English

An absorption chiller model is developed for HVACSIM+(J). The model simulates dynamic characteristics of the chiller, such as dynamic trends of chiller temperatures and COP. The total system simulation including the chiller and the other HVAC system enables to evaluate energy consumption for the HVAC systems and how much the system save energy. Furthermore, the simulations show the effect of the control strategies. In the paper, the chiller model is described, and the simulation results which contain independent chiller system and a total HVAC system.

In multizone models used to predict thermal comportment of buildings and inside air quality, representation of the airflow through large vertical openings is very important. Both physical representativeness and numerical stability of the large opening model are essential for a successful multizone modelling.

We developed a PC-software to estimate thermal environment of a residential house. To make the software practical for non-technical people, the easiness of operation was our main interest in this development. This led us to adopt a fully graphic interface, dynamic database of the structural walls and a comparative output of the thermal estimation. As a result of error comparisons within various numerical methods, we decided to use the full implicit finite element method to calculate the transient heat flow in the walls.

A systems approach is developed for predictive operation of HVAC processes in buildings, which is described with an objective function, a state-space model, and a number of constraints. The state-space model is transformed from z-transfer functions that are identified in real-time. The system constraints are described mathematically so that they can be easily applied. Dynamic programming techniques are combined with on-line simulation to enhance efficiency in searching for the optimal operation strategies. Simulation studies show that the techniques are computationally efficient.

The typical Korean residential buildings, especially apartment buildings, are furnished with ONDOL – the Korean traditional radiant floor heating system. The buildings are getting more insulated and air tight for heating in hard winter. ONDOL floors and walls are heavy enough to take up large thermal capacities for the better efficiency of the heating system. The developed computer simulation program could well predict that the heat- equivalent to 5 continuous hours of hot water supply - is intermittently supplied even on the coldest day in Seoul, Korea.

Several features of heat transfer on enclosing surfaces is discussed including temperature distributions in a room heated by a floor heater. Experiments and numerical analysis on radiative and convective heat transfer were carried out against several partial floor heating. Partial floor heating produces different types of temperature distribution between the heated and non-heated places, which is an remarkable characteristics found out in this study. In the heated places, the temperature distribution is almost the same as that of typical floor heating.

An evaluation system of the visibility of a ball flying is indispensable for the best architectural design and artificial lighting design of a baseball dome stadium, as it is essential to create a suitable visual environment for both players and spectators to watch the ball. This paper describes a simulation theory of the visibility of balls flying in the baseball dome space proposed by the authors and shows the recommendable reflectance of the construction material and suitable artificial lighting system by the simulated results of a model dome stadium.

The objective of this study is to improve the control performance of Ondol heating system in apartment buildings. For this purpose, prevalent control systems and relevant researches are evaluated.

This paper provides an overview of the usage of performance-based simulation tools for building design and evaluation in Singapore based on an extensive industry survey. It highlights the status and difficulties encountered in the usage and the needs of the industry for such tools. Recommendations are also given to promote the pervasive use of such simulation tools.

Within the research context relating to the modeling process of architectural buildings and landscape planning, the CRAI particularly works on the simulation of day-light and artificial illumination. The purpose of this research is to develop a software platform dedicated to project design, since there are no overall tools integrating all the answers to our needs.