Summary
In this study, the accuracies of the homogeneous equilibrium (HEM) and homogeneous relaxation models (HRM) were compared. Both models were implemented in the ejectorPL computational tool. The HEM and HRM were used to simulate the carbon dioxide flow in ejectors that were designed for supermarket refrigeration systems. The model accuracy was evaluated by comparing the computational results with the experimental data. The discrepancy between the measured and computed motive nozzle mass flow rates was analysed. In addition, the difference between the experimental and computational mass entrainment ratios was calculated. The operating regimes in this study ranged from 47 bar to 94 bar and from 6 °C to 36 °C for the pressure and temperature, respectively. The model accuracy strongly depends on the distance between the operating regime and the critical point of the refrigerant. The discrepancy for the selected operating regimes ranged from 0.3% to 43.3% and 0.7% to 42.0% for HEM and HRM, respectively. For lower pressures and temperatures, the HRM has higher accuracy than the HEM. The errors of the HRM results were approx. 5% lower than those of the HEM results. The accuracy improvement of the HRM was considered unsatisfactory. The low accuracy improvements were possibly caused by the relaxation time formulation in the homogeneous relaxation model.
Details
- Original title: HEM and HRM accuracy comparison for the simulation of CO2 expansion in two-phase ejectors for supermarket refrigeration systems.
- Record ID : 30021161
- Languages: English
- Source: Applied Thermal Engineering - vol. 115
- Publication date: 2017/03/25
- DOI: http://dx.doi.org/10.1016/j.applthermaleng.2016.12.122
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Critical comparison between single-phase ejecto...
- Author(s) : PAEZ A., HABERSCHILL P., REVELLIN R., MICHEL B., TOBALY P., BALLOT-MIGUET B.
- Date : 2022/06/13
- Languages : English
- Source: 15th IIR-Gustav Lorentzen Conference on Natural Refrigerants (GL2022). Proceedings. Trondheim, Norway, June 13-15th 2022.
- Formats : PDF
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Application range of the HEM approach for CO2 e...
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- Date : 2015/11
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- Source: International Journal of Refrigeration - Revue Internationale du Froid - vol. 59
- Formats : PDF
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Theoretical model of transcritical CO2 ejector ...
- Author(s) : ZHU Y., JIANG P.
- Date : 2018/02
- Languages : English
- Source: International Journal of Refrigeration - Revue Internationale du Froid - vol. 86
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CFD simulations of a two-phase ejector for tran...
- Author(s) : COLOMBO A., CONTI P., ORLANDI M., et al.
- Date : 2018/06/18
- Languages : English
- Source: 13th IIR Gustav Lorentzen Conference on Natural Refrigerants (GL2018). Proceedings. Valencia, Spain, June 18-20th 2018.
- Formats : PDF
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Performance analysis of a modified dual-ejector...
- Author(s) : LIU J., YU J.
- Date : 2021/11
- Languages : English
- Source: International Journal of Refrigeration - Revue Internationale du Froid - vol. 131
- Formats : PDF
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