A New Customized Measurement System for a Non-Contact, Enhanced Thermometric Method

This study introduces a novel, low-cost, non-contact measurement system for heat flux estimation based on an enhanced thermometric method. The customized system was designed and assembled to implement a non-contact, indirect approach for heat flux assessment. Developed as an affordable alternative to conventional contact-based techniques, it is suitable for historical buildings, where invasive sensors could compromise structural integrity. The system integrates real-time data acquisition, remote access via a web-based interface, and automated data processing, enhancing both usability and efficiency. Laboratory tests were conducted to evaluate its performance, with results compared against data from widely used heat flow plates and air/surface temperature sensors. The results showed good agreement between the proposed method and the reference data. Small differences were observed between the values measured by the air temperature sensors (0.10 °C on average), as well as by the contact and non-contact surface temperature sensors (0.12 °C on average). Finally, percentage variations between −6% and −5% in terms of heat fluxes confirmed the reliability of the non-contact approach. These findings provide a strong foundation for further testing, including applications in real buildings.