Sculpting the "Aesthetics of Air" for Improved Thermal Comfort

Abstract

In an attempt to reduce building energy consumption and carbon emissions there is a growing worldwide interest in utilizing natural ventilation cooling in future high rise buildings. The use of natural ventilation cooling is not new to hot and humid regions of the world, yet this passive design principle found in tropical vernacular architecture is not found in many tall buildings in the tropics. The economically preferred double loaded corridor (DLC) spatial configuration generally associated with high rise models lack the ability to cross ventilate efficiently thereby surrendering to mechanical cooling for thermal comfort. The fundamental challenge is finding a solution that works well with cross ventilation and DLC configuration to improve thermal comfort and reduce building energy consumption. The skip-stop spatial configuration found in Le Corbusier’s Unité d’Habitation could be a solution in providing efficient cross ventilation for double loaded corridor designs and thus improve thermal comfort through passive cooling while providing efficient space planning for vertical development. The objective of this project was to investigate the ventilation performances and thermal comfort conditions of a proposed skip-stop double loaded corridor (SSDLC) spatial configuration in comparison to a DLC and single loaded corridor (SLC) configuration. Modifications to the building envelope and local air speeds via ceiling fans through parametric analyses were also tested to improve comfort in these naturally ventilated models. Estimated thermal comfort results in these models were not seen as absolute but relative to the conditions being investigated. The research evaluates each model in Honolulu’s climate. Thermal comfort and air flow analysis was conducted using bulk air flow and computational fluid dynamic (CFD) modeling through the Integrated Environmental Solutions (IES) Virtual Environment software. The Predicted Mean Vote (PMV) model was used as a metric to determine acceptable thermal comfort. The resulting research is beneficial for architects practicing in Hawaii and other major tropical cities around the world, as it provides a passive and economic solution to the cross ventilation and double loaded corridor dilemma in tall building designs, not to mention the energy savings that could potentially come out of utilizing such model in a hot and humid climate.