油桐果实破壳力学特性及主要影响因素研究

Mechanical properties and major influential factors of breaking Tung shell

为研究油桐果实的破壳力学特性和影响因素,通过对油桐果实的物理特征进行测定,开展油桐整果和果瓣压缩试验,研究其破壳力学特性,在此基础上建立油桐果实破壳力学模型,拟合油桐果实破壳力学曲线,并分析破壳过程中的影响因素。结果表明:油桐果实的球度在0.95以上,各个部位外壳厚度基本相同,在进行力学分析时可以将油桐果实简化为均匀薄球壳,油桐果实外壳上的应力状态为二向应力状态。油桐果实的破壳力和所需功耗受油桐果实大小等级和加载部位的影响较明显,破壳力和功耗随着油桐大小等级的增大而增加,顶压方式所需破壳力和功耗明显小于中压方式。

In order to study the mechanical properties and influence factors of breaking Tung shell,physical characteristics of Tung fruit were determined,and the whole Tung fruit and fruit valve compression tests were carried out,the mechanical properties of breaking shell was studied,the mechanical model of breaking Tung shell was established,the mechanical curve of the Tung fruit were fitted and the influential factors were analyzed.The results showed that：the sphericity of Tung fruit is more than 0.95,and the thickness of each part of the shell is basically the same,Tung fruit could be simplified to a spherical shell when its mechanical properties were analyzed,and the stress state of Tung shell was two dimensional stress state.The breaking force and energy of Tung shell is obviously affected by the fruit size and the loading position.Tung‘s breaking shell force and energy increased as its grade increased,and the top loading pressure model requires less breaking force and energy than middle loading pressure model.