Model-based optimizations of packaged rooftop air conditioners using low global warming potential refrigerants

Shen, Bo; Abdelaziz, Omar; Shrestha, Som; Elatar, Ahmed

doi:10.1016/j.ijrefrig.2017.10.028

Title: Model-based optimizations of packaged rooftop air conditioners using low global warming potential refrigerants

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Abstract

Based on laboratory investigations for R-22 and R-410A alternative low GWP refrigerants in two baseline rooftop air conditioners (RTU), the DOE/ORNL Heat Pump Design Model was used to model the two RTUs and the models were calibrated against the experimental data. We compared the compressor efficiencies and heat exchanger performances. An efficiency-based compressor mapping method was developed. Extensive model-based optimizations were conducted to provide a fair comparison between all the low GWP candidates by selecting optimal configurations. The results illustrate that all the R-22 low GWP refrigerants will lead to slightly lower COPs. ARM-20B appears to be the best R-22 replacement at normal conditions. At higher ambient temperatures, ARM-20A exhibits better performance. All R-410A low GWP candidates will result in similar or better efficiencies than R-410A. R-32 has the best COP while requiring the smallest compressor. Finally, R-452B uses the closest compressor displacement volume and achieves the same efficiency as R-410A.

Authors:

Shen, Bo ^[1]; Abdelaziz, Omar ^[1]; Shrestha, Som ^[1]; Elatar, Ahmed ^[1]

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Building Technologies Research and Integration Center

Publication Date:: Tue Oct 31 00:00:00 EDT 2017

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Energy Efficiency Office. Building Technologies Office

OSTI Identifier:: 1423085

Alternate Identifier(s):: OSTI ID: 1582937

Grant/Contract Number:: AC05-00OR22725

Resource Type:: Accepted Manuscript

Journal Name:: International Journal of Refrigeration

Additional Journal Information:: Journal Volume: 87; Journal ID: ISSN 0140-7007

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 42 ENGINEERING; 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; Global warming potential; Rooftop air conditioner; Modeling; Optimization; Alternative refrigerants

Citation Formats


                    Shen, Bo, Abdelaziz, Omar, Shrestha, Som, and Elatar, Ahmed. Model-based optimizations of packaged rooftop air conditioners using low global warming potential refrigerants.  United States: N. p., 2017. 
Web.  doi:10.1016/j.ijrefrig.2017.10.028.

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                    Shen, Bo, Abdelaziz, Omar, Shrestha, Som, & Elatar, Ahmed. Model-based optimizations of packaged rooftop air conditioners using low global warming potential refrigerants.  United States.  https://doi.org/10.1016/j.ijrefrig.2017.10.028

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                    Shen, Bo, Abdelaziz, Omar, Shrestha, Som, and Elatar, Ahmed. Tue .  
"Model-based optimizations of packaged rooftop air conditioners using low global warming potential refrigerants".  United States.  https://doi.org/10.1016/j.ijrefrig.2017.10.028.  https://www.osti.gov/servlets/purl/1423085.

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@article{osti_1423085,

  title        = {Model-based optimizations of packaged rooftop air conditioners using low global warming potential refrigerants},

  author       = {Shen, Bo and Abdelaziz, Omar and Shrestha, Som and Elatar, Ahmed},

  abstractNote = {Based on laboratory investigations for R-22 and R-410A alternative low GWP refrigerants in two baseline rooftop air conditioners (RTU), the DOE/ORNL Heat Pump Design Model was used to model the two RTUs and the models were calibrated against the experimental data. We compared the compressor efficiencies and heat exchanger performances. An efficiency-based compressor mapping method was developed. Extensive model-based optimizations were conducted to provide a fair comparison between all the low GWP candidates by selecting optimal configurations. The results illustrate that all the R-22 low GWP refrigerants will lead to slightly lower COPs. ARM-20B appears to be the best R-22 replacement at normal conditions. At higher ambient temperatures, ARM-20A exhibits better performance. All R-410A low GWP candidates will result in similar or better efficiencies than R-410A. R-32 has the best COP while requiring the smallest compressor. Finally, R-452B uses the closest compressor displacement volume and achieves the same efficiency as R-410A.},

  doi          = {10.1016/j.ijrefrig.2017.10.028},

  journal      = {International Journal of Refrigeration},

  number       = ,

  volume       = 87,

  place        = {United States},

  year         = {Tue Oct 31 00:00:00 EDT 2017},

  month        = {Tue Oct 31 00:00:00 EDT 2017}

}

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