Publications Repository - Gdańsk University of Technology

Since the COVID-19 pandemic, protection against pathogenic germs and surface disinfection have become critical issues. Most effective bacteria/virus inactivation methods are either power-consuming or require using caustic chemical substances. Herein, thermal inactivation appears to be an affordable and effective technique as long as high temperatures are reached quickly and long-termly maintained. Therefore, the preparation of a chamber that accomplishes this purpose has been envisioned, designed and manufactured, allowing significant germ inactivation and offering an effective tool for water purification stations. In this regard, this work proposes applying 16-16-65-nm laser-illuminated gold nanorods (AuNRs) as a non-standard heat source, which can produce the generated heat inside a considered volume. Consequently, the locations of AuNRs deposited on glass platforms, stuck on the internal or external chamber’s walls, from two sides, were investigated to intensify the heat transfer processes upon the entire chamber. To verify the efficiency of the energy conversion from light to heat, spectroscopy techniques and laser power meters were used. Similarly, temperature fields at the illuminated platforms were solved using the Computational Fluid Dynamics (CFD) equations and two different theoretical models which adopt the Rayleigh approximation and consider the delivered heat flux with a fixed efficiency, respectively. The considered Models were verified using a calibrated and highly-resolved thermal camera. Upon 900-mW 808-nm laser illumination for 50 min, the temperature of the platforms increased by οܶ ൎ ͷ͹ǤͳԨ and οܶ ൎ ͵ͺͺǤ͵Ԩ for an unfocused and focused beam, respectively. However, the quickest heat diffusion process is visible when the AuNR platform is situated in the internal position of the chamber, offering οܶ ൎ ͵ͻǤͶԨ after 50 min of illumination.

Authors

• mgr inż. Piotr Radomski link open in new tab ,
• dr inż. Dominik Kreft link open in new tab ,
• Maria Nevarez Martinez link open in new tab ,
• dr Aimad Koulali link open in new tab ,
• Iuliia Mukha,
• profesor Luciano De Sio,
• dr inż. Paweł Ziółkowski link open in new tab ,
• prof. dr hab. inż. Dariusz Mikielewicz link open in new tab