Impact of Outlet Vent Configurations on Indoor Environmental Quality, Occupant Comfort, and Energy Efficiency: An Optimisation Study

Abstract

The rising demand for building energy and the time spent indoors are driving the need for a sustainable balance between building energy demand and occupant comfort. The detailed analysis of fluid flow, radiation heat transfer, heat load on a radiator, and the comfort of indoor occupants is essential for sustainable buildings. This study numerically evaluates the well-validated 3D empty-room model for energy demand in a cold-climate environment to support occupant comfort. Efforts have been made to optimise the factors affecting occupant comfort and the energy demand of the office room to maintain sustainable stability. A well-validated 3-dimensional model simulated airflow, heat transfer, and occupant comfort. The study optimises factors affecting comfort and energy use using multi-objective optimisation (MOO) techniques. Outlet vent location significantly impacts indoor comfort, energy, and fluid flow. Indoor environments can be optimised for both energy and comfort, especially in symmetrical indoor spaces. Floor-level vents improve air circulation but have little impact on energy use in cold climates. In symmetrical fluid domains, symmetrical outlet vent placement achieved the lowest objective function value (0.026), with a heat load of 412.27 W, PMV of 0.24, and PPD of 7.12, whereas floor-level outlet vents showed the highest objective function value (0.575), with PMV of 0.51 and PPD of 12.11, indicating reduced comfort. Overall, optimising ventilation strategies allows for prioritising occupant comfort and energy efficiency based on specific needs.