I use the Air Source Heat Pump (ASHP) unit Type 119c in a
simulation of a container building in TRNSYS 18, since this
seems to be the only ASHP type available. I need to add the
two external .dat- files that contains the heating and cooling
performance data, respectively. I read in “09-Tutorials” page
163-164 that:
“The ASHP component model requires a data file that
includes the performance map for the piece of equipment.
This performance map is unique to the exact piece of
equipment that is being modeled and you will need to produce
this file from the manufacturer’s performance data for the
specific equipment being modeled.”
The component does not extrapolate
beyond the data range provided, so we need to include data
for outdoor temperatures between -5 °C and 40 °C (Shanghai
climate). The
indoor temperature is expected to be between -5 °C and 50
°C (due to that the heat pump
is turned off when no one is at home).
I
read “10.2.3.4 Resizing the PTHP Units” that says that the
recommended method is to find a manufacturer of PTHP units
online and to search through the available product
literature to find a PTHP that has a capacity as close as
possible without being less than the peak total cooling or
heating load required by the zone that will be conditioned
by the PTHP. Do someone know any such online source that
contain adequate information where I can search for a
similar product?
Or do you
recommend me to go for the second approach, to renormalize the
example files ASHP_Cooling.dat and ASHP_Heating.dat that comes
with TRNSYS to a different rated capacity? But my
highest “return air dry bulb temperature” and “Outdoor dry
bulb temperature” are far higher than in these example files,
so then I need to extrapolate the data. And how do I locate
the performance point in ASHP_Cooling.dat that corresponds
to the rated point, as described in
10.2.3.4?
I have
also tried to model with ideal heater and cooler and divide
the electric energy use for heating and cooling by their
respective seasonal COP, but that is not accurate enough
since I need to take into account the variation in COP over
the year.
The heat
pump that we have installed and want to model is GREE
KFR-35W/FNhD02-A1 outdoor unit (corresponding to indoor unit
model KFR-35GW/(35592)FNhAa-A1) which has the following
performance data:
- Cooling power (rated/min./max.): 3500/200/4200 W
- Heating power (rated/min./max.): 4900/500/5600 W
+1000 W (Additional electrical heating)
- Cooling input power (rated/min./max.): 840/90/1300
W
- Heating input power (rated/min./max.):
1450/120/1700 W
- Additional electrical heating input power: 1000 W
- Cooling seasonal COP: 5.33
- Heating seasonal COP: 3.53
- Yearly COP: 4.53
I tried to contact the manufacturer to get input data
for the files and sent them the instructions from “4
Mathematical Reference” page 174-175 “Data Files” and the
two example files ASHP_Cooling.dat and ASHP_Heating.dat
that comes with TRNSYS 18. The data they sent me, however,
was not for constant air flow rates. For instance, for
heating mode they sent me similar information as in the
table below for various temperatures. The problem is that
these data does not keep a set of fixed temperatures and
air flow rates, like in the example files.
|
indoor air
temperature |
outdoor air
temperature |
Total capacity (kJ/h) |
Power
consumption(kJ/h) |
Air Flow Rate(l/s) |
Return air dry
bulb(℃) |
|
30℃ |
28℃/RH50％ |
762 |
127 |
163 |
44.5 |
|
24℃/RH55％ |
706 |
128 |
163 |
43.3 |
|
20℃/RH59％ |
785 |
169 |
163 |
44.9 |
|
15℃/RH65％ |
992 |
284 |
161 |
49.2 |
|
11℃/RH75％ |
1078 |
362 |
160 |
51.2 |
|
7℃/RH85％ |
1085 |
418 |
160 |
51.3 |
|
2℃/RH85％ |
1063 |
485 |
159 |
51 |
Audun