Written by Vijay Mali
Tuesday, January 12, 2016
Design and CFD simulation of butterfly valve in 40 minutes - Onshape & simulationHub Integrated Apps
By
Vijay Mali
“The power of CFD simulation in hands of designers – whenever & wherever they need it” is the part of simulationHub’s
vision. In today’s era of product development, the first stage is to convert conceptual idea into its computer representation
or 3D CAD model. This CAD model is then migrated to downstream domains like rendering, CAM, 3D printing, CFD, FEA and
many more.
CFD simulation is one piece of puzzle in complete product design cycle. Simulation stage needs CAD model as an input. Along
with simulation tool, designer needs CAD tool to design and optimize the product. Following is what I think as a product
design cycle when it comes to design and optimization of the product for flow and thermal performance.
Designer and Innovation
To connect the dots and to give true power of “virtual realization of product” to designers, simulationHub
and Onshape has come together. Onshape is full-cloud 3D CAD system. It gives designers an access to all that is required
to convert conceptual idea into a 3D CAD model. simulationHub is a cloud based CFD app which gives power of CFD simulation
to designers.
simulationHub is now available as an integrated app within Onshape environment. It has seamless integration with Onshape
CAD data which recognizes and propagates design changes all the way to CFD simulation process. This seamless integration
allows designers to carryout quick design iterations based on CFD simulation results.
Onshape and simulationHub integrated app
An Idea to CAD
I thought of getting my first experience on Onshape CAD and simulationHub CFD integration. This blog is all about my experience
on using this integration.
I am not an expert user of Onshape or any other CAD software. My knowledge and work experience on creating CAD model is bit
limited. So I thought of working on simple design concept and hence selected butterfly valve design. With some knowledge
of what is sketch, what is part, what is extrude, revolve feature, I was able to generate the CAD model in 20 minutes
using Onshape. Although, majority of my time was consumed in “beautification of the model”, it was fun converting my
conceptual butterfly design into 3D CAD model. The model is not that elegant and you might see some modeling errors in
live demonstration, but idea was to convert conceptual design in a relatively good and usable CAD model.
CAD model prepared on Onshape
After creating CAD model, I wanted to do CFD simulation for different angle of openings. To generate the model at different
opening conditions, single rotation attribute was defined for valve.
Valve rotation attribute
The total valve opening is from 0 degree (closed condition) to 90 degree (fully open condition). Following are the conditions
for which I wanted to see the performance in terms of flow characteristics and pressure drop for my design:
Valve rotation attribute
CAD to CFD
To do CFD simulation at 30 degree opening, valve geometry is rotated by 30 degree. simulationHub is available as integrated
app within Onshape. The application is added using “Add Application” option.
Adding simulationHub app in Onshape
A new simulationHub tab is added within Onshape environment. Once the simulation name is given, the valve geometry with 30
degree opening is transferred to simulationHub. Further process of extracting fluid volume, setting up boundary conditions
and simulation run is followed in simulationHub tab. For each opening angle, the simulation process took about 4 minutes
of time. Same procedure is followed for other openings.
30 Degree
45 Degree
60 Degree
75 Degree
The process of CAD modeling and simulation for four different angle of openings took about 43 minutes. Below is the video of
live demonstration on how design and simulation for butterfly valve is done using Onshape and simulationHub.
This video is a live demonstration of creating 3D CAD model using Onshape and CFD simulation using simulationHub integrated app. This covers how to create butterfly valve geometry using Onshape and do CFD simulation using simulationHub. CFD simulation for four different opening angle 30, 45, 60 and 75 degree are conducted. CFD results are presented with quantitative values like velocity and pressure. The qualitative data like flow lines, velocity and pressure contours are available on cut sections.
NOTE : The video demonstration uses older version of Generic Simulation app.
So this is how it went. Based on my previous CFD experience and working on this integration, following are my strong feeling
about it:
- Both Onshape and simulationHub being fully cloud, it is really anytime and anywhere
- It’s seamless integration allowed me to propagate design changes all the way to CFD
- Based on my previous experience in doing CFD simulation for similar product, I felt it’s really quick and easy and truly made for designers
- This is definitely made for designers with really simple workflow
As a designer, I felt few aspects are missing in this integration:
- Intelligent setup: If there are any design change, it was propagated only up to geometry stage in simulation. It would be great if we can propagate that information all the way to CFD results
- Design variations: It would be great if we can see all the variations at one place. Maintaining the same camera position, highlighting the design changes, highlighting the CFD results different would be great tools for designers
SIGN UP and Try
Both Onshape and simulationHub has full capability free versions available. Create your FREE Onshape and
simulationHub account. To use simulationHub inside Onshape as integrated app, you need to add simulationHub app to your Onshape account.
Written by Vijay Mali
Comments
Recent posts
