Hi everyone,
I am using
Type534 with Plug-in, inserting 1 port and 1 miscellaneous
heat flow to it. My
doubt is about temperature stratification in the tank. Even
if I increase the
number of nodes, the temperature difference between the node
where I insert the
heat flow and the rest of the nodes is too large, i.e. the
nodes without external heating barely warm up.
It also happens even if I remove the port
and, consequently, simulate it as a tank without any inlet
or outlet: the lower
nodes barely increase their temperature (I want the
miscellaneous heat flow in
node 1 or 2), no matter the time length I run the
simulation... The upper nodes
do reach the desired temperature (I have a controller to the
heater that is connected
to miscellaneous heat flow for that) but the lower nodes
remain almost at
constant temperature. I tried to change the “inversion
mixing flow rate” to
both high and low values, negative and positive values,
zero… but the changes
in T of the nodes are not visible. I want to increase T of
water in tank from
20ºC to 150ºC and I have a quite high water draw from the
tank, thus I don’t want
that only one or two nodes reach 150ºC, but I want most or
all of the tank to do so instead… no
matter how much time it takes to heat it up.
How to make the lower nodes to heat up? Which other
parameter can I change so the stratification in the tank
really works? Is there
any other parameter to change rather than “inversion mixing
flow rate” to get
normal stratification? Should I use another type?
Thank you very
much in advance.
Alaia Sola Saura
Project engineer
Thermal Energy
and Building Performance Group
IREC
Institut de Recerca en Energia
de
Catalunya
www.irec.cat