XANSYS Message: 10 [Go back to message list]
[bookmark on del.icio.us]
No rating yet
Subject: Re: Hex & Tet elements
Author: John Swanson
Date: 1998-12-14 10:39:00With mid-side node elements (10 node tet, 20 node bricks), the
results should be the same (very close) for the same nodal density.
The tet mesh will have more nodes because of the nodes in the
center of the faces and in the center of the brick, and therefore will
be somewhat more accurate.
The advantage of fully automatic mesh generation offered by the
tet elements normally outweighs the additional time the solution
might take (computers are cheaper than people, and time is always
critical).
John.Swanson
> -----Original Message-----
> From: Johan Hsu;(W)439-7624;1E09-100 [SMTP:hsujx@o...]
> Sent: Monday, December 14, 1998 9:32 AM
> To: xansys@o...
> Subject: [xansys] Re: FW: Hex & Tet elements
> From: "Johan Hsu;(W)439-7624;1E09-100"
> I don't have my book with me right now but I do remember that the Hex
> elements
> produce better result than Tet elements only when the edges of the
> Hex's form at
> right angles.(4 degree either side?) In the other word, if the
> element is
> distorted 3 Tet's produce better result than a single Hex. Correct me
> if I got
> it all wrong.
> J. Hsu
> > Date: Mon, 14 Dec 1998 10:20:40 +0100
> > From: Roberto Muccini
> > To: xansys@o...
> > Mailing-List: list xansys@o...; contact
> xansys-owner@o...
> > Delivered-To: mailing list xansys@o...
> > List-Unsubscribe:
> > Mime-Version: 1.0
> > Content-Transfer-Encoding: 7bit
> > Subject: [xansys] Re: FW: Hex & Tet elements
> > From: Roberto Muccini
> > Ng Siu Wai, Alex wrote:
> > > From: "Ng Siu Wai, Alex"
> > > -----Original Message-----
> > > From: Binxin Wang [SMTP:wangbinxin@h...]
> > >
> > > Sent: Friday, December 11, 1998 10:59 PM
> > > To: feusers@m...
> > > Subject: Hex & Tet elements
> > > Dear all,
> > > Can any one there provide any reference explaining theoretically
> why linear
> > > Hex elements produce better results than Tet elements.
> > > Thanks in advance.
> > > Regards.
> > > Binxin
> > FE routines calculate results in a fixed number of points for each
> > elements (Gauss points) then average across the element. The
> accuracy of
> > results is function of the number of this points (then the
> interpolation
> > function order): e.g. if you have two points you can use a linear
> > function, if three a quadratic, ecc.
> > This are only few words about this matter. You can find exhaustive
> > explanation in every basic FE book.
> > For example:
> > Cook et al. "Concepts and applications of finite elemnt analysis",
> > second edition, John Wiley and Sons, New York 1981
> > Bathe et al. "Finite element Procedures in Engineering Analysis",
> > Prentice Hall, Englewood Cliffs 1982
> > Zienkiewicz et al. "The finite element method", Mc-Graw Hill
> Company,
> > London 1977
> > Hope this helps
> > Roberto Muccini
> > Muccini Roberto
> > Laboratorio di Tecnologia dei Materiali tel.
> +39-(0)51-6366864550
> > Istituti Ortopedici Rizzoli fax. +39-(0)51-6366863
> > via di Barbiano 1/10
> e-mail:muccini@t...
> > 40136 Bologna, Italy
> Johan Hsu, MSME
> FEA Analytical Engineer
> SIEMENS Westinghouse Power Corp.
> Orlando, Florida