You might try changing the air capacitance. See this object (I
believe new to V6):
ZoneCapacitanceMultiplier:ResearchSpecial,
10, !- Temperature Capacity Multiplier
10, !- Humidity Capacity Multiplier
1; !- Carbon Dioxide Capacity Multiplier
Or, if using a previous version, a different air heat balance
solution method (see documentation):
The default if this object is not present in the input file is
ThirdOrderBackwardDifference which may be susceptible to very small
simulation time steps (due to rapidly changing zone temp). You could
try a method which is less susceptible to variations in simulation
time step.
ZoneAirHeatBalanceAlgorithm, AnalyticalSolution;
or
ZoneAirHeatBalanceAlgorithm,EulerMethod;
On 11/17/2010 8:08 AM, cleef_lee wrote:
Hi,
I am using E+ with BCVTB to test heating control in domestic houses.
In order to validate the heating behaviour of a simple house with regular materials, I have built a simple 5m x 3m x 3m box house with an electric radiator (700W capacity) and no windows or doors or any kind of internal loads. The construction materials have values based on a BRE measured u-values report and more or less are average materials used in UK domestic houses.
I run the simulation in E+ for 5 days with outdoor temperature between
-4 and 9 degrees Celsius and the temperature graph was somehow weird. When the heating goes to ON the temperature initially increases rapidly (more than 1 degree per 3 minutes) and then increases with a slightly more expected way (1 degree per 20min). In a similar way when the heating gets to OFF the temperature initially decreases too quickly (1 degree in 3 minutes) and then the decrease rate gets a little bit smoother.
Do you have any idea why the temperature curve follows this positive or negative "logarithmic" form ?
Thank you very much!
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