The follow
ing post has two assignments namely;
1.Ethics and Financial Reporting
Exam
ine the three potential conflicts of
interest that can take place dur
ing the audit
ing process.
2.Finite element analysis (FEA)
Figure 1 shows a cantilever beam that is fixed at one end and a load of 60 kg
initially at 50 mm (b)
from the free end of the beam. The beam has a rectangular cross-section with a thickness of 2 mm.
The beam is made from a 2000 series alum
inium alloy (AA2024-T351) and its behaviour is
elastic-plastic accord
ing to the data provided below.
You can assume the follow
ing
information:
Yield strength = 324 MPa
UTS = 469 MPa @ eng
ineer
ing stra
in of 19%
Beam thickness: 2.0 mm; b = 50 mm
Young’s modulus, E = 73 GPa
Poisson’s ratio, υ = 0.33
Figure 1: Cantilever beam arrangement
A. Us
ing a suitable FE software such as ABAQUS (or an alternative commercial package),
perform a f
inite element analysis to determ
ine the maximum stress and maximum vertical
deflection experienced by the beam. Where appropriate, employ suitable simplifications,
assumptions or approximations for your model and ensure that boundary conditions,
load
ing and material properties/behaviour are correctly described. A number of simulations
are to be carried out by utilis
ing different number of cont
inuum (solid) type elements
in the
range listed below
in order to
investigate the effect of element size and mesh density on the
output measures:
a) 30-60 b) 160 – 300 c) 600 – 1200 d) 2500 – 6000 e) ~9,000
Plot graphs of maximum stress and maximum vertical deflection of the beam versus
number of elements
in the model. Record the analysis time required for each of the models.
Validate the predicted maximum vertical displacement from your model us
ing analytical
stress analysis calculations.
B. Formulate another FE analysis on the same structure but this time with a 140 kg load applied at
the 50 mm from the free end of the beam us
ing the best mesh density derived from Section A.
Evaluate the results accord
ingly and comment on any issues you may observe.