Effects of Attaching Baffles onto the Inclined Walls of Attic Frames for Purposes of Energy Conservation

Abstract

This article addresses the buoyant air circulation inside attic spaces of houses and buildings with sloped roofs and horizontally suspended ceilings. In order to counteract the excessive heat transmission through the roof that takes place during the wintertime, when the attic is heated at the base, this study attached an array of baffles onto the top inclined walls to alter the flow characteristics of the buoyant air. To perform the computational analysis, the finite volume method is the vehicle for the discretization of the conservation equations. The Boussinesq approximation is not invoked, and all thermophysical properties are considered as temperature-dependent. Simulations are performed for several values of baffles length and the Rayleigh number. The influence of these parameters upon the flow and temperature patterns is analyzed and discussed. A comparison of the thermal performance between baffled attics and non-baffled attics is presented. The results show that the presence of baffles provides an important energy savings for heating and helps keep the attic at a desired temperature.