Michael,
The HEATING and COOLING types that are built into TRNBuild and
Type56 are primarily used for computing the idealized heating and
cooling loads of the space. Those loads can then be imposed on a
system but the performance of the system is then dependent only on
that load, not on the delivery temperature or the room temperature.
This method of calculating system energy use is called Energy Rate
Control. What you are aiming for in your simulation is something
called Temperature Level Control where a themostat senses room
temperatures and sends control signals to equipment. The equipment
provides flows of hot or cold water and air to the delivery devices
and the room temperatures react accordingly. The Type56 model is
computing an energy balance on the space that reacts to the delivery
devices. You need to get away from using the built-in idealized
HEATING inputs and towards defining the ventilation streams, active
layers, and energy gains that will cause the space temperature to go
up or down. There is a tutorial available that will step you through
the basic process of migrating from Energy Rate Control to
Temperature Level Control. Even though it does not directly apply to
your radiator system, I think it will help your understanding of the
underlying concepts.
http://sel.me.wisc.edu/trnsys/downloads/tutorials_and_examples/tlc_tutorial17.pdf
Best,
David
On 10/20/2012 08:43, Michael Diekerhof
wrote:
David,
Unfortunetaly I don´t have access to the TESS library. I´m sorry
but I dont understand what you were meaning with: "If you do
not, then I would imagine that you might be able to come up
with a simplified set of equations that would give you the
gains to the space that you need. "
Do you mean that I use the GAINS to adjust the radiative and
convective part ? But how to take the room temperature into
account by also considering the outlet temperature out of my
storage ?? Isn´t there also a way to work with HEATING INPUTS ?!
I still dont have an idea how to cover my heat demand by using
the outlet temperature :(
Best,
Michael
Am 19.10.2012 20:15, schrieb David BRADLEY:
Michael,
Ideally, you need a radiator model that will deal with the
water side, take room temperature from Type56 and output the
convective and radiative gains to the space as outputs. Such a
model exists in the TESS HVAC library for Trnsys17 if you have
access to it (Type1231). If you do not, then I would imagine
that you might be able to come up with a simplified set of
equations that would give you the gains to the space that you
need.
Best,
David
On 10/18/2012 09:24, Michael Diekerhof wrote:
David,
thanks a lot. I´ll have a look.
Could you please help me in another case. My plan is to
connect the HP to a storage tank and then giving a temperature
from the storage (type4) to my type56... How can I realize
that my type 56 can be heated to achieve a constant room
temperature of e.g. 20°C ?!
Someone told me that I must use HEATING and then INPUT... but
what if i would like to simulate a simple radiator with a
simple inlet temperature of e.g. 55°C.
Do you understand my problem? I dont know how to cover my heat
demand out of the storage.
Thanks in advance
Best,
Michael
Am 18.10.2012 16:16, schrieb David BRADLEY:
Michael,
I would recommend that you look online at manufacturer's
sites for similarly sized heat pumps. Trane and Carrier both
have significant amounts of performance data in the product
literature parts of their sites. You can probably get a good
estimate of the flow rates on both the condenser and
evaporator sizes from them.
Best,
david
On 10/18/2012 03:53, Michael Diekerhof wrote:
Dear all,
I´m working with the heat pump non-standard type 401 and
try to display an air-source heat pump.
I dont have typical values for the Input 2 (evaporator
mass flowrate) and Input 4 (condenser mass flowrate).
The only real connection I´m using is the dry bulb temp,
coming from type 15, as the evaporator inlet temperature.
For the massflowrates I would like to assume constant
values.
How can I adjust an outlet condenser temperature of e.g.
55°C. Just about the massflowrates ?!
Does anyone have experience with heat pump mass flow
rates?! I guess it´s not necessary to have expieriences
with Type 401.
I´m thankful for any advices.
Best,
Michael
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Am 18.10.2012 16:16, schrieb David BRADLEY:
Michael,
I would recommend that you look online at manufacturer's
sites for similarly sized heat pumps. Trane and Carrier both
have significant amounts of performance data in the product
literature parts of their sites. You can probably get a good
estimate of the flow rates on both the condenser and
evaporator sizes from them.
Best,
david
On 10/18/2012 03:53, Michael Diekerhof wrote:
Dear all,
I´m working with the heat pump non-standard type 401 and
try to display an air-source heat pump.
I dont have typical values for the Input 2 (evaporator
mass flowrate) and Input 4 (condenser mass flowrate).
The only real connection I´m using is the dry bulb temp,
coming from type 15, as the evaporator inlet temperature.
For the massflowrates I would like to assume constant
values.
How can I adjust an outlet condenser temperature of e.g.
55°C. Just about the massflowrates ?!
Does anyone have experience with heat pump mass flow
rates?! I guess it´s not necessary to have expieriences
with Type 401.
I´m thankful for any advices.
Best,
Michael
_______________________________________________
TRNSYS-users mailing list
TRNSYS-users@cae.wisc.edu
https://mailman.cae.wisc.edu/listinfo/trnsys-users
--
***************************
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
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