Analysis of a thin plate thermo-elastic behaviour with non-Fourier heat transfer: A numerical approach

This study investigates the time-dependent response of a thin plate subjected to thermal waves and variable-time pressure loads. Specifically, we analyze how the thermal wave time lag influences the plate's elastic response when combined with variable pressure loading. A finite difference approach is employed to determine the elastic behavior of the plate under these conditions, utilizing a three-dimensional (spatial and temporal) implicit technique to compute deformation. Our findings reveal that as the duration of the variable pressure load approaches the material's phase lag, the influence of the thermal load becomes more pronounced, leading to fluctuations in plate deflection (ranging from -0.00038 to -0.00023) and resulting in multiple local maxima at 0.376 and 0.8 non-dimensional time units—one associated with the thermal load and the other with the mechanical load. Additionally, changing the plate material from a highly thermally conductive material such as Aluminum (o=1.459x10-12) to a material with a lower thermal wave speed and higher phase lag (o=0.1) results in a 0.024-time shift for the maximum deformation due to thermal expansion and approximately 0.656-time shift for the combined thermal and pressure loading. Furthermore, we found that the time lags between the plate's minimum and maximum deformation and between the applied loads and the response exhibit different trends depending on variations in mechanical load duration (td) and material phase lag (o). Synchronizing the thermal wave with the applied pressure minimizes the time lag, whereas staggering them may result in a time lag of up to 1.9 non-dimensional time units.