IES-VE User Forum

1) To provide in/out flow of the room ( 133 CMH ) i have defined supply & extract grills instead of windows & doors in MicroFlo with 1m/s velocity.

2) Also i have assigned Heat flux of 6000 KW ( that includes roof solar load, lighting load, human load & Equipment load) in boundary conditions.

However below are the MicroFlo output results which clearly indicates there is an air movement.

1. LMA : minimum 0.7 minutes & Max 18 minutes.
2. Velocity : minimum 0.1 m/s & max 1 m/s.
3. Temperature : minimum 24 deg C & Maximum 80 deg C (its a casting shop)

I feel it is not required to define parameters in MacroFlo since i have assigned all the parameters in MicroFlo boundary conditions (as mentioned above in point #1 & 2).

From what I see, I think you haven't applied the gains to the zone before running apache sim. That is why the boundary condition file is showing the convective gains to be zero.

So when you import heat gains into MicroFlo, it imports the gains as 'zero'. Now when you apply the 6MW load into the rooms where MicroFlo knows to have 0 gains, it applies a opposing -6MW of cooling within the room to maintain balance. This -ve gain is causing the temperatures to be below your expectations.

To fix this, I would suggest running apache sim with all settings turned on - internal gains applied to the room and macroFlo openings properly defined. When you will import boundary conditions based on settings done as suggested, you will see the flow rates applied as per the results and the room gains showing up in the space as well. Just make sure you don't exceed the gains imported otherwise the artificial cooling will affect the results.

Or otherwise, ensure that you do not tick on import internal gains and import opening flows when you import boundary conditions. this will allow you to see full effect of any gains you apply in MicroFlo.

On another note, it would be better idea to apply the heat gains to the rooms in ApacheSim. This allows the surface temperatures to be more accurate and near the temperatures expected when exposed to gains of 6MW.