Abstract:
A three-dimensional method of stress analysis using
finite element techniques is presented for determining the
stress distribution in centrifugal impellers. It can treat
all of the three types of loading possible in an inpeller,
viz centrifugal, thermal and fluid. The method has no known
limitations with regards to the geometric factors such as
asymnetry of disk, blade curvature, presence of a cover disk
or shroud, single or double sided impeller etc.
A comparison of results with available experimental
photoelastic results is presented with good agreement. The
problem of the inter-blade bending effect, on the stress
characteristics of an impeller, with relevance to the number
of blades is studied in some depth. An insight into the
effect of blade curvature on the stress characteristics of
an impeller is also achieved.
As an extension of the above work, a method is proposed
for the analysis of the dynamic, behaviour of impe1lers,
achieving a reasonable degree of success, particularly
considering the limited period of time that was available
for such an exercise.