Vacuum insulation enabled energy efficient domestic cooking ovens – A validated numerical study

Abstract

There are approximately 109 million domestic cooking ovens in the UK and USA combined. As maximum energy consumption limits for ovens get stricter, manufacturers are looking for technological solutions to meet regulatory demands. Advanced vacuum insulation technology is increasingly expected to play a significant role in addressing the challenge of delivering energy-efficient equipment. In the current study, we built and validated a full-scale COMSOL Multiphysics-based model of a typical electric domestic cooking oven to assess the effectiveness of a selection of insulation materials including perlite based Vacuum Insulation Panels (VIP/VIPs), silica board and mineral wool. Three turbulent flow models k-ε, k-ω and SST were used to solve for airflow inside the oven cooking cavity. The oven cavity temperature was maintained at 250 °C. The cooking energy consumed was predicted for a range of insulation scenarios with the expanded perlite VIP insulated oven performing best with the lowest energy consumption of 685 Wh and the mineral wool insulated oven the worst with 1384 Wh. Additionally, VIP insulation resulted into a more uniform temperature distribution with a maximum spatial variation of 16.9 K inside the cavity. It is predicted that VIP insulated ovens can save 15.4 MtCO2eq/year in the USA and the UK.