Method of calculating mass moment of inertia of a crankshaft Essay Example

method of calculating mass moment of inertia of a crankshaft

Describe a method for calculating the mass moment of inertia of a physical crankshaft such as the one shown in the image above. Please describe your fully experimental method.

Solution

To determine the mass moment of inertia of a crankshaft, it is required to calculate the I for each of the sections in crank shaft. Assuming that the sections have equal characteristics i.e. equal lengths and widths, the mass moment of inertia of a single section can be determined then related to the rest of the sections. Each of the sections in the crankshafts is made up of a thin with its rotating about the axis. The following steps describe the process of determining the mass moment of inertia of a single Rod.

Let each section have a mass, m and length L. Let dx

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The wings of the crankshaft are treated as a disk being rotated at the edge. Taking the radius of the disk as R, and a Mass of m, the derived equation for the moment of inertia is

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Therefore, the mass moment of inertia of a section is

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Let the number of sections of the crankshaft be n, the mass moment of inertia of the crankshaft is

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