双向深割过渡圆角对提高曲轴主轴颈疲劳强度的研究

基于ANSYSworkbench软件,根据中国船级社《钢质海船入级规范》柴油机曲轴疲劳强度评定规则,对某船用中速柴油机的曲轴进行了有限元模拟分析及疲劳强度安全系数计算与评估。为了提高曲轴疲劳强度,提出了曲轴主轴颈双向深割型过渡圆角方案。分析了轴向及径向深割凹槽深度变化对局部应力大小、应力集中系数及疲劳强度安全系数的影响;明确了最佳双向深割型过渡圆角结构参数,使曲轴主轴颈疲劳强度安全系数得到了较大提高。

Study on the Improvement of Fatigue Strength of Crankshaft byBidirectional Deep Cutting Transition Fillet

Based on ANSYSworkbench software, finite element simulation analysis as well as fatigue strength safety coefficient calculation and evaluation were conducted on the crankshaft of a certain marine medium-speed diesel engine according to the fatigue strength assessment rules from "Rules for Classification of Sea-Going Steel Ships" by CCS. In order to improve the fatigue strength of crankshaft, the solution using bidirectional deep cutting transition fillet for main journal of crankshaft was proposed. The influence of depth change of deep cutting groove in both axial and radial directions on local stress, stress concentration coefficient and fatigue strength safety coefficient was studied. The structure parameters of the optimal bidirectional deep cutting transition fillet are determined, thus largely improves the fatigue strength safety coefficient of crankshaft main journals.