[TRNSYS-users] type107 or 680 data file

[Mario Leroy Ortiz]

Jochen,

What I did to create the .dat file is as follows:

I used your algorithm.

I calculated the 'cooling required' for the rated 5.5 C
temperature change.  The spreadsheet says 70.287 kW but
I could have just used the stated capacity of 70.3 kW.

Then I calculated the 'available cooling capacity' given
hot, cool and chilled water inlet temperatures.  I 
followed
the Yazaki cooling capacity formula and multiplied rated
capacity by heat flow correction and cooling capacity
factor.

Then I divided 'cooling required' by 'available cooling
capacity' to get the capacity fraction.  This value is
the fraction that runs down the left side of the page
starting at the 5th line of the .dat file.  I did this
for different inlet hot and cool water temperature.
(The column G label in the spread sheet should say
cooling available.)

To calculate the design energy input fraction, I
first used the Yazaki heat input equation to calculate 
'required
heat' given operating conditions.  I multiplied the 'rated
heat input' by heat flow correction and heat input factor.

I divided 'required heat' by the 'rated heat input' to 
calculate
the design energy input fraction.  This is the second 
column of
numbers that run down the left side of the .dat file.

Let me reference the comment "fraction of design load" 
from the
.dat file.  This is the line that has 1.0 and 0.8.  The
fractions calculated in the previous paragraphs are for 
the fraction
of design load of 1.0 (full load).  The capacity fraction 
is the
same for 1.0 and 0.8.  The design energy input fraction 
for 0.8
is the the design energy input fraction for 1.0 multiplied 
by 0.8.
I suppose this represents the case where only 80% of the 
rated
delta T is required so 80% of the heat is need to remove 
it.
By inspecting the example .dat file is where I figured out 
how
to get the different fraction of design loads from the 
calculated
data at 1.0.  It seems to be the pattern.  I must state 
that
I did not test any TRNSYS output below full load 
capacity,,, yet.

So that s what I did.  I have had no complaints.  About 7 
or 8
people all over the world have the files.

Now differentiating between "fraction of design load" and
"fraction of full load capacity".

There is a fraction of design load comment in the .dat 
file as
described above.  I take this to mean the required heat 
input divided
by available heat input.

To confuse matters, in the documentation for type 680 
there is a
symbol f^designload where f^designload = Q^remove / 
capacity^rated.
This formula is similar or the same as the formula used
to calculate the capacity fraction above.

Then there is fraction of full load capacity in the 
documention
represented by f^fullloadcapacity.  I am going to take a 
guess
and say that that represents the fraction of design load 
in the
.dat file.

How do you like that a full circle of confusion.  Terms in 
the .dat
file seem to be mixed up.  Either that or I am mixed up. 
 Probably
both and more so the later.

Like I said.  The tests I ran for 9 operating conditions 
at full
load match hand calculations of delta T within the range 
of 0.03 oC.
That where I am at.

Thank you,

Mario Ortiz




On Mon, 28 Jul 2008 09:21:36 +0200
  Jochen Doell <jochen.doell at ise.fraunhofer.de> wrote:
> Dear Mario,
> 
> thank You for Your .dat files on the SH20.
> I experience all the same trouble with ANY manufacturer. 
>My opinion is that they just underestimate the 
>possibilities (and the necessity) of accurate simulation 
>before installing a system.
> 
> Anyway, can You explain to me how You set up the data 
>file? I had problems with the definition of the 
>parameters, especially the difference between "fraction 
>of design load" and "fraction of full load capacity" is 
>not clear to me.
> 
>Following I added the question I sent to the user forum 
>(including an example). Maybe You can give a brief 
>answer.
> 
> Best regards,
> Jochen
> 
> 
>> Dear TRNSYS users,
>>
>> I have problems setting up the input file required by 
>>type 107 from
>> manufacturers data.
>>
>> To make this easier I would like to ask You to look up 
>>the following
>> example and correct it if necessary:
>>
>> I have a chiller with
>> Rated capacity = 35kW
>> Rated Energy Input = 50,2kW
>>
>>
>> One exemplary operation point:
>> T_hot_in=70°C
>> T_medium_in=27°C
>> T_cold_setpoint=7°C
>> P_hot_in=20,3kW
>> P_cold_out=13,5kW
>>
>>
>> Calculated fraction of design load:
>> f_design_load=(m_cold*cp_cold*(T_cold_in-T_cold_setpoint)/Capacity_rated
>>                          =(1,53kg/s*4,20kWs/kgK*2,1K)/(35kW)
>>                          =0,386
>>
>> Calculated fraction of full load capacity:
>> F_full_load_capacity=13,5kW/35kW=0,386
>>
>> Calculated fraction of design energy input:
>> F_design_energy_input=20,3kW/50,2kW=0,404
>>
>>
>> The following numbers would form one row in the input 
>>file.
>> T_hot_in=70°C
>> T_medium_in=27°C
>> T_cold_setpoint=7°C
>> f_design_load=0,386
>> F_full_load_capacity=0,386
>> F_design_energy_input=0,404
>>
>> I doubt that the "fraction of design load" and "fraction 
>>of full load
>> capacity" should be the same....
>> So what is the difference between the two. If the latter 
>>is the maximum
>> chilling capacity I could get from the machine (what I 
>>suppose right
>> now) how is it defined? As far as I know manufacturers 
>>do not deliver
>> that number... 
> 
> 
> Mario Leroy Ortiz schrieb:
>> Absorption Chiller Users,
>>
>> I have not recieved and data from Yazaki.  It has
>> been about 2 or 3 weeks since I asked for it.  We should
>> have asked for it before we paid them.
>>
>> Either way.  I think I have created a few absorption 
>>chiller
>> data files that model the Yazaki SH20.  I am getting 
>>TRNSYS
>> to output changes in temperature for hot and chilled 
>>water
>> flows very close to the tempertures changes calcultated 
>>by
>> hand calculations like the examples on the yazaki web 
>>site.
>>
>> Attached are 4 .dat files a TRNSYS project file and an 
>>Xcell
>> spread sheet.  The 4 .dat files are for 100%, 120%, 65% 
>>and 55%
>> of rated flow.  The project file is what I used to test 
>>the output.
>>
>> In the spread sheet, the left side of the sheet is where 
>>I calculated
>> the fractions and the right side is where I compared 
>>hand calculations
>> to TRNSYS results.  I was very surprised that they are 
>>so close after
>> I was so confused trying to create the data files.
>>
>> The data files are for the range of temperatures given 
>>in the Yazaki
>> website.  To give TRNSYS some data to work with I put 
>>data in each
>> .dat file for a chilled water set temperatures of 7 C 
>>and 7.1 C.
>> However, the 7.1 C data is simply the 7 C data repeated. 
>>I got that
>> idea from Sebastien.
>>
>> I did not get to try your new type Sebastien.  I do not 
>>know what to
>> do with the files you gave me in order to get an 
>>instance of the new
>> type into a project.  One day I ll figure it out.
>>
>> Hope this helps.
>>
>> Mario Ortiz
> 
> -- 
> _________________________________________________
> 
> Dipl.-Ing. (FH) Jochen Döll
> Dept. Thermal Systems and Buildings
> 
>Fraunhofer-Institut für Solare Energiesysteme ISE
> Heidenhofstrasse 2, 79110 Freiburg, Germany
> 
> Phone:	+49 (761) 4588-5527
>Fax:	+49 (761) 4588-9000
> Mail:	jochen.doell at ise.fraunhofer.de
> Web:	www.ise.fraunhofer.de
> _________________________________________________
>