Prof P Myler/K Gregory 2019

BSc Computer Aided Analysis and Simulation – HE 6
Baffle plate design Exercise – Assignment 1 (25%)
Task: Design a suitable profile for a baffle plate to work under pulsating
The plate will be fabricated from stainless steel and have an approximate
rectangular surface area of 3” x 7” as shown in green below. The plate must
have holes through the thickness and total area of 8000 mm2 100 mm2 on
each side for the baffle to work.
The plate suffers a pulsating pressure load of 0.05 atmospheres at a rate of
300 cycles per second.
The Mass limit is 150 grams

 Determine a suitable design of the face manufactured from stainless
steel.
 The plate must be as light as possible so you must determine the smallest
thickness.
 The holes can be any shape or number provided they meet the tolerance
stated.
YOU ARE ALLOWED ONE SHEET OF A4 FOR ANSWERS AND ONE SHEET
OF A4 FOR IMAGES. UPLOAD YOUR .DOC + PART FILE TO MOODLE.
WE RESERVE THE RIGHT TO VIVA. DEADLINE =
Rigidly
fixed here
Pressure face
Can have a curved
profile
Prof P Myler/K Gregory 2019

The material is isotropic and defect free; There are no manufacturing
defects; perfect boundary conditions; no damping or friction; assume thickness
is small; load is evenly distributed: the problem is assumed static (load does not
change with time); Assume shell elements can be used as thickness is small, Non
corrosive environment.______________________________________
2). State the Mass, Thickness, and the Surface Area of your baffle plate (3%)
143g 1.5mm ,Front face surface area 8060mm2 _____________
3) Comment on the mode shapes generated by your analysis (2%)
The working frequency (300Hz) does not match any of the calculated case
frequencies – see figures and tables
below____________________________________________________
_________________________________________________________
4) What is the Maximum Stress and predicted Displacement of your baffle?
(2%) 138 MPa (Yield 292MPa ) 5.4mm (acceptable)
______________ ______________
5) What method of stress analysis have you used and why is this appropriate?
(2%)
Von Mises because the material is ductile and shell elements because the
thickness is small compared to other dimensions_____________
6) Comment on the factor of safety in your baffle (2%)
Max Von Mises stress = 137 MPa; Max Yield stress 292 MPa; therefore factor
of safety = 2.1 : 1
_______________________________________________________

Prof P Myler/K Gregory 2019

7) How does your analysis differ in the way the baffle is secured as opposed to
a real life scenario? (2%)
The fixtures in the analysis are more rigid (perfect) than in the real scenario,
perhaps giving higher frequency values.____________________
8) Suggest possible manufacturing methods for your baffle plate (2%)
Sheet steel processes – Stamping; laser cutting; die cutting;
_______________________________________________
9) You are allowed to include three images ONLY! Choose those that best

or

Prof P Myler/K Gregory 2019

Prof P Myler/K Gregory 2019

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