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Is it possible to improve the simulation speed? The simulation speed depends highly on the number of openable windows in the model. A model without openable windows runs in 1-2 minutes, while a model with 6 openable windows runs in approximately 10 minutes.
The way windows are modelled in the EIC Visualizer will be further optimised in a future version to improve the simulation speed.
Can I use the EIC Visualizer to show that I meet the legislative requirements in my country? No, the EIC Visualizer is a general simulation tool. Each country has its own energy legislation and some countries require that specific calculation methods are used. The EIC Visualizer will provide an accurate estimate of the building’s energy demand, but it may differ from national calculation methods.
How accurate is the EIC Visualizer compared to other simulation tools? The EIC Visualizer is based on IDA ICE, which has been continuously improved and validated since 1989 and is among the state-of-the-art simulation tools commercially available today, so the EIC Visualizer is founded on a solid base. The EIC Visualizer uses detailed climatic data and makes an hour-by-hour simulation of the year with each hour divided into many small steps. This allows very detailed calculation of natural ventilation flows, and the EIC Visualizer is particularly strong in natural ventilation.
The fixed building geometry does not fit the project I am working on – what should I do? It is possible to calculate a reasonable estimate of the energy demand of a building with the EIC Visualizer, also if the actual building differs from the built-in options of fixed geometry. The geometry, which is closest to the actual building as regards floor area and length/width ratio, should be selected. Windows should be selected so they match the actual building with regard to the percentage of windows per floor area. This approach will provide reasonable results for energy demand (in kWh/m²) and ventilation rates (in air changes per hour, ACH).
There are no internal walls and doors in the model. How does that affect the results? The EIC Visualizer does not consider internal walls as barriers for air flow and heat transfer because the building’s energy demand for heating, cooling and ventilation is only affected insignificantly by internal walls. The average indoor temperature of the building is also only affected to a small extent. Internal walls have a thermal mass and this effect is included in the EIC Visualizer by including a reasonable area of internal walls in the models.
However, the temperature distribution between rooms in an actual building will not be uniform and this effect cannot be investigated with the EIC Visualizer.
Is it possible to make a multiple selection of windows? No, to change the properties of several windows, it is necessary to select each window individually.
I have chosen mechanical ventilation with a fixed ventilation rate of 0,5 ACH, but the results show some variation in the ventilation rate – why? This is due to a technicality and is not an error. The EIC Visualizer uses mass flow instead of volume flow when determining the flow rate. The mass flow rate is kept constant, but as the density of air increases as the temperature decreases, the volume flow will be a little below 0,5 ACH when the outside air temperature is below 20°C.
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