Future Work
Further testing is to be carried out, investigating wider ranges of temperatures and operating conditions. New heat exchanger relationships will be derived to better predict the effectiveness values, which will bring the model in to better agreement with the actual results. With the model
refined, full year simulations in TRNSYS will be carried out to determine seasonal solar fraction values for the ISAHP system.
The experimental results matched well with the simulated results for the compressor power input, but the simulation over predicted the performance on the system. The compressor power input ranged from 484 - 635 W, and the COP of the system ranged from 2.4 - 3.2 over the duration of the test. The computer model predicted the dynamic operation of the system well, except for a 12% overestimation of performance due to the model’s effectiveness relationships. New seasonal solar fraction values and life cycle cost numbers will be calculated once the full year simulations are completed in TRNSYS.
Support for this work was provided by the Solar Buildings Research Network of Canada, the Ontario Graduate Scholarship Program, and the Natural Science and Engineering Research Council of Canada.
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