Luleå University of Technology

Flow of power-law fluids in thin straight tubes of non-uniform cross-section

Abstract We analyze the asymptotic behavior of solutions to a boundary value problem describing the flow of a non-Newtonian so-called power-law fluid in a thin tube with a variable cross-section depending on a small parameter $$\varepsilon$$ , representing the ratio between the c...

Time-Varying Electromagnetic Systems - Challenges and Methodologies

Time-varying (TV) electromagnetic (EM) systems and devices introduce a fundamentally new framework in EM theory by extending classical concepts beyond traditional time-invariant formulations. In conventional EM systems, temporal invariance combined with the steady-state assumptio...

Effect of Drying at 120 °C and 150 °C on Selected Mechanical Properties of Silver Fir (Abies alba Mill.)

High-temperature drying can considerably improve drying efficiency. However, information on its impact on the mechanical properties of silver fir during industrial high-temperature drying remains limited. Elevated drying temperatures may induce changes in wood structure that can...

Fire behaviour of thermo-mechanically densified wood

Abstract This study investigates the effect of thermo-mechanical densification on the fire behaviour of wood using cone calorimetry. Scots pine wood was thermo-mechanically densified from an initial thickness of 20 mm to target thicknesses of 14 and 10 mm and compared with non-de...

Interpretable modeling for material transportation process in an industrial cement vertical roller mill

Abstract Vertical roller mills (VRMs) dominate cement finish grinding because of their high efficiency and dry operation. However, the interaction among ventilation, fan operation, and pneumatic material transport remains poorly quantified using plant data. In this study, the pre...

Surface microbial dynamics and residual diversity in patient rooms with wooden and painted walls

Wood is a biobased material that supports long-term carbon storage; however, its suitability for use in healthcare facility interiors remains insufficiently studied. This study assessed surface microbial dynamics and residual diversity in patient rooms with conventional painted w...