Re: [EnergyPlus_Support] Dx coil single speed control

["Jean Marais jeannieboef@xxxxxxxxx [EnergyPlus_Support]" <EnergyPlus_Support@xxxxxxxxxxxxxxx>]

This is where real life and simulation diverge. I'll ask you this: if there was a air bypass of the coil, what would it mean for your building energy usage as appossed to if there was no bypass? E+ does not compute hydraulics (pressure loss over the coil...this may have changed with the general coil model in v8.7, ive not checkd). So dx models are performamce metric based. That is, the program has certain setpoints that it is trying to achieve like outlet air temperature, humidity, total airflow, fresh air rates. It will adjust the airflow through the coil within the bounds set or calculated to best match the needed outlet conditions. The model knows what the entering fluid of the coil is for a given set of conditions such at outdoor drybulb, etc. Because it has the information of how much energy is taken from the air for all possible conditions, and what the sensible heat ratios are for any, it easily calculates the exiting air conditions.

If you have a bypass for your dx unit, I think the DUCT object is what you need to include.

Am 15.04.2017 10:18 nachm. schrieb "alyelhefni@xxxxxxxxx [EnergyPlus_Support]" <EnergyPlus_Support@xxxxxxxxxxxxxxx>:

 

Hi all,

I have a single speed dx coil with a setpoint defined. The coil is part of a 100% outdoor air constant volume.

When viewing the simulation results, the coil suceeds achieving the output setpoint in full and part loads.

The question is how does dx single speed cooling coil run at part loads and how does it do that o energyplus? Is the coil partially or fully bypassed from air stream? 

__._,_.___

---

Posted by: Jean Marais <jeannieboef@xxxxxxxxx>

---

EnergyPlus support is found at:
http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx

The EnergyPlus web site is found at:
http://www.energyplus.net/

The group web site is:
http://groups.yahoo.com/group/EnergyPlus_Support/

Attachments are currently allowed but be mindful that not everyone has a high speed connection.  Limit attachments to small files.

EnergyPlus Documentation is searchable.  Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.

Visit Your Group

• New Members 4

• Privacy • Unsubscribe • Terms of Use

__,_._,___