IBPSA2003

Condensation    and    mold    problems    have    been identified as one of the severest IAQ problems in Japan. Especially in the wintertime, moisture condenses on cold wall surfaces where it can cause deterioration of the building materials and mold growth related to allergic symptoms. This paper discusses the possibility of using the CFD method to solve condensation problems. Firstly, a CFD model for simulating condensation is developed, and then the validity of this model is examined experimentally.

The EnergyPlus building energy simulation software has been tested using the IEA HVAC BESTEST E100-E200 series of tests. The Volume 1 final report for the International Energy Agency (IEA) Building Energy Simulation Test and Diagnostic Method for Heating, Ventilating, and Air-Conditioning Equipment Models (HVAC BESTEST), was recently published in January 2002. HVAC BESTEST is a series of steady-state tests for a single-zone DX cooling system. Cases range from dry to wet coil, low to high part load, and low to high temperatures.

This paper documents work that follows on from a previous study [Morbitzer et al 2001] on the implementation of a simulation-tool into an architectural practice at outline design stage. The use of simulation is now pervasively and routinely undertaken by designers within the company to evaluate energy and environmental performance of their design concepts. The paper documents the changes to the interface, based on the feedback from designers.

The purpose of this study is to gain insight into the process of heating a room with a low-temperature radiant heating system and solar energy, considering energy conversion and heat transfer steps in the building (where heat is required), in the incident solar radiation (which supplies part of the heat required) and in the heating system (which provides for the additional heating needs, by using electricity from a gas-fired power plant to drive a heat pump). We applied a theoretical framework developed by Shukuya, et. al.

The  most  dominant  moisture-related  problem  in building materials is probably mold growth. It occurs as a result of relatively high moisture concentrations. Although recent research has established the causal, physical-biological relationship between moisture content, temperature, material type, and mold growth, we do not have an established set of causal relationships between certain building parameters (such as envelope characteristics) and the risk  of mold growth.

At the new institute building of Fraunhofer ISE, both mechanical and free night ventilation is used for passive cooling of the offices. The results from a monitoring of room temperatures in 21 office rooms during summer 2002 show that room temperatures exceeds 25 °C in less than 8 % of the working hours, even at high ambient air temperatures. In two offices, experiments were carried out in order to determine the efficiency of night ventilation dependent on air change rate, solar and internal heat gains. During the experiments, meteorological data, air change rates, air temperatures (incl.

This   paper   demonstrates   an   experience   in   the development  of  a  design  performance  evaluation system that can frequently evaluate building design performance within the design process in a real-time manner.   The   evaluation   system,  that we   call "Vitruvius Studio," is composed of several modules such as a front-end component-based CAD engine, a knowledge base, and a set of design agents.

This paper will address the shortcomings of typical heat balance-based HVAC design and analysis software when applied to thermal displacement ventilation (TDV) system design. The performance characteristics of thermal displacement systems that lead to inaccurate calculations from heat balance- based programs are discussed. Finally, the paper presents an approach for estimating the performance of TDV systems using existing heat-based calculation tools that responds to most of the significant differences between overhead  mixing systems and thermal displacement systems.

We present a method, a model and a simple design tool for evaluating the construction, investment and energy costs of different possible design alternatives for grouping apartment units into a multifamily residential building. The added investment cost of each design alternative, compared with a bench-mark solution, is expressed in terms of Additional Annualized Mortgage Payment (AAMP) and is traded-off against possible saved Additional Annual Electricity Payment (AAEP) for in-house climate control.

The present paper describes the development of a method where simulations combined with measurement of parameters for each apartment such as temperatures and relative humidity in the exhaust air and electricity consumption, are used as a basis for individual energy billing. With simulations a transfer function between total heat consumption in the building and in the measured parameters for each apartment is calculated for estimating the individual contribution to the total heating energy used in the building.