Abstract
We present complementary numerical and asymptotic studies of the flow over a heated, semi-infinite flat plate for a fluid with temperature-dependent viscosity. Liquid-type viscosities are found to entrain both the velocity and temperature profiles closer to the plate with increasing temperature sensitivity; gas-type viscosities are found to exhibit the reverse effect. A linear stability analysis is presented and we find that increasing the temperature dependence of the fluid (from gas- to liquid-type behavior) results in an increased critical Reynolds number to a point of maximum stability. Using an energy-balance approach, we determine that this behavior is primarily driven by the inviscid instability of the modified steady flow, rather than being a result of modified viscous instability effects. Application and extension of the results are considered in the context of chemical vapor deposition.
Highlights
The Blasius boundary layer has been a staple of fluid mechanics since its inception in the early 20th century [1]
The study we present here can be considered as the first step in analyzing the stability of two-dimensional temperature-dependent viscosity flows related to the process of chemical vapor deposition; the nonparallel, nonlinear, and non-normal approaches utilized in the aforementioned studies are clearly possible extensions of our work
V we discuss the physical interpretation of these results, as well as briefly considering their impact when applied to chemical vapor deposition (CVD) and the expansion of this work into a detailed model of flow stability in a horizontal CVD reactor
Summary
The Blasius boundary layer has been a staple of fluid mechanics since its inception in the early 20th century [1]. The inverse linear temperature dependence of viscosity is considered by Jasmine and Gajjar [18] in their study of flow stability over a rotating disk There they observe the same effects as Kafoussias and Williams [16] for the disk boundary layer, as well as finding that a viscosity that decreases more rapidly with increasing temperature destabilizes the flow. Modifications to the stability solutions of Blasius-type flows have shown that destabilizing effects are possible, as demonstrated by Wall and Wilson [17], where a critical Reynolds number of approximately 220 is achieved at one extreme of their viscosity temperature-dependence parameter. V we discuss the physical interpretation of these results, as well as briefly considering their impact when applied to CVD and the expansion of this work into a detailed model of flow stability in a horizontal CVD reactor
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
