simulation

The HVAC system in a real building was simulated by the energy simulation tool being developed (Ito et al. 2007, Sugihara et al. 2007). In order to confirm the practical utility of the tool, the studies are conducted on each phase: Program/Planning/ Design  phase, Construction phase, Pilot-Operation phase and Operation phase.

This paper describes the conversion of equipment characteristics into mathematical formulae, verification of the precision of said mathematical formula, and a concrete simulation tool. The main feature of this simulator is that operation of equipment is solved using temperature and flow, not calories. However, the characteristics of equipment are described using as simple a formula as possible. These formula are verified with actual values, and the simulator was confirmed to provide sufficient accuracy for energy management.

The importance of LCEM (Life Cycle Energy Management) has been recognized from the view of life cycle energy saving of sustainable buildings. The purposes of this research are proposal of an LCEM framework and development of prototype HVAC system simulation tools for LCEM. In this paper, necessity of energy simulation tools for LCEM is discussed, and the outline and solution method of the simulation tool are shown.

The aim of this research work is to investigate the actual energy consumption in existing public buildings and to obtain the basic data for energy conservation of these buildings. Various monthly energy consumption data of public buildings in Osaka for the period from April 2000 to March 2002 was gathered and analyzed to determine the nature of the energy consumption of buildings. One of the investigated buildings is selected as the typical building and the heat load is calculated. The calculated values of the energy consumption are compared with the investigation values.

Failures can lead to a series of problems in the complex heating, ventilation and air-conditioning (HVAC) systems in buildings. Fault detection and diagnosis (FDD) is an important technology to solve these problems. Models can represent the behaviors of the HVAC systems, and FDD can be realized with models. Using the model as intermediary, a link between system simulation and FDD can be built. Simulation has provided a convenient platform of operation for FDD, the overall simulation methodology in FDD of HVAC systems is briefly introduced.

The airtight window system adopted in highrise residential buildings or residential-commercial complexes recently in Korea gives rise to poor ventilation, deterioration of Indoor Air Quality (IAQ) and the overloading of cooling systems during the summer season. To address these problems, a slittype ventilation system has been developed. This study is to investigate the performance of the slit-type ventilation system using computer simulation. A thermal model coupled with an air flow network model which represents an apartment with an underfloor heating system was created.

We present a prototypically implemented and empirically tested daylight-responsive lighting systems control in buildings that makes use of realtime sensing and lighting simulation. This system can control the position of window blinds and the status  of the luminaires. It operates as follows: (1) At regular time intervals, the system considers a set of candidate control states for the subsequent time step; (2) These alternatives are then virtually enacted via lighting simulation.

This paper includes the results of empirical measurements in and computational modeling of atria. Five atria with different designs were considered. In each atrium reverberation times and sound distribution patterns were obtained via measurements. Subsequently, the spaces were modeled in a room acoustic simulation application. The comparison of measurement and simulation results support the formulation of recommendations toward a more reliable use of modeling tools for proper acoustical design and analysis of atria.

This paper presents the simulated results of human evacuation in a large space building. Two different models, Cellular Automata (CA) model and social force (SF) model are adopted. The simulated evacuation time and main characteristics of human evacuation are simulated and these results by the two models are compared. To check the practicability of the models for actual complicated cases, the simulating time is also compared. The results denote that both the two models can simulate the “arch” and “faster-is-slower” effect for human evacuation.

In order to determine the optimal combination of the heating source equipments in an existing office building, simulations of six different combination cases were conducted using the newly developed mathematical models of each component. From the simulation results, the optimal combination case can reduce the energy consumption by 19.7%, running cost by 12.8% and carbon-dioxide emissions by 29.6%, compared to the present operational combination.