Download presentation
1
Workshop :Bicycle Frame Design (Optimization)
University of Puerto Rico at Mayagüez Department of Mechanical Engineering Workshop :Bicycle Frame Design (Optimization) Modified by (2009): Dr. Vijay K. Goyal Associate Professor, Department of Mechanical Engineering University of Puerto Rico at Mayagüez Thanks to Josymir Lopez Ferrer , enrolled in INME 4058 section 2008
2
Problem Description This is a simple static analysis of a frame of bicycle using a hollow aluminum tube. The schematic dimensions of the bicycle are shown in the figure 1. Initially, the flowing cross-sectional dimensions are used for all frames: Outer diameter φ = 25mm and Thickness t =2mm . The material properties of aluminum are: Material Properties Values Young’s Modulus (E) 70 Gpa Poisson’s Ration (ν) 0.33 Density (ρ) 2,580 kg/m3 Ultimate Tensile Strength(σU) 210 Mpa Elongation at Break 10 %
3
Problem Description (cont.)
Even if the bike is under the dynamic loads, only the static design criteria is considered here: due to vertical bending. Vertical bending test: When an adult rides the bike, the nominal load can be estimated by the vertically downward load of 600N at the seat position and a load of 200N at the pedal crank location. When a dynamic environment is simulated using the static analysis, the static loads are often multiplied by a certain “G-factor”. In this design project, use G = 2. Use ball-joint boundary condition for the front dropout (1) and sliding boundary condition for rear dropouts ( 5 and 6 ).
4
Problem Description (cont.)
We want to optimize the bars. For this reason, we are assuming that the following bars will have the same cross-sectional areas: bars 1 and 4 will have the same cross-sectional area, defined by real constant 1 bars 2 and 3 will have the same cross-sectional area, defined by real constant 2 all other bars will have the same cross-sectional area, defined by real constant 3 .
5
Starting ANSYS From your desktop:
Click on: START > All Programs > ANSYS > ANSYS Product Launcher. Here we will set our Working Directory and the Graphics Manager
6
Working Directory Setup
Select the Working Directory and type the name of work shop on Job Name.
7
Graphics Setup Click the button: Customization/Preferences.
On the item of Use custom memory settings type 128 on Total Workspace (MB): and type 64 on Database (MB): Then click the Run bottom. * This setup applies to computers running under 512 MB of RAM
8
Go to customization preferences and choose custom memory settings and give values of 128 and 64 for the total workspace and database memory respectively. Click Run to start
9
ANSYS GUI Overview This is ANSYS’s Graphical User Interface window.
10
Step 1: Build the model We have two option:
We can fun the previous tutorial and save the output in VerticalBendingTest.txt Or, read the VerticalBendingTest.txt (it runs the tutorial directly) .
11
Step 2: Go to Design Optimization
Go to Design Opt> Analysis File> Create Assign… File name is: VerticalBendingTest.txt Now Go to utility menu and read the VerticalBendingTestOptimization.txt file (read input) Go to Design Opt> Design Set>List (choose ALL sets). This gives you the various iterations .
12
Step 3: Now use this model
From this point on you can use this model to perform all other analysis. .
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.