Jaeger, MarvinMarvinJaegerBecker, MaximilianMaximilianBeckerOrth, MaikeMaikeOrthSchulz, SimonSimonSchulzHeinrich, StefanStefanHeinrichKern, Thorsten A.Thorsten A.KernKoelpin, AlexanderAlexanderKoelpin2026-10-262026-10-262026-10-16Industrial & Engineering Chemistry Research (in Press): (2026)https://hdl.handle.net/11420/65463Real-time monitoring within industrial processing vessels is essential for advancing process analytical technology. Flow-following sensors represent an ideal approach for delivering continuous, in-line data from the process stream. However, deploying these mobile sensors is constrained by the physical barriers of sealed metallic vessels and harsh, battery-hostile environments. To overcome these limitations, a non-invasive, retrofittable wireless power transfer system is presented. The metallic vessel is structurally repurposed into a 5.23 GHz multi-mode microwave cavity resonator by coupling microwave energy through existing standard flanges. Electromagnetic simulations validate that this method generates continuous energy coverage throughout dynamic flow zones, demonstrated using a fluidized bed granulator as an application example. To harness this energy, an omnidirectional antenna and a compact RF-to-DC rectifier prototype were developed. By enabling the continuous operation of autonomous, battery-free mobile sensor nodes, this framework provides a practical, scalable foundation for high-density spatial analytics and data-driven industrial optimization.en1520-50452026American Chemical Society (ACS)https://creativecommons.org/licenses/by/4.0/Technology::660: Chemistry; Chemical Engineering::660.2: Chemical EngineeringTechnology::621: Applied Physics::621.3: Electrical Engineering, Electronic EngineeringJournal Article10.1021/acs.iecr.6c0115710.15480/882.1903010.15480/882.16850