Analysis of Heat Transfer Inside Flexible Thin-Film Channels With Nonuniform Height Distributions

Heat transfer inside flexible thin-film channels having nonuniform height distributions is analyzed in this work. The terminology “flexible thin film channel” is referred to a thin-film channel having two plates separated by soft elastic seals. The fluidic volume enclosed between the plates can expand due to any increase in the fluid pressure. This expansion which is determined from the height (distance between the plates) distribution is related to the pressure drop and the seals stiffness by applications of force or moment balance laws on the mobile plate. The seals stiffness parameter $(S)$⁠, Peclet number (Pe), dimensionless inlet height $(Hi)$⁠, and the aspect ratio $(ε)$ are found to be the controlling parameters. It is found that flexible thin-film channels with flexible plates produce additional cooling over the cooling effect for those having inflexible plates. The heated plate temperature when plates are flexible is lower than that for the other case by more than 14.8% when $Peε<1.0$ and $Hi=3.0$ Moreover, the cooling effect of flexible thin-film channels is found to increase relative to rigid thin-film channels as the $S$ and $Peε$ decrease. Finally, it is recommended to treat flexible thin-film channels as rigid ones when $SA>3.45$ (inflexible plates case) or $SB>10$ (flexible plates case).