Effect of Air Inlet Spacing on Air Distribution and Ventilation Performance of Stratum Ventilation Using Multiple Parallel Jets
An appropriate layout of air terminals can improve the thermal comfort and air quality for room occupants. Stratum ventilation (SV) can efficiently provide thermal comfort and quality of inhaled air. However, investigations into the impact of the supply air inlet spacing on performance under SV are...
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| Format: | Article |
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MDPI AG
2023-03-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/13/7/4143 |
| _version_ | 1797608412233596928 |
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| author | Yaohong Jiang Jiangze Ma Yong Cheng |
| author_facet | Yaohong Jiang Jiangze Ma Yong Cheng |
| author_sort | Yaohong Jiang |
| collection | DOAJ |
| description | An appropriate layout of air terminals can improve the thermal comfort and air quality for room occupants. Stratum ventilation (SV) can efficiently provide thermal comfort and quality of inhaled air. However, investigations into the impact of the supply air inlet spacing on performance under SV are lacking. This study conducted experimental measurements and numerical simulations to analyze the effect of the supply inlet spacing on the air distribution and ventilation performance of the SV. Six theoretical axial velocity attenuation formulas were verified using experimental results. The effective draft temperature for SV (EDTS), air diffusion performance index (ADPI), the local mean age of air (LMAA), and energy utilization coefficient (EUC) were used as the evaluation indexes. The results indicated that the modified Abramovich formula was the most suitable for predicting the attenuation of the axial velocity of multiple parallel jets under SV. At an air supply spacing of 650 mm, the position near the central air supply inlet experienced a cold thermal environment with high air velocity and low air temperature; the positions on both sides of the room were warmer owing to insufficient airflow. The air distribution at these positions improved with increasing air inlet spacing, but some areas could not be covered by the supply airflow. The optimal value of ADPI corresponded to an air inlet spacing of 800 mm, whereas optimal LMAA and EUC corresponded to a spacing of 950 mm. Analysis of a multi-objective optimization method indicated that an air inlet spacing of 800 mm provided optimal overall performance. |
| first_indexed | 2024-03-11T05:43:06Z |
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| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-11T05:43:06Z |
| publishDate | 2023-03-01 |
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| series | Applied Sciences |
| spelling | doaj.art-9ea71d78738845ab8d5d539cd81dfcf12023-11-17T16:16:07ZengMDPI AGApplied Sciences2076-34172023-03-01137414310.3390/app13074143Effect of Air Inlet Spacing on Air Distribution and Ventilation Performance of Stratum Ventilation Using Multiple Parallel JetsYaohong Jiang0Jiangze Ma1Yong Cheng2School of Civil Engineering, Chongqing University, Chongqing 400045, ChinaSchool of Civil Engineering, Chongqing University, Chongqing 400045, ChinaSchool of Civil Engineering, Chongqing University, Chongqing 400045, ChinaAn appropriate layout of air terminals can improve the thermal comfort and air quality for room occupants. Stratum ventilation (SV) can efficiently provide thermal comfort and quality of inhaled air. However, investigations into the impact of the supply air inlet spacing on performance under SV are lacking. This study conducted experimental measurements and numerical simulations to analyze the effect of the supply inlet spacing on the air distribution and ventilation performance of the SV. Six theoretical axial velocity attenuation formulas were verified using experimental results. The effective draft temperature for SV (EDTS), air diffusion performance index (ADPI), the local mean age of air (LMAA), and energy utilization coefficient (EUC) were used as the evaluation indexes. The results indicated that the modified Abramovich formula was the most suitable for predicting the attenuation of the axial velocity of multiple parallel jets under SV. At an air supply spacing of 650 mm, the position near the central air supply inlet experienced a cold thermal environment with high air velocity and low air temperature; the positions on both sides of the room were warmer owing to insufficient airflow. The air distribution at these positions improved with increasing air inlet spacing, but some areas could not be covered by the supply airflow. The optimal value of ADPI corresponded to an air inlet spacing of 800 mm, whereas optimal LMAA and EUC corresponded to a spacing of 950 mm. Analysis of a multi-objective optimization method indicated that an air inlet spacing of 800 mm provided optimal overall performance.https://www.mdpi.com/2076-3417/13/7/4143stratum ventilationair inlet spacingairflowthermal comfortenergy efficiency |
| spellingShingle | Yaohong Jiang Jiangze Ma Yong Cheng Effect of Air Inlet Spacing on Air Distribution and Ventilation Performance of Stratum Ventilation Using Multiple Parallel Jets Applied Sciences stratum ventilation air inlet spacing airflow thermal comfort energy efficiency |
| title | Effect of Air Inlet Spacing on Air Distribution and Ventilation Performance of Stratum Ventilation Using Multiple Parallel Jets |
| title_full | Effect of Air Inlet Spacing on Air Distribution and Ventilation Performance of Stratum Ventilation Using Multiple Parallel Jets |
| title_fullStr | Effect of Air Inlet Spacing on Air Distribution and Ventilation Performance of Stratum Ventilation Using Multiple Parallel Jets |
| title_full_unstemmed | Effect of Air Inlet Spacing on Air Distribution and Ventilation Performance of Stratum Ventilation Using Multiple Parallel Jets |
| title_short | Effect of Air Inlet Spacing on Air Distribution and Ventilation Performance of Stratum Ventilation Using Multiple Parallel Jets |
| title_sort | effect of air inlet spacing on air distribution and ventilation performance of stratum ventilation using multiple parallel jets |
| topic | stratum ventilation air inlet spacing airflow thermal comfort energy efficiency |
| url | https://www.mdpi.com/2076-3417/13/7/4143 |
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