Full implementation of non-orthogonal surfaces within the PALM model

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985807%3A_____%2F25%3A00638182" target="_blank" >RIV/67985807:_____/25:00638182 - isvavai.cz</a>

Výsledek na webu

<a href="https://meetingorganizer.copernicus.org/ICUC12/ICUC12-723.html" target="_blank" >https://meetingorganizer.copernicus.org/ICUC12/ICUC12-723.html</a>

DOI - Digital Object Identifier

—

Jazyk výsledku

angličtina

Název v původním jazyce

Full implementation of non-orthogonal surfaces within the PALM model

Popis výsledku v původním jazyce

ZÁKLADNÍ ÚDAJE: ICUC12 Abstracts. Rotterdam: ICUC, 2025, č. článku 723.. [ICUC 2025: International Conference on Urban Climate /12./. 07.07.2025-11.07.2025, Rotterdam & online]. ABSTRAKT: The orthogonal 3D grid used in PALM and other atmospheric models brings challenges in representing resolved obstacles (such as terrain or buildings) with non-orthogonal surfaces. The simple binary form of representation, in which each grid cell is either entirely atmospheric or obstacle, causes aliasing effects (artificial stairs). It has been demonstrated that this leads to significant biases in radiation, surface energy balance and fluid dynamics. The newly introduced PALM slanted surface option involves new methods in the Radiative Transfer Model (RTM) and the surface-related modules in PALM, and it enables a more faithful representation of non-orthogonal surfaces while preserving the PALM’s Arakawa-C model grid without inducing significant performance penalty. For surface-atmospheric interactions, the cut-cell approach is used. In the RTM, a new representation of surface elements is introduced for both raytracing in the preprocessing phase and radiosity-based interactions in the time-stepping phase of the simulation. The format of the input data had to be extended to accommodate the representation of the slanted surfaces. The open-source input processor PALM-GeM is able to prepare slanted surface PALM inputs using various geographic data. Validation and benchmarking results from synthetic and real-case scenarios are presented. The slanted surface model is also being prepared for wind tunnel validation.

Název v anglickém jazyce

Full implementation of non-orthogonal surfaces within the PALM model

Popis výsledku anglicky

ZÁKLADNÍ ÚDAJE: ICUC12 Abstracts. Rotterdam: ICUC, 2025, č. článku 723.. [ICUC 2025: International Conference on Urban Climate /12./. 07.07.2025-11.07.2025, Rotterdam & online]. ABSTRAKT: The orthogonal 3D grid used in PALM and other atmospheric models brings challenges in representing resolved obstacles (such as terrain or buildings) with non-orthogonal surfaces. The simple binary form of representation, in which each grid cell is either entirely atmospheric or obstacle, causes aliasing effects (artificial stairs). It has been demonstrated that this leads to significant biases in radiation, surface energy balance and fluid dynamics. The newly introduced PALM slanted surface option involves new methods in the Radiative Transfer Model (RTM) and the surface-related modules in PALM, and it enables a more faithful representation of non-orthogonal surfaces while preserving the PALM’s Arakawa-C model grid without inducing significant performance penalty. For surface-atmospheric interactions, the cut-cell approach is used. In the RTM, a new representation of surface elements is introduced for both raytracing in the preprocessing phase and radiosity-based interactions in the time-stepping phase of the simulation. The format of the input data had to be extended to accommodate the representation of the slanted surfaces. The open-source input processor PALM-GeM is able to prepare slanted surface PALM inputs using various geographic data. Validation and benchmarking results from synthetic and real-case scenarios are presented. The slanted surface model is also being prepared for wind tunnel validation.

Druh

O - Ostatní výsledky

CEP obor

—

OECD FORD obor

10509 - Meteorology and atmospheric sciences

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů