You might want to try the QuickSim approach. It is currently an option to do preliminary analysis for COM Check and CBECC-COm. Here is the report on the approach
http://www.pnl.gov/main/publications/external/technical_reports/PNNL-19961.pdf
Jason
I know, but as the evolutionary solver proceeds not by exact simulation results but comparative data (which building alternative is better that which one), I probably can to make such a simplification. especially when considering that tens of thousands of alternatives are to be generated. once the optimal solution(s) are reached, precision calculations can be made...
of course, one alternative is to split the original model's calculation up into multiple threads, but that is my last resort :-)
On Wed, Jan 28, 2015 at 6:32 PM, 'Dr Yi Zhang' yi@xxxxxxxxxx [EnergyPlus_Support] <EnergyPlus_Support@xxxxxxxxxxxxxxx> wrote:
Just beware that you are trading accuracy for speed. The alternative solution would be� get a faster computer! J
Yi
Dr Yi Zhang, PhD CEng MCIBSE MASHRAE
Director
Energy Simulation Solutions Ltd. (UK)
From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx]
Sent: 28 January 2015 14:44
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: Re: [EnergyPlus_Support] simulation settings to shorten the run time
I actually am calculating the yearly energy use now, instead of the 4 dates that I mentioned above. So need to change some more settings. The ones I tried are:
1. changing the timestep from 2 to 1
2. max. HVAC iterations is reduced from 20 to 5 (but did not make much difference)
3. minimum system timestep is 0, instead of 1
So instead of shading with fins, I might use overhangs. Also the zone schedules might make a difference maybe, but I havent tried anything yet. Any ideas??
On Wed, Jan 28, 2015 at 4:39 PM, dru.crawley@xxxxxxxxxxx [EnergyPlus_Support] <EnergyPlus_Support@xxxxxxxxxxxxxxx> wrote:
Those 4 months may not be the peak months for temps or solar. The design data provided with most weather files (.DDY) includes the hottest and coldest month � the months used for the design conditions are the hottest and coldest:
! Washington Dc Dulles IntL Ar_VA_USA Annual Heating 99.6%, MaxDB=-11.8°C
SizingPeriod:DesignDay,
Washington Dc Dulles IntL Ar Ann Htg 99.6% Condns DB, !- Name
1, !- Month
21, !- Day of Month
�.
! Washington Dc Dulles IntL Ar Annual Cooling Design Conditions Wind Speed=4m/s Wind Dir=290
! Hottest Month=JUL
! Washington Dc Dulles IntL Ar_VA_USA Annual Cooling (DB=>MWB) .4%, MaxDB=34.1°C MWB=23.9°C
SizingPeriod:DesignDay,
Washington Dc Dulles IntL Ar Ann Clg .4% Condns DB=>MWB, !- Name
7, !- Month
21, !- Day of Month
�.
You can find the hottest and coldest month in the CSV file included with the install: C:\EnergyPlusV8-2-0\PreProcess\WeatherConverter\ ASHRAE_2013_Yearly_DesignConditions.csv (these are the same data as the 2013 ASHRAE Fundamentals Chapter 14 Climatic Data Information).
Column N has the ‘ColdestMonth’ and column AD has the ‘HottestMonth’.
From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx]
Sent: Wednesday, January 28, 2015 9:00 AM
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: Re: [EnergyPlus_Support] simulation settings to shorten the run time
Create 4 different RunPeriods, one for each of the days you mention - something like this:
On Sat, Jan 24, 2015 at 7:13 AM, ipekgursel@xxxxxxxxx [EnergyPlus_Support] <EnergyPlus_Support@xxxxxxxxxxxxxxx> wrote:
Hi,
I am linking EnergyPlus (and Radiance) to an evolutionary optimization tool that I am developing. To be able to generate and evaluate many design alternatives, I need to significantly shorten the simulation run time. The 4 calculations I am doing are heating load (21 dec.), cooling load (21 june), and lighting load (21 mar and 23 sep). what are the simulation settings that I can change?
I already simplified the model as much as I can. My question is only about the simulation...
thanks in advance!!!
--
James V Dirkes II, PE, BEMP, LEED AP
CEO/President
The Building Performance Team Inc.
1631 Acacia Dr, GR, Mi 49504
Direct: 616.450.8653
jim@xxxxxxxxxxxxxxxxxxxxxxxxxxx
Website l LinkedInThe truth is like a lion; you don’t have to defend it. Let it loose; it will defend itself.
-- Jason Glazer, P.E., GARD Analytics, 90.1 ECB chair Admin for onebuilding.org building performance mailing lists
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Posted by: Jason Glazer <jglazer@xxxxxxxx>
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