IBPSA1999

In order to make proper radiative meshes with considering thermal distribution on solid surfaces, we inves- tigated the adaptive mesh generation method and per- formed parametric survey for a threshold which con- trols subdivision of mesh. With these studies we found that the adaptive mesh generation increase the accu- racy of predicting mesh surface temperature and air temperature even if the adaptive subdivision is rather soft one.

Air-conditioning systems with floor thermal storage can be used for cutting peak load and utilizing nighttime electric power. For the effective use of this system, however, thermal energy must be stored during the night in a way that does not waste energy. In this paper, an optimal heat input to such a system is investigated under prescribed external climatic conditions by making use of the optimal control theory.

Based on K- two equation turbulence model, we used PHOENICS 1.4 and numerically simulated air distribution and contamination field under different conditions in a vector- flow clean room. Special mesh system was introduced to deal with the quarter-circle- shaped inlets. Model experiments were also made. By analysis of numerical as well as experimental results, we made some predictions about flow characteristics, contaminant control effect and ventilation performance of this energy-saving clean room.

It is important to apply the natural light effectively for the low energy consuming daylighting design. A reliable standard sky is absolutely required that copies after the real sky luminance distribution for the simulation and evaluation of the daylit environment. Any applicable standard sky, however, has never found that shows accurately the actual state of daylight. A research work was carried out by the authors in order to establish a suitable sky model that can represent all the sky luminance distribution from the clear sky to the overcast sky continuously.

The research on provision of computational support for building performance analysis has traditionally concentrated on the building design phase. However, computational modeling can also effectively apply to the building operation phase. To explore this potential, we consider in this paper simulation- assisted control strategies to integrate contextual forces  (specifically  daylight)  into  building control systems.

In order to explain the effect of ventilation systems and airtight performance of houses in detached houses, the investigation was made on a simulation program which calculates the ventilation rates and indoor air quality. The ventilation rates and the concentrations of CO2 , CO and formaldehyde in general Japanese houses with three kinds of ventilation systems were calculated through a year in three cities of Japan. The results of the simulation showed a case in which the concentrations of the pollutants are not acceptable.

This paper introduces a method to simulate the day-light performance of buildings using geostational me- teorological satellite images. A new statistical method enables to estimate global and direct solar irradiance values at hourly intervals by the pixel values of satel- lites images. Luminous efficiency functions convert the global and direct irradiance values into diffuse and direct daylight illuminance values. The daylight source model is combined with a daylight calculation program to calculate spatial and temporal distributions of illu- minance and luminance.

Simulation  of  cleaning  is  a  new  area  in  building simulations. To make rational cleaning is it important to know how difficult it is to clean rooms. I define a Cleaning Index (CI) as the cleaning area divided by the floor area. High CI is difficult to clean. A simulation program CIX calculates the CI based on an object-oriented 3D model of a room in the VRML-format. The program will find all horizontal surfaces, where the dust can settle. The result is presented in graphical form or in tables. Use of the method is shown for a  classroom  and  two  offices.

The purpose of this study is to develop the technique that mixing energy loss is predicted at the time of the air conditioning system design by the simulation. If air conditioning load, which contains mixing energy loss, can be calculated easily at the time of air conditioning system design, we can design most suitable air conditioning system which mixing energy loss doesn't occur in. In this paper we would like to examine simulation macro model which  has following characteristics.

An  integrated  simulation  system  for  the  building services design and facilities management purposes is being developed by Olof Granlund Oy. The system covers the thermal  simulation needs of the whole building life cycle from the preliminary design to renovations. The main components of the simulation system are simulation database, result module, calculation engine, which are all built in to a user interface RIUSKA, and building geometry modeller, SMOG. The building geometry modeller generates a 3-D surface model of the building and has IFC 1.5 import/export capabilities.