On the Dynamic Shear Flow Problem for Viscoelastic Liquids

1987 ◽  
Vol 18 (4) ◽  
pp. 972-990 ◽  
Author(s):  
Hans Engler
Keyword(s):  
Shear Flow ◽  
Flow Problem ◽  
Dynamic Shear ◽  
Viscoelastic Liquids

The Relationship between Feed Rate and Point Angle of a Twist Drill Bit When Drilling Bone

1980 ◽  
Vol 9 (3) ◽  
pp. 137-142
Author(s):  
J K Davis ◽  
C J Jackson ◽  
I Scott
Keyword(s):  
Shear Flow ◽  
Feed Rate ◽  
Thermal Effects ◽  
Orthogonal Cutting ◽  
Human Bone ◽  
Bovine Bone ◽  
Drill Bit ◽  
Twist Drill ◽  
Dynamic Shear ◽  
The Relationship

The work described in this paper was carried out in two parts. The first part consisted of evaluating the machining constants and the dynamic shear flow strengths of bovine bone from orthogonal cutting and drilling tests. The second part of the work arose from investigation into the thermal effects of drilling human bone during which certain trends were observed when comparing feed rate and point angle for fixed values of thrust. Some measure of agreement was found between these two independent pieces of work. Bera and Bhattacharrya's analytical equation for the thrust produced when drilling metals has been modified for anisotropic materials such as bone.

scholarly journals On Howard’s conjecture in heterogeneous shear flow problem

2003 ◽  
Vol 113 (4) ◽  
pp. 451-456 ◽  
Author(s):  
R. G. Shandil ◽  
Jagjit Singh
Keyword(s):  
Shear Flow ◽  
Flow Problem

Linear stability of free shear flow of viscoelastic liquids

1994 ◽  
Vol 268 ◽  
pp. 37-69 ◽  
Author(s):  
J. Azaiez ◽  
G. M. Homsy
Keyword(s):  
Shear Flow ◽  
Linear Stability ◽  
Weissenberg Number ◽  
Inviscid Limit ◽  
Rheological Models ◽  
Mobility Factor ◽  
Wide Range ◽  
Newtonian Case ◽  
Special Limit ◽  
Viscoelastic Liquids

The effects of viscoelasticity on the hydrodynamic stability of plane free shear flow are investigated through a linear stability analysis. Three different rheological models have been examined: the Oldroyd-B, corotational Jeffreys, and Giesekus models. We are especially interested in possible effects of viscoelasticity on the inviscid modes associated with inflexional velocity profiles. In the inviscid limit, it is found that for viscoelasticity to affect the instability of a flow described by the Oldroyd-B model, the Weissenberg number, We, has to go to infinity in such a way that its ratio to the Reynolds number, G ∞ We/Re, is finite. In this special limit we derive a modified Rayleigh equation, the solution of which shows that viscoelasticity reduces the instability of the flow but does not suppress it. The classical Orr–Sommerfeld analysis has been extended to both the Giesekus and corotational Jeffreys models. The latter model showed little variation from the Newtonian case over a wide range of Re, while the former one may have a stabilizing effect depending on the product ςWe where ς is the mobility factor appearing in the Giesekus model. We discuss the mechanisms responsible for reducing the instability of the flow and present some qualitative comparisons with experimental results reported by Hibberd et al. (1982), Scharf (1985 a, b) and Riediger (1989).

Sign in / Sign up

Export Citation Format

Share Document