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Hello everyone,
I am currently developing a TRNSYS model of a solar-assisted cooling system that integrates a single-effect absorption chiller, solar thermal collectors.
For the absorption chiller, I am using Type 107. However, I have encountered an important issue regarding the default performance data file.
The default Type 107 data file in my TRNSYS installation uses the following inlet hot-water temperatures:
108.89, 111.67, 113.89, 115.00, and 116.11 °C.
My system, however, is designed to operate a low-temperature single-effect absorption chiller with a hot-water inlet temperature around 85–95 °C.
Therefore, using the default Type 107 performance file would place the chiller outside the temperature range of the original performance map.
I understand that simply replacing the hot-water temperature values in the default data file, for example changing them to 75, 80, 85, 90, and 95 °C, while keeping the original capacity and energy-input fractions unchanged, would not represent a physically valid chiller model.
I also found the following TESS/Yazaki data file:
Yazaki20-50ton(OneStage)S3.dat
which provides the relationship between inlet hot-water temperature and fraction of nominal cooling capacity:
76.67 °C → 0.00
79.44 °C → 0.25
82.22 °C → 0.47
85.00 °C → 0.63
87.78 °C → 0.82
90.56 °C → 0.97
93.33 °C → 1.06
96.11 °C → 1.13
98.89 °C → 1.22
This information is very useful for defining the effect of hot-water inlet temperature on cooling capacity. However, it appears to be insufficient for constructing the complete Type 107 performance data file.
As I understand it, the Type 107 data file also accounts for:
fraction of design load,
chilled-water setpoint,
entering cooling-water temperature,
inlet hot-water temperature,
and requires both:
capacity fraction, and
design energy input fraction.
The main difficulty is that publicly available manufacturer catalogues for low-temperature single-effect absorption chillers usually provide only nominal operating conditions or a limited number of correction curves. Complete multidimensional performance data are rarely available.
My required nominal cooling capacity is approximately 113 kW (about 32 TR), and the intended hot-water operating range is approximately 80–95 °C.
I would therefore appreciate guidance from experienced TRNSYS users or developers on the following questions:
What is the recommended method for creating a new Type 107 performance data file for a low-temperature hot-water-driven absorption chiller?
Are there existing Type 107 or TESS data files for single-effect absorption chillers operating in approximately the 75–95 °C range?
Does anyone have the corresponding Yazaki S1 and S2 data files associated with Yazaki20-50ton(OneStage)S3.dat?
If only the hot-water capacity correction curve is available from the manufacturer, is it acceptable to combine this manufacturer-specific relationship with normalized part-load, chilled-water-temperature, and cooling-water-temperature relationships from another validated absorption-chiller dataset?
How should the Design Energy Input Fraction be determined when the manufacturer provides cooling-capacity correction factors but does not provide detailed heat-input or COP data for all operating conditions?
Would another TRNSYS/TESS absorption-chiller component be more appropriate than Type 107 for modeling a solar-driven single-effect chiller operating around 85–95 °C?
If manufacturer selection software can provide several off-design operating points, would it be acceptable to use those data to construct the multidimensional performance map required by Type 107?
My main objective is to avoid arbitrary extrapolation and to build a performance file that is physically meaningful and defensible for academic research.
Any recommendations, example data files, documentation, or previous experience with this issue would be greatly appreciated.
Thank you very much for your help.