Palm nut cracking under repeated impact load

Abstract

Cracking a whole palm nut under repeated impact load, with the object of minimizing kernel breakage, was modeled and tested. The models were based on the conservation of energy impacted on the nut by a falling weight, or the kinetic energy of a moving nut and the strain energy required in fracturing the nutshell. One of the two models predicts the falling height required to crack a nut, in terms of stiffness, maximum deformation and size of the nut and the load cycles. The second model predicts the hurling speed required to crack a nut, in terms of stiffness, maximum deformation, mass and size of the nut and the load cycles. Experimental verification, which is in good agreement with the theory showed significant reduction in kernel breakage when palm nuts were subjected to low but repeated impact.