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Emboss of an image with inventor

Usually to add an binary image as a logo to inventor is a process of converting the image to eps and then tranfer that file to autocad and the to inventor.

Seismic Tank Sloshing

My first step was to get the accelerations in X,Y,Z for a specific earthquake.

Rice Quality Control with Matlab

Aims and Description Develop a simple application to identified specific visual properties like · Size measurement · Color Measurement

Design Of An AUV(Inventor/Flow simulation solidworks)

In robotics the most complicate step is the selection of motors and battery. the weight of the battery is the principal component of the mass of a robot. In the process to design AUV i decide to start the design with the selection of thrusters with a high drag force of 1.5 and a speed of 3 knots.

Tuesday 26 May 2015

HOW TO GET A CAE SOFTWARE FOR YOU COMPANY?

Imagine this situation, you arrive to a company that want to start to use FEA and you are the only engineer in the company that has ever use FEA software. What do you do? Where do you start?
It is a very difficult situation. There are some guides over the network of how to choose the best software. How to test the software but they do not take in account something that the management department is going to ask you always, how much it is cost?
I will like to give a little of clarity over what I did in the last year when I started the department of FEA in my actual company.
I’m going to give a little background, I was hire to run FEA for a company of Non-destructive testings for oil storage tanks under the norm API 579 and API 653.
I arrive to the company and I didn’t have hardware or software to work with it.
On this case I have to study what types of simulations will be required for my requirements, as always google is our friend. In a week I could establish that

  1. linear structural, 
  1. nonlinear structural, 
  1. thermodynamics    
  1. and transient simulation

will be required for my needs.

Then there is time to call some suppliers and write mails asking for quotations.
You search the web for the CAE software providers and get a lot of names
On this opportunity I contact:


  • Solidworks
  • Ansys
  • Comsol
  • Autodesk
  • MSC Nastran


The ones that I forgot or I knew they will expensive

  • Abaqus
  • Midas NFX
  • And others


(If you know of one please let me know is good to know of other software)
Now the interesting part
1.       How are you going to test this companies?
For testing the companies I decided that I will email them asking for a quotation and explaining them my needs, sector of work and type o simulation that I usually will carry on. As usual they will answer you that they will want to do a presentation of the software and talk to you in a meeting. ”never take a decision based in a power point presentation”.
For the meeting are some clear points to have in mind.
If they arrive without a quotation or they start to talk about prices depending of company size or they denied to give a clear quotation. You can start to put bad marks to that company.
Ask :
How is the technical support?
How do you get help with a project?
Where do you learn the software?
How is the license?
How do you scale your license?
Can they help you with a license upgrade for a limited time if you have a different project?
2.       How are you going to test the software?
This part is easy create a similar model to what you are going to do usually and test the different modules that you are going to be provide. If you have any problem test the support from the company it doesn’t matter if you do not have question ask them dumb questions. You have to test the support.

I imagine that you want to know how this companies rank on this aspects in my case:

ANSYS
The favourite company from my boss. All engineers have some knowledge of ANSYS or they had hear about it. Let me explain how ANSYS works in a corporative level. You do not acquired a license from ANSYS but from one of the subsidiary companies. If you are not a big company you will not receive support directly from ANSYS but from the subsidiary. One of the things that I hate is that subsidiaries most of the time are a competitive company of your company. How?, in oil and gas industry you fight for a contract with other companies they offer to do the service with ANSYS but they do not have ANSYS, they contract this subsidiaries to do the job for them.
Some subsidiaries have prices depending of the company and the support to get you running is not good. You have to take a course with them and if you have question over a particular problem is in your own if you do not get each year the support license. The price is expensive vs other companies with the same package. The software works well over the test but they were eliminated for the low technical support over time.

COMSOL
I like this company, I didn’t know how to use the platform, the price were under ANSYS cost and the expandability was great. They offer help for get me running but that was the part where they fail. I create a model and as soon I exported the model to COMSOL I get a problem I wrote the mail to the sales person that was helping me but I never get an answer. I assist to a meeting to learn the software but the representative was a little rude with bachelor student that were in the same room. I tried to consider the software but they were eliminated because I couldn’t test the software.

Solidworks Simulation
This company surprise me, the software behaves well, and the test was smooth and very easy to learn. I had used the cfd module before but the FEM module was equally great to use .The online communities give you all the support to do any project and the technical support from DSS assault is really good. At the end was a decision of market placement. My boss didn’t like the name and it was a fear that the client will not like the brand.

Autodesk Simulation
The old ALGOR software lives inside of this software, as an inventor user was very easy for me to adapt to the use of the simulation software. The online support through the forum is excellent with the support of expert user and members of Autodesk official support. I believe that they understand that student need support to learn their software. The technical test was not so smooth I have to twice some thinks but and the end the results were good. The price was good for the company and together with solidworks were my recommendations to be acquired.

How do you expose your opinion to your boss

You have to calculate rate of return. How many project do you have per year how much is going to be recover per project and you can know how much is your return per year. If is positive your boss is going to be happy and that is all what he is interested in.








Tuesday 7 October 2014

Seismic Tank Sloshing

This is a duplicated post from the forum of autodesk cfd simulation 

I work for a company that do simulations for oil tanks...In the last days we test CFD simulation because we wanted to do the simulation of sloshing of a tank when a seismic load is applied.
A natural frequency study is not enough for this simulations and we require a more precise simulation.

 As many people ask in the forum of how to setup free surface simulations and I believe that the tutorial of CFD is not clear enough.
I'm Going to explain how I did the simulation.
My first step was to get the accelerations in X,Y,Z for a specific earthquake.
I download the files from http://peer.berkeley.edu/smcat/search.html I suggest these files http://peer.berkeley.edu/svbin/Detail?id=P1083 you have to download the accelerations of UP,NS,EW they are equal to X,Y,Z.
The file are read from left to right and up to down with a time between measure of 0.005 second and the values are in g. to use this data in CFD it is need to translate the information into a simple column and mm/s3. I am attaching a small xls that i wrote to process the data.(to paste the data use the paste assistant of excel) I create the model in Inventor and exported to autodesk CFD.

I set the fluid as diesel.
I set the upper boundary as 0 pressure surface and the low volume as initial height of fluid.
Know we can setup the free space model.
Solve/physics/free surface

set the gravity in the direction you want in my case is 0,0,-1 and I set the tables of accelerations . The first step to set the tables is to save a blank file . that file is going to be your base *.csv file where you are going to paste the yellow data of my excel after editing that file in excel you can import the file to CFD
You have to do the same for all axis. place the files inside of the same folder of the design number in my case design 1 folder.
The time step size has to be less than 0.005 s or the simulations is not going to be good.

The only question that i couldn't solve is how to obtain a good surface mesh between the volumes i want a initial flat surface.
However the results are good



Friday 11 April 2014

123D CATCH

 

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