Christopher,

In terms of geometry, the input methodology has some good points, even if
it appears a bit clunky. The latest version 4.8 has some improvements. Ida
also has very good IFC import capability. I can usually re-use about 70%
from unaudited Revit models, more if the model is well constructed.
Sketchup can be input as well.

The user interface for generating building models is friendly and
uncluttered. IDA rarely get's a "facelift". This is a good thing - it's
evolving. It still uses the floppy disk icon! It handles data predictably
and robustly without any "volatile" relationships between data inputs. The
underlying component models can be accessed if using the expert version
(i.e. the maths that describe objects such as zones, coil's, boreholes,
etc). There's a schematic modelling interface enabling the user to build
sub-system models and hack into details in larger building models. It has
an ice rink and swimming pool module. I understand this was used for
calculations on the ice making facility at the new Stadium in Stockholm
(they can ice the whole pitch!). There is a 90.1 tool available.

The thing that really is unique to IDA is that it simulates plant, controls
and network airflow in a very integrated way. In fact, these three aspects
are permanently coupled. They cannot be uncoupled. This makes for a very
robust analysis. The nearest example I can think of that compares is
simulating IES with ApacheHVAC and Macroflo activated. This can quantify
air movement under both natural and mechanical ventilation combined. A
direct comparison with other software cannot be made though. Some quite
arbitarily complex systems can be made. For example, mixed mode systems
with lockout's between the VAV boxes and actuated louvres, unusual SAT
reset strategies, dual duct systems. These all simulate the coupled
controls + network aiflow + plant in a very stable manner. You don't need
to make the timestep very small to make the simulation very stable, because
the timestep varies dynamically during runtime seeking the most stable
computational solution. Waterside modelling is a bit harder but can be done
with a bit of practice.

I could go on, but it's getting late.

Chris

Hello there,

I started using IDA ICE for my master thesis two years ago, for which I
had to model a complex HVAC system for a museum (several ventilation
systems for cooling/heating+drying/humidifying with 2 central heat
recovery systems, rooms with contaminated air, different control
strategies with variable airflows...) Though the whole system became
quite complex in the end it was still possible to keep on working well
with the models and optimizing the control strategies using the features
of the integrated model versions comparator.

As Chris Yates already explained, it is possible to get into the
mathematical background of every components of the model. You can also
plot every variable that you find there, so you can really interrogate
what happens in the model.

Furthermore there are some great other tools like loading different
models and getting a "difference check", which is pretty useful while
debugging, or also starting an additional session with an independent
Core, so you can keep on working on an other model while already running
another simulation.

The results can be well exported and in different ways if needed.

Regarding the geometry I found the combination of the 3D interface with
the floor plan interface quite good. Importing schemes from IFC,
Sketchup or DWG worked well too.

Important to mention as well is the help from EQUA: mail, phone,
webinars (free), seminars (not free), also the users forum can be very
useful. Since I have been using IDA ICE I could always find a way to
solve the problems (debugging or modelling).

As a user I find it also great that there are so many possibilities to
explore, so many things to model, to connect and to simulate, you have
the feeling you are learning a lot while working, but this is something
which is common to any good software...

Last but not least: there is an integration of OpenFOAM which is
coming,... currently it is still a beta-version but I already saw it
working, quite impressive.

I don't have that much experience with other softwares so I can not
really compare objectively. I can only say: go for a trial or/and ask
for a live-demo and judge by yourself!

Greetings from Berlin

C.L.

Am 23.02.18 um 14:24 schrieb Jones, Christopher via Bldg-sim: