the plenum, the flow can exhibit complex vortex patterns and may be time dependent.

Floor-Supply Air-Conditioning System in a Theater Hall

Floor-supply air-conditioning system with Coanda effect is introduced to a theater hall. This system supplies air from floor diffusers set beneath the seat backrest in front of occupants. Supplied air moves upward along the backrest board inducing the circumambient air resulted in airflow temperature difference reduction. Thermal environment was measured under various heat load conditions in the theater hall. Supply air flow along and radiation effect from the seat backrest in front were confirmed using the floor-supply system.

Design of Load in Thermal Network Models

The paper describes the use of a synthesis in thermal network models. Simulation methods areusually based on an analysis when the optimal solution is found by means of iteration process. Presented method is developed in a frequency domain for models that are built as electric circuits. General description of the method with used equations is given. The application is demonstrated in a case study when a cooling power for one room in light-weight building is found. Resultant values are time dependent internal cooling load that ensures desired inside air temperature during summer day.

A Three-Dimensional Numerical Study of Convective Heat Transfer from a Window with a Venetian Blind

This paper studies in three-dimension the coupled convective and radiative heat transfer rate from awindow surface with adjacent venetian blind using a commercial CFD code. For this study the window surface was modeled as an isothermal vertical flat plate. The flow patterns (temperature and velocity fields) and convective heat transfer coefficient were investigated for different blade angles (00, 450, -450, 800). Comparisons were made with experimental and other theoretical research.

Energy performance of the naturally ventilated building

One of the main arguments supporting the application of the natural ventilation is the reduction inenergy consumption and capacity of the HVAC system. Here several tests of the building with different systems are carried to quantify the differences in capacities and energy consumptions of different solutions for the HVAC system. The tests were carried with the simulation program built in Simulink. To validate the model the measurements were done in Test cell at TU Delft as well as in the real office building.

Influence of solar radiation on heat and air flow transfers in double skin facades with venetian blinds.

A comprehensive modelling of a compact double skin facade equipped with a venetian blind is proposed here. The modelling is done using CFD approach to asses the air movement inside the ventilated facade channel and appropriate radiation model for long and short wave exchanges. The impact of solar radiation on temperature and velocity fields as a function of some parameters such as beam radiation incidence angle, blade angle of solar protection, etc. is analysed.

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