Non-Linear Elastomeric Spring Design Using Mooney-Rivlin Constants
A new product design for an engine mount requires very specific nonlinear load deflection curve and geometrical constraints. It was found that a specific geometrical design of an elastomeric material can be used to minimize the cost and complexities in manufacturing this product. Natural rubber was chosen for its transitional properties in shear/compression, low hysterisis, and setting losses in cyclical compression. ANSYS was extremely helpful in approaching the final design and evaluation of performance in all stages of development. Stress/strain tests such as uniaxial tension, biaxial tension, and shear were conducted to refine the nine Mooney -Revlin constants for the ANSYS material model. The final design was evaluated favorably by ANSYS and then was fabricated and tested to yield the desired characteristic curve. The test results were in close agreement with ANSYS predictions especially in the first 70 percent of the maximum deflection.