1. AIRPLANE BEARING BRACKET DESIGN
Lightweight Design 7.50HP MT8006 PROG VT 2016
Master program in Mechanical Engineering
Lecturer: Håkan petersson
Zoelfikar Elghoul Shopin John
Challenge Requirements and Work Envelope

2. Contents
Lightweight Design 7.50HP MT8006 PROG VT 2016........................................................................... 1
1. Introduction..................................................................................................................................... 3
2. Problem Statement ............................................................................................................................. 3
3. Model preparation in inspire........................................................................................................... 5
4. Load case ........................................................................................................................................ 5
5.Contact Information......................................................................................................................... 6
6.Connector Definitions ...................................................................................................................... 6
7. Material properties ......................................................................................................................... 7
8. Design improvements during optimization..................................................................................... 7
9. Optimization results ........................................................................................................................ 8
10.Yield stress...................................................................................................................................... 9
11.Von mises ..................................................................................................................................... 10
13.Major prinicple stresses after redsian results.............................................................................. 11
13.Vom ises stress ............................................................................................................................ 12
14.Yield stress.................................................................................................................................... 13
15.Manufacturing.............................................................................................................................. 14
........................................................................................................................................................... 14
15. Conclusion ................................................................................................................................... 14

3. 1. Introduction
In this task we will use the software inspire 2015 release which has faster geometry functions
with an updated user interface and expands the scope of complexity of problems can be
addressed, Inspire 2015 version has a new added features from the users include fasteners,
joints and contracts, this features will enable us to quickly model, analyze and optimize our
assemble the brackets. The question is why we will use inspire
 Saving 23 % weight compared to initial design
 Casting constraints to ensure manufacturability
Inspire design process
Inspire design process Start with the solution and shorten time to market
2. Problem Statement
ALCOA Company launched a Design Contest with the objective to obtain a Bearing Bracket
and behave similarly to a component manufactured with traditional Aerospace processes such
as machining.
The envelope design requirements to design a bracket that could withstand the three load
cases given and do not exceed the envelope highest strength weight ratio possible, the design
Envelope can be seen in

4. Figure 1 Design Envelope
The Design takes the best practices currently used. Fastener Edge is considered with smoother
transitions between the regions and avoided sharp edges and stress raisers.
Final Design is shown in Figure 2 and has a mass of 228 grams
Figure 2 Final design

5. 3. Model preparation in inspire
Bracket support Plate contact zone type bonded
Rigid elements ( 4 bolt connection)
4. Load case
Horizantal Load 1250
lb
Inclined Load 1875lb Vertical load 2500 lb

6. 5.Contact Information
Contact Contact Image Contact propertiers
Bracket _support
plate contact
contact zone type
bonded
Bracket _support
bearing bracket
contact zone type
bonded
6.Connector Definitions
Pin_Bolt_Bearing Connector
Contact Contact Image propertiers
Bolt _bracket
_support Plate
Contact
4 fasteners
Aligned hole
fasteners automatic
Inspire 2015
enhance

7. 7. Material properties
Part Image propertiers
Bracket 15-5PH per
AMS5862
Elastic Modulus (𝐸) =
29,000 KSI = 200,000
MPa = 200 GPa
Poisson Ratio (𝜈) =
0.27
Yield Stress (𝜎𝑦) =
145 KSI = 1000 MPA
Density (𝜌) = 0.283
𝑙𝑏/𝑖𝑛3 = 7833 𝑘𝑔/𝑚3
Material is assumed
to be linear elastic
Fasteners ( 4
Bolts)
Part is fastened by
four high strength
bolts (#10-32)
Support
Part Image properties
support Plate Support
8. Design improvements during optimization
During the optimization we had many problems so we had realized, there could be a couple of
changes that we could suggest in order to improve the overall Design of the bracket, for
example:

8.  Have the freedom to move the fastener footprints at least +/- 0.100in. In order to avoid
the D-Nose shape like at the end of the bracket and have a straight run out,
 Modify the enveloped provided where the bearing arm suddenly changes cross
section. See picture below.
Figure
 Used bolts/hi-lites for#10 should have around .5 clearances for the head.
 A #10(3/16”) Hi-Lite Tension head has a head diameter of 0.357-0.377 in.
9. Optimization results
Results from inspire 2015 after optimization
Results from inspire 2015 after optimization Fit smoothing

9. 10.Yield stress
Load case 1 94,1% Load case 2 100,9%
Load case 3

10. 11.Von mises
Load case 1 Load case 2
Load case 3

11. 13.Major prinicple stresses after redsian results
s
Load case 1
1.410e+005
lbf/in2
Load case 2
1.331e+005
lbf/in2
Load case 3
1.289e+005
lbf/in2

12. 13.Vom ises stress
1.320e+005
lbf/in2
Load case 2
1.265e+005
lbf/in
Load case3
1.289e+005
lbf/in2

13. 14.Yield stress
Load case 1
Yield stress
91%
Load case 2
Yield stress
87,2
Load case3
Yield
stress88,9%

14. 15.Manufacturing
The bracket is intended to be manufactured by additive manufacturing process.
Recommended Print Direction see figure
Figure.3 print direction
15. Conclusion
The Bracket is sized considering the best practices in inspire 2015 below are the
conclusions.
 The stress plots for static cases show a stress of 100.9 % case load 2(more than Yield of
100%). This is due to the stress concentration effect. Ignoring the high stress areas due to Kt,
there is no yielding of the material for any of the static load cases.
 Critical details have to be sized for cyclic loading. Sizing the component to Yield with
presence of a stress concentration is highly conservative.
 If minor modifications could be done to the envelope provided, we could further optimize and
reduce the weight of the bracket as previously stated
 Mass of the original model was 1,833lb. Modified model mass is now 0,502 lb. (228
gram)