Submission
Performance of integrated R744-packs Part 1 - Compressor mass flow estimation based on data driven models using analytical methods and actual field measurement
DOI: 10.18462/iir.compr.2021.0390
Session: Field measurements
Accept state: Submission accepted
Authors
| Name | Organization | |
|---|---|---|
| Vahid Khorshidi, MSc. | Danfoss A/S | |
| Ekaterini Kriezi, PhD | Danfoss A/S | |
| Christian Schlemminger, Dr.Ing. / PhD | SINTEF Energy Research | |
| Engin Söylemez, PhD | Norwegian University of Science and Technology NTNU | |
| Armin Hafner, Professor | Norwegian University of Science and Technology NTNU |
Abstract
Rising concerns for climate change repercautions along with the new legislations aimed at lowering emissions indicates the inevitable transition in cooling/heating industry towards a more energy efficient solutions with minimal environmental impact. Integrated refrigeration, air condition and heat recovery solutions by CO2(R744) packs are efficient solutions to high energy demanding building (supermarkets and hotels). Proven performance enhancement of Multi Ejector Solution(TM) makes the R744 systems more energy efficient, especially in warm climates, compared to the most conventional synthetic refrigerant systems in food retail application.
Pilot installation in the frame of MultiPack, an EU funded project, provided a wide range of data, offering the possibility of evaluating real performance of each ejector group: high pressure (HP), low pressure (LP) and liquid ejector(LE), by running the system in different operating modes. Analysis on the data indicated performance improvement of a system with ejector, on average a 35% lower energy consumption compared to baseline parallel compression R744 system without ejectors.
Availability of mass flow measurement, 6 Coriolis mass flow meters on this pilot, enabled the possibility of comparison of mass flow rate estimation based on data acquisition from compressors with actual measurement. Methods utilized include: Energy balance, volumetric displacement, manufacturer polynomials and data driven method. The comparison reviles the impotence of compressor suction and discharge parameters to for reliable results based on energy balance, volumetric displacement, manufacturer polynomials. The data driven method preforms well after sufficient training time.
Keywords
R744 (CO2), Ejectors, Integrated systems, Refrigeration, Data-driven models, Energy saving