Analyzing the Sensitivity of the LES PALM Model to Building Parameters Using an Archetype-Based Approach

The interaction between urban microclimate and building energy balance is pivotal in comprehending urban thermal behavior, with buildings' energy use contributing to waste heat that affects the intricate mass and momentum transactions characteristic of urban microclimates. Large-Eddy Simulation (LES) models have improved insights into these complex dynamics due to increased computational power. However, complexities and data uncertainties in real urban settings may compromise LES accuracy. Therefore, understanding model sensitivity to input data uncertainties is crucial for assessing potential deviations and prioritizing data collection parameters.

This study scrutinizes the PALM model 6.0's sensitivity to building typologies and parameters within a residential quarter of Bochum, Germany, examining the trade-offs of modeling detail. Four divergent scenarios are considered. The baseline scenario presupposes homogeneity in building types across the model domain. The second scenario applies PALM’s standard building categories, predominantly delineating four types aligned with building age and building use. The third scenario encompasses an array of 28 building typologies, integrating the TABULA archetypes from the IEE Project 'Typology Approach for Building Stock Energy Assessment'. The first three scenarios maintain a consistent level of architectural specificity within the parent and the child domain, configured as a nesting structure. The fourth scenario distinguishes itself by combining PALM's predefined standard building typologies within the parent domain with the 28 distinct TABULA archetypes within the child domain. ​The underlying hypothesis suggests that increasing the detail in building parameters can potentially amplify the realism of urban environment simulations and augment the accuracy of the results. However, such advancements come with heightened computational demands and more extensive data requirements. The study emphasizes the importance of balancing these considerations to ascertain the most advantageous degree of detail, tailored to various simulation pursuits.