{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

CFD lecture 24

# CFD lecture 24 - Computational Fluid Dynamics Lecture 24...

This preview shows pages 1–3. Sign up to view the full content.

Computational Fluid Dynamics Lecture 24 General Curvilinear Coordinates Computing flow around complex geometry is better accomplished by solving the PDE’s of the N.S. equations in a generalized coordinate system. Transfer to Cartesian grid. This causes the PDEs to be more complex but improves the treatment of the boundary conditions. This permits grid lines to be concentrated in parts of the physical domain where strong gradients occur. Complications: Changes PDE’s. - additional terms, x ξ , etc. usually discretized, and introduce additional errors. Physical space ( ) , , , x y z t Computational space ( ) , , , ξ η ζ τ Want a unique – single valued transform - ξ grid lines don’t cross (similar to no caustics). 1

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Consider first the 1-D transform problem. Physical space clustered physical uniform computational grid A variable mesh is often used to cluster computational nodes, in a no-slip boundary layer. One stretching function is This would be ideal for a laminar boundary layer, but a turbulent boundary layer may benefit from an even stronger clustering of grid points near the wall. 2 on 0 1, and are constants. z a b a b ζ ζ ζ = + A second commonly used analytical transformation function is: 1 ln 1 1 1 1 ln 1 z h z h β β ζ β β β + − + = <
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern