ME450 Project

Gearbox Analysis  ME450 Finite Element Analysis  Fall Semester, 2007  Prof: Dr. K. Nematollahi  Team Members  Aaron Huesman  Jae Shin  Kelly McCormick

Objective Perform structural analysis of two competing designs of a machined aluminum gearbox casing.

Applicable Theory {F} = [T][K][T] -1 {U}

Introduction  Two competing designs  Webbed  Non-webbed  Previous choice based on ease of machining  Performing structural analysis to confirm choice

Non-Webbed

Webbed

Unigraphics Model

Forces

Ansys Model Details  Model reduced to simplest form  One half of casing used (symmetry)  Gears removed  Bearings simulated  Aluminum alloy material for case  Brass material for bearing volumes

Ansys Model Solid Cylinders Simulate Bearings Substitute Bearing Volumes

Boundary Conditions

Boundary Conditions Cont…

Element Type  Utilized ten-node SOLID92 tetrahedral elements  Ideal for complicated solids with curved boundaries

Meshing  Automatic meshing option

Analysis  Deformation study  Von-Mises Stress study Consistent boundary conditions and forces applied.

Deformation Distribution Non-Webbed Webbed Max: 5.17E-4 in.Max: 5.00E-4 in.

Stress Distribution Non-Webbed Webbed Max: psiMax: psi

Results  Non-Webbed 1. Max Deformation = in 2. Max Stress = PSI 3. Mass = lbm  Webbed 1. Max Deformation = in 2. Max Stress = PSI 3. Mass = lbm  %Change 1. Max Deformation = -3.3% 2. Max Stress = -24.5% 3. Mass = +2.7%

Impact Statement  Reduced chance of a failure 1. Reduces potential waste of material 2. Reduces potential environmental contamination 3. Reduces potential injuries (Robust design)

Conclusion  Webbed design is superior. 1. Less stress 2. Less deformation 3. Easier machining 4. Minimal change in weight

Bibliography [1] Moaveni, Saeed. “Finite Element Analysis” Theory and Application with Ansys – 3rd Addition, Pearson Education, Inc., Pearson Prentice Hall, Upper Saddle River, NJ 07458, 2008.

Questions