A coupled BES-zonal model to predict stratification in a large building

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A decision-making methodology for selecting trigeneration systems

The paper considers the selection of a cogeneration system as a multicriteria decision-making problem, which involves economical, technical, thermodynamic and environmental issues. Taking into account the preference information given by the Decision-Maker (DM) about the weight of each criterion, a ranked set of alternatives is obtained by solving a discrete optimization problem based on the Tchebycheff metric. The problem definition, the structure and the solution algorithms are described. The DM can identify the most favorable alternatives in a finite number of steps. The method is illustrated with the help of an example

On modelling moisture buffering when evaluating humidity controlled HVAC systems

As most building energy simulation programs focus on the thermal response of the building, the relative humidity of the indoor air is often calculated in a simplified way. One of the main shortcomings is the isothermal calculation, which may have a strong influence the predicted relative humidity. In this paper the use of a simplified effective moisture penetration depth (EMPD) model is compared with a coupled TRNSYS-HAM-model. First, an estimation of the load for humidification and dehumidification is made. Results showed that the EMPD-model underestimates the humidification load because the model disregards non-isothermal effects. Secondly, calculations showed that the indoor and surface relative humidity of an office room with a gypsum cooled ceiling are overestimated using the EMPDmodel. Furthermore, due to not including nonisothermal effects the peak load for dehumidifying the ventilation air may be underestimated using an EMPD-model

The aid of TRNSYS simulation for the conservation of an artwork: a case study

Due to secularization more and more churches lose their original function, that is a place to worship, and become a place of cultural interest. To fulfil the comfort demands, a heating system or a HVAC-system was installed. These systems however impose new boundary conditions for the interior objects like paintings,. which may lead to damage. The case of the Saint-Bavo Cathedral in Ghent, Belgium is presented in this paper. In this church hangs the valuable polyptic 'The adoration of the mystic Lamb' painted by van Eyck. Use was made of a computer simulation to get insight in the working of different solutions to combine comfort and preservation. Because we want to be able in first instance to evaluate a whole year, a BES-software, was used. Using the dynamic simulation code TRNSYS the system performance in controlling thermal-hygrometric ambient parameters were obtained