Trial / Demo
This summer, IES ran a series of live lecture-style sessions for our audiences in North and South America, covering key analyses that can be undertaken using IESVE software. Over 900 questions submitted across the 6 sessions – and it became apparent that several key themes emerged within the questions asked. Read on for the answers to these questions, for which we turned to our team of experts to answer.
When importing .gbxml files from Revit, it can lead to errors, such as surface intersections, holes or unmatched adjacencies. Is there a way to solve this?
You can easily import files from Revit or Rhino using the Pollination Plug-in. IES have collaborated with Ladybug Tools so that Pollination directly imports using IESVE native file format (.GEM) rather than gbXML or IFC. The plug-in lets you quickly find and fix any geometry errors, whilst improving workflow productivity and enhancing project collaboration. Find out more about Pollination here.
It can be hard to see different room types when the walls are represented by a single line. Is there a way to make these different types more obvious?
Yes – you can change the colors via Tools > Colour Preferences.
What is the difference between thermal templates and zones in ModelIT?
Thermal templates are a way of applying a common set of inputs to spaces. They include data like internal loads, conditioning setpoints, and ventilation requirements. Zones on the other hand are associated with the assignment of spaces to an ApacheHVAC system and can include multiple spaces. The basic idea being that all of the spaces included in a single thermal zone would be controlled by a single thermostat.
When are the design weather data and simulation weather file used?
Design weather data is used for room load and system sizing calculations, whereas a simulation weather file is used for dynamic energy simulation. A common source of design weather data is ASHRAE Handbook of Fundamentals – Chapter 14. There are a variety of sources of simulation weather data many of which are linked through the IES website at the link on the Start Page. These files provide global coverage, with free and paid options available. Find out more here.
Find out what other questions were answered on the session, available on-demand now.
Are there options to import window information?
Yes, glazing materials can be imported from our manufacturer database. You can also download specifications from the International Glazing Building Database (IGDB). Find out more about this process here.
Can u-values be adjusted to meet specific requirements of a project?
Yes, u-values can be adjusted by editing the cavity resistance in a glazing assembly. Find out more about this workflow here. You can also generate a window utilizing a target U-value by right clicking on any construction.
Can IESVE calculate sunlight exposure for interior spaces and exterior surfaces?
The SunCast application within IESVE measures solar exposure and received energy on exterior surfaces. To calculate the solar exposure for internal spaces, the RadianceIES application can be used instead. Find out more about SunCast and RadianceIES.
Find out what other questions were answered on the session, available on-demand now.
Can I create my own thermal template and transfer this to different projects?
Master Templates within IESVE allow users to import and merge VE model data from a source master template into an active project. Custom templates can also be created for specific project properties and shared between projects using the Master Templates functionality. Watch our Tech Tip on the Master Templates Wizard here.
How can I tell which template is applied to each room?
Data assigned to your IESVE model can be visualized with the “Input Data Visualisation” feature in Model Viewer II. This feature allows you to view variables such as thermal templates to internal gains. Find out more about the Input Data Visualisation tool here. You could similarly select the group of spaces that you are curious about and use the Tabular Space Data tool which lists the thermal template assigned to each space on the General tab.
If I am only using IESVE for heating and cooling load values, do I need to set a space/room group assignment?
It depends on your project. If your project has thermal zones that include more than one space then yes, HVAC zones must be defined using the HVAC Zones and Zone Groups view of the model in order for accurate heating and cooling loads to be determined.
If, on the other hand, each space in your model is its own thermal zone, the use of room groups and thermal zoning are more a matter of personal preference. However, using these will greatly improve the efficiency of assigning spaces to multiplexes in ApacheHVAC.
Is there a way to change the default dates when calculating loads?
For load calculations, one day represents the whole month, which is the worst-case scenario of temperature and solar radiation for that month. This is referenced in the ASHRAE Handbook – Fundamentals. The range of months considered for cooling load calculations and the month considered for heating load calculations is editable in the ASHRAE Loads dialog by unchecking the default checkbox prior to launch the calculation step.
Find out what other questions were answered on the session, available on-demand now.
Can I jump straight in with ApacheHVAC?
Before starting ApacheHVAC, the geometry, construction and thermal templates must be completed.
Can the systems within ApacheHVAC be customized?
Yes, all systems within ApacheHVAC are designed to be customized as the Prototype Models are intended to be starting points to work from. Our recommended workflow is to turn off components and/or controllers referencing equipment that you do not want to include, rather than deleting those components.
Is it recommended to leave as default or whole year for cooling months?
It depends on your climate and internal load conditions of your specific project. In some cases, it is obvious that the cooling peak will occur in the summer (e.g., Phoenix, AZ), so; therefore, the default setting will reduce your run time and results file size.
If it is not clear when the cooling peak will occur through the year (e.g. San Francisco, CA), then expanding to the full year makes sense, depending on climate. For cooling loads, a combination of high temperature and worse case solar radiation determines the peak. Some zones peak at low solar radiation, not in summer.
Should internal gains in heating load calculation be checked for more accurate calculations?
This entirely depends on the nature of your calculations. For Room/Zone loads calculation and HVAC System Sizing calculation, you want to understand the peak conditions. This means for heating, the internal gain would be OFF, and for cooling, the internal gain will be ON. However, for dynamic hourly simulation these gains will be included.
Can different HVAC systems have different schedules?
Yes – the system availability can be set up within the “Schedule” tab of the “System Parameters” window. User will need to create a “New profile set.” Find out more about the System Parameters dialogs here.
What is the recommended workflow for mechanical engineers and energy modelers working on the same project to determine loads/sizing?
The best workflow would be to share a common model between the HVAC design and energy modelling teams. However, it is possible to update an energy model based on loads data from a separate software.
Find out what other questions were answered on the session, available on-demand now.
Can IESVE be used for retrofitting as well?
Yes – we have many users using IESVE for existing buildings as a Digital Twin. Find out more about our Digital Twin solutions here.
Is it possible to create customized reports?
Users can use Python scripting to generate their own reports. Python scripting can also help with data input, parametric simulations and many other tasks to maximize productivity. Find out more about Python Scripting in IESVE here.
What is the average runtime needed for the simulation to create a report?
It depends entirely on the complexity of the model. For example, a model of a single room might take less than a minute, whereas a very complex model can take upwards of 10 minutes. This is also highly dependent on the computer performance.
Can variables be changed within the dynamic simulation to compare which variable is most appropriate?
Yes – a model with different variables can be used against the original model to compare variables. However, once variables have been changed, the simulation will need to be re-run in order to produce the results.
Find out what other questions were answered on the session, available on-demand now.
Does building construction and HVAC components need to be assigned prior to running CFD simulation?
A full energy simulation should be completed beforehand, which can then be imported into your CFD model to set the correct boundary conditions.
What kind of output is generated from an IESVE CFD simulation?
MicroFlo, our CFD application, does point-in-time CFD analysis of a single room, to produce a visual representation of the results as well as video representations of the airflows present.
What is the difference between MacroFlo and Microflo applications in IESVE?
MicroFlo is for the detailed analysis of airflows and thermal comfort properties of a single space, at a specific point in time. MacroFlo is used to simulate bulk airflows both between spaces and from the environment for applications such as operable windows, thermal chimneys, atria, and detailed infiltration analysis.
MacroFlo can be included as part of a dynamic annual simulation while MicroFlo is used to take a deeper look at a specific space under specified or imported boundary conditions.
Can I model and analyze flow with people located in the room?
Yes - people can be added as components to a model and be assigned with heat gain, moisture, and CO2 generation.
Can IESVE be used for data center CFD simulation?
Yes – server racks can be imported as components with heat gain assigned to them. Learn more about our data center solutions here.
Find out what other questions were answered on the session, available on-demand now.
Can units be changed from imperial to metric?
Yes, units can be set as either Metric (in meters), or Imperial (in feet and inches) displayed in either Decimal, Engineering or Architectural Style. The input units can be changed by selecting the appropriate unit type from the Input Units dropdown menu at the top right:
Find out more about Input Units here.
Are there step-by-step guides for creating a generic building?
Yes – you can find more on how to get started with IESVE on our On-Demand Learning platform. The On-Demand Learning provides Training videos to work through at your own pace, such as the recordings of this year’s Learning Academy. You can access our On-Demand Training here.
Contact our team for more information, or visit our website.
