# education

## Heat Simulation and Analysis of a Railway tunnel

hello eve1,

i m facing some problem while trying to mesh a horse shoe type structure,  when i define the element type as solid 8 node 70 (brick8 node 70) it gives me error saying cannot apply coz it violaets the ASME code or some hting like that....plz help me out wiht what element type has to be defined for the HORSE SHOE type structure...............or whether to define the semi-circular portion seperately (with wat typr ) and the bottom portion seprate.

## Strain Based Fracture Mechanics

Hi!

Im new to this webpage, and hope for some good answers for use in my masters degree within fatigue. Currently Im working on calculating the total life of a gusset specimen using strain based fracture mecahnics. Ive read som articles on the topic, but have some difficulties on understanding the calculations itself. Im using Excel in the calculations. If anyone has an excel-sheet, or other ways of helping me, I would hihgly appreciate it.

Thanks, Sean Angus

## Flow Rate through a gas pipe

Hi I'm trying to work out the following problem

The pressure at the start of a 180Km stainless steel natural gas pipeline is 4MPa and at the end is 2MPa.  If the diameter of the pipe is 0.4m, what will be the gas flow rate through the system? (ignore losses other than friction)

(for natural gas, density = 40 Kg/m3, viscosity = 11x10-6)

This is from an exam paper and at the end of the paper there's a moody diagram with roughness values, the closest to stainless steel is commercial steel and has a k value of 0.045 mm.

## how to use subroutines in abaqus

I will be highly grateful if u will say me how to link subroutines with abaqus....... intel fortran compiler is there.......... how to proceed now????????

## Modal Frequencies

Hi All

How to find the modal frequencies of a wind turbine blade,

-Ravi Talawar

## how to show the stress in the thickness direction when you use the shell element with abaqus

hello,

•      i simulate some process using shell elment, i find the results have big difference between abaqus and lsdyna. the abaqus results always show the stress in the thickness direction is zero. but the lsdyna is not. i don't know why? if some one know that, please give me some suggestions. i heard that the abaqus can not show that stress component. if not, how can i do to calculate that and fill it into the results file (.fil file). thank you!

## Problem with my Abaqus Double Layer Composite Identation Simulation

Choose a channel featured in the header of iMechanica:

Hi everyone,

I currently using Abaqus/CAE 6.8. I currently doing my final year
project about indentation test on double layer composite material. The
top layer of the material is Pasta (elastic) and bottom layer is Gel
(hyperelastic). I manage to simulate the model and completed the
process. The stress of the Gel does not change as it undergoes
deformation. As shown in the clip i attached. Any idea to solve this
problem? Any suggestion is welcomed.. Thanks

Right click the indentation.jpg and save target as....

## Impact analysis of bus body-ansys ls dyna

I am a  B.Tech student at VIT.Presently doing a project on Impact analysis of Bus body using ansys ls dyna.I am getting many errors.If any one is having complete tuturial about above topic, pls send it to me.

## Student

Hi,

I am facing some problem in ABAQUS. How can i use Vumat subroutine and how can i findout sresses.Please help me

## Nonlinear Analysis

Hello,In order to nurture you in an effective manner regarding the Newton-Raphson method I recommend you to consult the excellent treatise of I. M. Smith et al. entitled "Numerical Methods for Engineers ", ISBN-13: 9781584884019.Furthermore this method is elegantly elaborated in Finite Element Formulation in the outstanding book of I. M.

## Detonation &knocking

hello dosto,

i am studying in B-tech 2nd year (mech.) in DCE . I want to know  about detonation and knocking of fuels in detail.

thank you

shankar Gupta

## Help Regarding PhD opportunities

Hi Suo and other guys,

I am Chennakesava. I am new to this site. I have completed my Masters in Mechanical Engineering from Indian Institute of Technology, Kanpur, India. (IITK) . Year of study is 2006-08. My specialization is Solid Mechanics & Design. Right now am working in GE, India. I want to pursue doctoral degree in the field of Dynamics and Vibrations and related issues like, Rotor dynamics, Smart structures, MEMS, Nonlinear dynamics and Chaos. Its kind of a dream to me.

## Query on transformation representing deformation fo space , change of basis and orthogonal nature

Hello All
I am trying to read the text book Tensor analysis by IS Sokolnikoff and stuck in
chaper 1, there is some confusion in my mind regarding orthogonal transformations,
change of basis and and a transformation representing deformation of space.
Please bear with me if my confusions are unfounded.
1) Is is safe to say that transformation representing deformation of space acts on
vectors where as transformations representing the change of basis acts on
components?. (if yes then the following questions are resolved and need not be
looked)
2) Sokolnikoff builds up the reasoning for orthogonal transformations based on
deformation of space (i.e orthogonal transofrmations keep the length of vector