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The current investigation, determines the effects of rib shape and its parameters on an inner flow in which a circular cylinder exist in the middle. The problem is solved in 2 dimensional methods and the distance from the channel's entrance to cylinder is 125 mm. Ansys 14.5 is used for modeling the geometry and meshing of the problem and for modeling the turbulence the k − ε (realizable) is employed. In this study rib and its four parameters of pitch (p), length (h), rib's height (e) and the distance from the cylinders' head to start of rib (a) in a cavitation flow is investigated. The results show that none of rib's parameters has a direct relation with void fraction. The values for these parameters are different for the maximum or the minimum cavitation; namely if a rib's pitch increases and surpasses a specific value, it will reduce the effect of the previous rib in the flow. In fact, the turbulence eradicates before it become more turbulent by the next rib. On the other hand, if the rib's pitch is too small the flow traps between the two ribs and stagnation happens which is the key element in plummeting the pressure and forming cavity. For other parameters either no correlation with void fraction is observed.

Thermal wave and dual phase lag bioheat transfer equations are solved analytically in the skin tissue exposed to oscillatory and constant surface heat flux. Comparison between the application of Fourier and non-Fourier boundary conditions on the skin tissue temperature distributions is studied. The amplitude of temperature responses increases and also the phase shift between the temperature responses and heat flux decreases under the non-Fourier boundary conditions for the case of an oscillatory surface heat flux. It is supposed the stable temperature cycles in order to estimate the blood perfusion rate via the existing phase shift between the surface heat fluxes and the temperature responses. It is shown that the higher rates of the blood perfusion correspond to lower phase shift between the surface temperature responses and the imposed heat flux. C⃝ 2015 Wiley Periodicals, Inc. Heat Trans Asian Res, 46(1): 29-48, 2017; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj).