Improvement of a Diagnostic Urban Wind Model for Flow Fields around a Single Rectangular Obstacle in Micrometeorology Simulation
In general, computational fluid dynamics (CFD) models incur high computational costs when dealing with realistic and complicated flows. In contrast, the mass-consistent flow (MASCON) field model provides a three-dimensional flow field at reasonable computational cost. Unfortunately, some weaknesses...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-07-01
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| Series: | Fluids |
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| Online Access: | https://www.mdpi.com/2311-5521/6/7/254 |
| _version_ | 1827687592526610432 |
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| author | Mitsufumi Asami Arata Kimura Hideyuki Oka |
| author_facet | Mitsufumi Asami Arata Kimura Hideyuki Oka |
| author_sort | Mitsufumi Asami |
| collection | DOAJ |
| description | In general, computational fluid dynamics (CFD) models incur high computational costs when dealing with realistic and complicated flows. In contrast, the mass-consistent flow (MASCON) field model provides a three-dimensional flow field at reasonable computational cost. Unfortunately, some weaknesses in simulating the flow of the wake zone exist because the momentum equations are not considered in the MASCON field model. In the present study, a new set of improved algebraic models to provide initial flow fields for the MASCON field model are proposed to overcome these weaknesses by considering the effect of momentum diffusion in the wake zone. Specifically, these models for the wake region are developed on the basis of the wake models used in well-recognized Gaussian plume models, ADMS-build and PRIME. The MASCON fields provided by the new set of wake zone models are evaluated against wind-tunnel experimental data on flow around a wall-mounted rectangular obstacle. Each MASCON field is compared with the experimental results, focusing on the positions of the vortex core and saddle points of the vortex formed in the near-wake zone and the vertical velocity distribution in the far-wake zone. The set of wake zone models developed in the present study better reproduce the experimental results in both the wake zones compared to the previously proposed models. In particular, the complicated recirculation flow which is formed by the union of the sidewall recirculation zone and the near-wake zone is reproduced by the present wake zone model using the PRIME model that includes the parameterization of the sidewall recirculation zones. |
| first_indexed | 2024-03-10T09:39:23Z |
| format | Article |
| id | doaj.art-8ffcc25b90a74396a02629d6e4e56e70 |
| institution | Directory Open Access Journal |
| issn | 2311-5521 |
| language | English |
| last_indexed | 2024-03-10T09:39:23Z |
| publishDate | 2021-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Fluids |
| spelling | doaj.art-8ffcc25b90a74396a02629d6e4e56e702023-11-22T03:46:20ZengMDPI AGFluids2311-55212021-07-016725410.3390/fluids6070254Improvement of a Diagnostic Urban Wind Model for Flow Fields around a Single Rectangular Obstacle in Micrometeorology SimulationMitsufumi Asami0Arata Kimura1Hideyuki Oka2Marine Environment and Engine System Department, National Maritime Research Institute, National Institute of Maritime, Port and Aviation Technology, Shinkawa 6-38-1, Mitaka-shi, Tokyo 181-0004, JapanMaritime Risk Assessment Department, National Maritime Research Institute, National Institute of Maritime, Port and Aviation Technology, Shinkawa 6-38-1, Mitaka-shi, Tokyo 181-0004, JapanMaritime Risk Assessment Department, National Maritime Research Institute, National Institute of Maritime, Port and Aviation Technology, Shinkawa 6-38-1, Mitaka-shi, Tokyo 181-0004, JapanIn general, computational fluid dynamics (CFD) models incur high computational costs when dealing with realistic and complicated flows. In contrast, the mass-consistent flow (MASCON) field model provides a three-dimensional flow field at reasonable computational cost. Unfortunately, some weaknesses in simulating the flow of the wake zone exist because the momentum equations are not considered in the MASCON field model. In the present study, a new set of improved algebraic models to provide initial flow fields for the MASCON field model are proposed to overcome these weaknesses by considering the effect of momentum diffusion in the wake zone. Specifically, these models for the wake region are developed on the basis of the wake models used in well-recognized Gaussian plume models, ADMS-build and PRIME. The MASCON fields provided by the new set of wake zone models are evaluated against wind-tunnel experimental data on flow around a wall-mounted rectangular obstacle. Each MASCON field is compared with the experimental results, focusing on the positions of the vortex core and saddle points of the vortex formed in the near-wake zone and the vertical velocity distribution in the far-wake zone. The set of wake zone models developed in the present study better reproduce the experimental results in both the wake zones compared to the previously proposed models. In particular, the complicated recirculation flow which is formed by the union of the sidewall recirculation zone and the near-wake zone is reproduced by the present wake zone model using the PRIME model that includes the parameterization of the sidewall recirculation zones.https://www.mdpi.com/2311-5521/6/7/254mass-consistent flow (MASCON) modeldiagnostic wind field modelalgebraic models for flow fields |
| spellingShingle | Mitsufumi Asami Arata Kimura Hideyuki Oka Improvement of a Diagnostic Urban Wind Model for Flow Fields around a Single Rectangular Obstacle in Micrometeorology Simulation Fluids mass-consistent flow (MASCON) model diagnostic wind field model algebraic models for flow fields |
| title | Improvement of a Diagnostic Urban Wind Model for Flow Fields around a Single Rectangular Obstacle in Micrometeorology Simulation |
| title_full | Improvement of a Diagnostic Urban Wind Model for Flow Fields around a Single Rectangular Obstacle in Micrometeorology Simulation |
| title_fullStr | Improvement of a Diagnostic Urban Wind Model for Flow Fields around a Single Rectangular Obstacle in Micrometeorology Simulation |
| title_full_unstemmed | Improvement of a Diagnostic Urban Wind Model for Flow Fields around a Single Rectangular Obstacle in Micrometeorology Simulation |
| title_short | Improvement of a Diagnostic Urban Wind Model for Flow Fields around a Single Rectangular Obstacle in Micrometeorology Simulation |
| title_sort | improvement of a diagnostic urban wind model for flow fields around a single rectangular obstacle in micrometeorology simulation |
| topic | mass-consistent flow (MASCON) model diagnostic wind field model algebraic models for flow fields |
| url | https://www.mdpi.com/2311-5521/6/7/254 |
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