Optimising thermal efficiency in high-temperature tube furnaces: An investigation on thermal insulations

• Insulation in tube furnaces is optimised via simulations and experiments. • A novel gradient-based method quantifies insulation effectiveness. • Al 2 O 3 and SiC are assessed under dynamic conditions. • Gas flow and target temperature impact thermal efficiency. Effective thermal management is crucial for the efficiency of high-temperature reactors, particularly those designed for industrial decarbonisation. However, optimising thermal insulation in these reactors remains a challenge due to limited methods for accurately assessing insulation performance under operational conditions. Current approaches lack the precision needed to guide material selection for minimising energy losses, leaving a critical gap in reactor design and energy efficiency. Advanced simulations were combined with experimental validation to evaluate and optimise thermal insulation materials within a specialised high-temperature reactor. A novel quantitative method based on temperature gradient analysis within the reactor was introduced, providing a robust framework for assessing insulation effectiveness. Additionally, a comprehensive simulation-based case study quantifies energy losses, validating the practical benefits of the optimised materials. These findings connect the existing gap in thermal insulation evaluation, offering key insights into enhancing energy efficiency. This work not only advances reactor design but also lays the groundwork for improved thermal management strategies across a wide range of high-temperature industrial applications.