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Re: [TRNSYS-users] Changing thermal capacity of type 56 DURING a simulation?
Jochen,
I do not think that there is a way of changing the zone capacitance
during a simulation. There is a model for a lumped capacitance in the
TESS Loads and Structures library that could be a starting point model
for writing your own model of the product being stored. Two challenges
occur to me though: first, I would be surprised if you could model the
stored product with the "lumped capacitance" assumption. That assumption
basically means that there is no temperature gradient within the product
(that its internal thermal conductivity is high in comparison to its
surface heat transfer). Second, it also assumes that the capacitance
does not change. I think the only really correct solution would be to
solve the differential equation (including the change in mass (dm/dt)
and then code it as a Type. Type56 would pass it the surrounding zone
air temperature and your model would compute the amount of energy
transferred to/from the zone, passing that back as an input to Type56.
Best,
David
On 1/4/2012 05:58, Jochen Doell wrote:
Dear TRNSYS-developpers & users,
is there a way to change the thermal capacity of type 56 DURING a
simulation?
We need to simulate a storage room which can be filled at different
levels.
We already thought about an external calculation but would prefer
easier methods if available.
Best regards (and happy new year, for the very late risers),
Jochen
--
***************************
David BRADLEY
Principal
Thermal Energy Systems Specialists, LLC
22 North Carroll Street - suite 370
Madison, WI 53703 USA
P:+1.608.274.2577
F:+1.608.278.1475
d.bradley@tess-inc.com
http://www.tess-inc.com
http://www.trnsys.com