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JOURNAL OF INTERDISCIPLINARY RESEARCH
The maximum values of stress are shown in Table 3, which also
contains the value of the calculated safety factor. Safety factor
does not fall below the permissible value of 1.5 in either load
case, so construction can be considered satisfactory for this load
state.
Part
Equivalent von
Misses stress [MPa]
Safety factor
Inner shell
244,85
1,55
Outer shell
129,99
1,57
Table 3 Load case 1, comparison of calculated values and
allowed values (Source: authors)
5.4.2 Results for load state 2
In the second load cases, it was not possible to use half the
symmetry due to asymmetrical nature of the load. In
computation, the whole model was used. The maximum stress
value of the outer shell is in the front part the shell (Figure 8).
The maximum value of stress in inner shell was again in the area
of the filler neck (Figure 9).
Figure 8 Load case 2 - stress distribution on outler shell (Source: authors)
Figure 9 Load case 2 - Longitudinal crossection stress, distribution on inner shell (Source: authors)
Table 4 shows the maximum stress for inner and outer shell with
a factor of safety that exceed the value of 1.7, which means that
in this load state in terms of strength it produces some reserve.
Part
Equivalent von
Misses stress [MPa]
Safety factor
Inner shell
218,36
1,74
Outer shell
119,06
1,72
Table 4 Load case 2, comparison of calculated values and
allowed values (Source: authors)
5.4.3 Results for load state 3
In the third type of load the half symmetry of model was again
used. Stress distribution can be observed on the outer and inner
shell, the maximum stress occurred again in the front part of the
outer shell (Figure 10) and in the area of filler neck in the inner
shell (Figure 11).
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