44
IDA Indoor Climate and Energy 4.5
© EQUA Simulation AB 2013
81
threshold value are shown and the scale bar is red above and blue below the threshold
value. The threshold value can be dragged while holding down the Ctrl-key. Ctrl-click
somewhere outside of the scale bar to show the regular scale bar.
When visualizing a parameter with a finite number of options you can Ctrl-click on the
different categories in the same way.
Visualizing sun path and shading over time
Click Animation button: Opens the Show animated results dialog. In the Show animated
results dialog, check Show shadows and click Show.
An animation starts with shadows, following the sun path of the day, displayed on
the 3D model.
Pause the animation: Click the Play/Pause button
Start the animation: Click the Play/Pause button
a second time.
Speed up/slow down the animation: Change the Tplay value (the time it takes to
animate 24 hours of simulation).
Jump forward/backward in the animation: Use the scroll bar, or change the
simulation time value.
Close the animation: Use the Close button
. Alternatively Press H or Right mouse
button menu -> Hide animation.
7.2.4.3. Incorporating CAD objects and images
Inserting CAD objects and images
Insert -> Import CAD: Opens the Import CAD dialog. In the Import CAD dialog, select
file and click Open. Alternatively click Import… button -> CAD and vector
graphic/Bitmap or IFC… button -> Import… on the Floor plan tab.
The CAD object/image is shown in the 3D view and a section of it is shown on the
floor plan tab.
The CAD object/image is inserted with respect to the building coordinate system, i.e.
it will move with the building when the building is repositioned.
Move and change size of the CAD object/image by dragging it/resizing it in floor
plan or editing the parameters in the dialog shown when object is double-clicked.
Include the object (not image files) in the shadow calculation and visualization:
Check the Calculate shadows checkbox in the dialog shown when object is double-
clicked.
By default CAD objects are save in the system file (*.idm) so that the original CAD
file does not need to be saved. If the CAD file is big, the option of not saving it in
the system file will be given. This will speed up the performance of IDA ICE, but
the original CAD file needs to be saved.
Tip: To place a CAD object/image at the current mouse pointer, use Right mouse button
menu -> Import CAD
Inserting CAD objects and images to site
46
IDA Indoor Climate and Energy 4.5
© EQUA Simulation AB 2013
82
Insert -> Import CAD to site: Opens the Import CAD dialog. In the Import CAD dialog,
select file and click Open. Alternatively click Import site CAD button on the Site object
dialog open by clicking Site shading and orientation on the General tab.
The CAD object/image is shown in the 3D view and in the Site object dialog.
The CAD object/image is inserted with respect to the site coordinate system, i.e. it
will not move with the building when the building is repositioned.
Move and change size of the CAD object/image by dragging it/resizing it in the Site
object dialog or editing the parameters in the dialog shown when object is double-
clicked.
Include the object (not image files) in the shadow calculation and visualization
Check the Calculate shadows checkbox in the dialog shown when object is double-
clicked.
By default CAD objects are save in the system file (*.idm) so that the original CAD
file does not need to be saved. If the CAD file is big, the option of not saving it in
the system file will be given. This will speed up the performance of IDA ICE, but
the original CAD file needs to be saved.
Tip: To place a CAD object/image at the current mouse pointer, use Right mouse button
menu -> Import CAD to site
Supported file formats
BIM
IFC (*.ifc)
CAD and vector graphic files
AutoCAD (*.dwg, *.dxf, *.dwf)
IDA ICE supports DWG file formats up to AutoCAD 2004. DWG files of
unsupported formats can be converted with the free tool Autodesk DWG
TrueView.
DWG files are assumed to be two-dimensional, i.e. any 3D geometry is flattened
to 2D at import.
SketchUp (*.skp)
3D Studio (*.3ds)
Wavefront (*.obj)
Computer Graphics Metafile (*.cgm)
Corel Presentation Exchange (*.cmx)
MicroStation DGN (*.dgn)
Micrografx DRW (*.drw)
Gerber File Format (*.gbr)
Scalable Vector Graphics (*.svg)
Printer Command Language (*.pcl, *.prn, *.prt)
Macintosh PICT (*.pct)
HP-GL/HP-GL2 (*.plt)
WordPerfect Graphics (*.wpg, *.vwpg)
Image files
Bitmap (*.bmp)
28
IDA Indoor Climate and Energy 4.5
© EQUA Simulation AB 2013
83
JPEG Interchange Format (*.jpeg,*jpg)
Portable Networks Graphics (*.png)
ZSoft PC Paint (*.pcx)
Tagged Image File Format (*.tiff,*.tif)
Adobe Photoshop (*.psd)
Truevision (*.tga)
Windows Meta File (*.emf,*.wmf)
7.2.5. Simulation tab
7.2.5.1. Simulation tab
Requested output
Click Select to see and/or specify what diagrams and reports that will be created during
the simulation.
Heating load
See Heat Load Calculation and Results in ICE Getting Started manual
Cooling load
See Cooling Load Calculation and Results in ICE Getting Started manual
Energy
See Energy Calculation in ICE Getting Started manual
Custom
Open Simulation data dialog to select simulation times and tolerances, etc.
Advanced level
Click Build Model to (re)build the mathematical model of the system.
Click Edit to switch to the schematic view of the system.
After a simulation, the result diagrams and reports chosen can be found under the Results tab
(see Dialog for choice of output).
19
IDA Indoor Climate and Energy 4.5
© EQUA Simulation AB 2013
84
7.2.6. Dialog for choice of output
Output from a simulation is presented as diagrams and reports. There are several different
diagrams to choose from. The selection is made from the Choice of output dialog that is
accessed by clicking on the Requested output button in the building form or if Choose output
is selected in the Tools menu. The following diagram and reports exist (those marked with #
are pre-selected but can be deleted):
Diagrams
Building level:
AHU temperatures(#) Air temperatures in central AHU
AHU airflows Air flows through central AHU
Plant temperatures Plant temperatures: Boiler & chiller, in & out
Total heating and cooling (#) Heat and cooling supplied by plant and ideal room units
Plant details
Detailed measures from an ESBO plant model.
Zone level:
Main temperatures(#) Air and operative temperatures
36
IDA Indoor Climate and Energy 4.5
© EQUA Simulation AB 2013
85
Heat balance Detailed heat balance for zone
Air temperatures at floor and ceiling Air temperatures at floor and ceiling in case of
displacement ventilation.
Fanger’s comfort indices Fanger's comfort indices, PPD, PMV
Indoor Air Quality Indoor air quality measures: Ac/h, CO2 level, humidity
Daylighting Daylight level at desktop (1st person)
Directed operative temperatures
Air flow in zone Air flows in zone, in/out through internal/external walls or
mechanical ventilation
Airborne heat flow into zone Airborne net heat flows into zone, through internal walls,
envelope and mechanical ventilation
Surface temperatures Temperatures of zone surfaces
Surface heat fluxes Convective and long wave radiative heat flux of zone surfaces
Reports
Building level:
Delivered energy Totals of energy, purchased or locally generated, including cost,
CO2 and primary energy
Time series of underlying measurements can be logged by logging sources
Systems energy Overview of energy transferred by HVAC systems
Lost work Account of work hours lost due to over or under heating
AHU energy Energy transferred by individual Air Handling Units
Time series of underlying measurements can be logged by logging sources
Zone level:
Energy Zone sensible energy balance
Time series of underlying measurements can be logged by logging sources
Thermal comfort according to standard EN-15251
7.2.6.1. Heat Load Calculation
See Heat Load Calculation and Results in ICE Getting Started manual.
7.2.6.2. Cooling Load Calculation
See Cooling Load Calculation and Results in ICE Getting Started manual.
7.2.6.3. Energy Calculation
See Energy Calculation in ICE Getting Started manual.
7.2.6.4. Choice of Simulation data
C# TIFF: C#.NET Code to Convert JPEG Images to TIFF XDoc.Tiff for .NET, which can be stably integrated into C#.NET string[] imagePaths = { @"C:\demo1.jpg", @"C:\demo2.jpg", @"C:\demo3.jpg" }; // Construct List
convert multiple pdf to jpg online; changing pdf to jpg on
18
IDA Indoor Climate and Energy 4.5
© EQUA Simulation AB 2013
86
The simulation data object is used to define Custom simulations and to change solver
parameters for all types of simulations. Custom simulations should be defined when any of
the pre defined standard simulations Heating, Cooling or Energy are inappropriate, for
example when only a month should be simulated.
In the Calculation tab, select between a periodic and a dynamic simulation. A periodic
simulation means a certain period is simulated a number of times until the system has
stabilized and no longer changes from simulation to simulation (a periodic state).
A dynamic simulation means that the simulation starts at a particular time and ends at another
time. Both these times are indicated in the same way as the date for periodic simulation. How
the simulation is to be initialized must also be indicated for a dynamic simulation. For this
reason, another tab, named Startup, is added to the Simulation data dialog.
The startup phase can also be periodic or dynamic. Make the selection in the same way as
above. A periodic startup phase means that the selected period is simulated a number of times
until the system has stabilized. A dynamic startup phase means that a selected number of days
are simulated before the proper simulation starts.
31
IDA Indoor Climate and Energy 4.5
© EQUA Simulation AB 2013
87
How long the startup phase should be depends on how heavy the building is and on its contact
with the ground. The heavier the building, the longer startup phase is required. Approximately
two weeks should however always be enough for most buildings. In both cases, no
intermediate results are saved from the startup phase.
Integration parameters can be selected under the Advanced Tab in the dialog. See also the
manual for description of these parameters.
Field descriptions, etc:
Tolerance This number determines how accurately equations are to be solved (-)
Maximal timestep The largest timestep to be taken (h)
Maximum number of periods Maximum number of periods in a periodic simulation.
Tolerance for periodicity Tolerance for periodicity in a periodic simulation (-)
The tolerance given is the degree of accuracy reached in the calculated variables. It is absolute
for small quantities (normally < 1) and relative for larger quantities (normally >1). The
precise definition of Tolerance is given in the documentation for IDA Solver, which can be
obtained from EQUA. Relaxing the tolerance should normally result in a faster simulation.
However, if the tolerance is relaxed too much, the solver will have greater trouble to find a
solution at all and this in turn costs execution time and causes poorer stability.
Output step If greater than zero, recorded times in output files will have this time step (h).
If a Time step for output has been given, result files will be interpolated to have a fixed time
step, enabling for example Excel comparison of results between different runs. Simulation
time step is still variable.
If a Time step for output is zero (or left blank), the time step of output will be same as solver
timesteps, i.e. not equidistant in time.
Note that result files will contain instantaneous values of measured variables, i.e. not integrated values over the given step.
In order to obtain average, e.g. hourly, results use Table tab of result diagrams instead.
For a dynamic simulation, the solver will select the time step up to the Maximal timestep
specified. Allowing very long timesteps may create stability problems for the solver that in
turn cost time to resolve.
31
IDA Indoor Climate and Energy 4.5
© EQUA Simulation AB 2013
88
In the case of a periodic simulation, the number of periods can be limited and a tolerance
chosen for the relative changes required from day to day, for the simulation to be considered
periodic.
See also Topic note on timesteps at the ICE User Support web page (Help menu).
7.2.7. Results tab
7.2.7.1. Simulation Results
The Results tab is shown automatically, after a completed simulation.
Field description:
Summary of scalar results
Three tables: Summary, Heating design and Cooling design, that present key scalar
results on a zone-by-zone basis. Heating and cooling design will always present
information from the corresponding special simulation done. The Summary table will
always show results from the last simulation done, i.e. this could have been a heating,
cooling, energy or custom simulation. Heating and cooling results will be retained until
that particular simulation is repeated, i.e. they will not be overwritten by, e.g., an energy
simulation.
Scalar results often represent maximum values of various sensor readings. Note that by
default signals are filtered by a 15 minute sliding average (time can be changed in System
parameters). This is because very sharp peak values, spikes, often convey insignificant
information that depends on approximations made rather than on underlying physics.
This also means that presented results may not always correspond with a manual reading
from a diagram.
Study the tooltip texts (also presented in the status bar) of each signal for more precise
information.
Modified
The time when the model was last changed. Only shown if the model was changed after
the latest simulation.
Saved
20
IDA Indoor Climate and Energy 4.5
© EQUA Simulation AB 2013
89
The time when the case was last saved on disk.
Simulated
The time when the latest simulations were run.
Sim. type
The type of the last simulation.
Make report
When pressed, the results are combined into a single Word document. Implemented for
Word 2000 or later.
Detailed result
A list of all result objects requested before the simulation.
More…
Access to further reports, e.g. Multizone report – the equivalent of the zone Energy report
– but applied to an arbitrary collection of zones – or Compare results – a way of
comparing multiple separate cases in the same report.
7.3. HVAC Systems
7.3.1. The Primary system
For documentation, see the section on Primary system in the manual.
12
IDA Indoor Climate and Energy 4.5
© EQUA Simulation AB 2013
90
7.3.2. Air handling unit
Read about the Air handling unit in the manual.
7.3.3. Form for Heating Coil
The figure illustrates the form used for an object of the Heating Coil type. A heating coil is
one of the parts in the air handling unit. The form is most easily opened by double clicking on
the symbol for heating coil (hc) in the air handling unit’s Schema.
Field description, etc:
ETAAIR Air side effectiveness at capacity (-)
DTLIQ Liquid side temperature drop (°C)
Documents you may be interested
Documents you may be interested
