同轴差速式酿酒葡萄离心破碎机设计与试验

Design and Experiment of Coaxial Differential Speed Centrifugal Crushing Device for Grape

摘要:

针对传统离心式酿酒葡萄破碎机作业时破碎度不均匀且破碎率重复性较低，导致葡萄果皮破碎率和出汁率不稳定影响后续浸渍发酵质量，设计一种同轴差速式葡萄离心破碎机，通过导流叶轮分流并导流葡萄粒群、冲击叶轮撞击破碎葡萄。构建了导流、冲击破碎过程中的葡萄受力模型，分析确定了影响破碎性能的关键结构参数。采用EDEM离散元仿真建立了破碎机和葡萄互作仿真模型，并进行三因素三水平正交试验，分析了导流叶轮转速nd、冲击叶轮转速nc和喂入量wr对分流不均匀性系数和冲击稳定指数的影响，确定了最优工作参数组合：导流叶轮转速nd为80r/min、冲击叶轮转速nc为600r/min、喂入量wr为6kg/s。酿酒工厂内机械性能破碎试验结果表明，葡萄平均破碎率和出汁率分别为96.37%和7.05%，相应变异系数分别为1.23%和19.76%，相较于传统破碎机，破碎率变异系数降低58.3%，出汁率变异系数降低23.4%，整机作业效果满足葡萄酒酿造工艺要求。

Abstract:

The first critical quality point in the wine making process is grape breakage. The grape crushing rate, juice yield rate, and the repeatability will affect the taste and flavor of wine production. The traditional centrifugal crushing machines used in winemaking often result in uneven crushing and low repeatability of crushing rates, leading to instability in the skin rupture rate and juice yield, affecting the quality of subsequent maceration and fermentation processes. To address these issues, a coaxial differential-speed centrifugal crushing method for winemaking grapes was designed, utilizing a guiding impeller to divert and direct the flow and a striking impeller to impact and crush the grapes. A mechanical model was constructed for the feeding process, flow guiding, and impact crushing to analyze and identify the key structural parameters affecting crushing performance. A model was established by using EDEM discrete element simulation to simulate the interaction between the crusher and the grapes. A three-factor, three-level response surface experiment was conducted to analyze the effects of guiding impeller speed, striking impeller speed, and feed rate on the flow uniformity and crushing stability coefficient. The optimal operating parameter combination was determined as follows: guiding impeller speed (nd) was 80r/min, striking impeller speed (nc) was 600r/min, and feed rate (wr) was 6kg/s. Performance crushing tests conducted at the factory revealed that the average crushing rate and juice yield were 96.37% and 7.05%, respectively. The variation coefficients of the crushing rate and juice yield were 1.23% and 19.76%, respectively. Compared with traditional crushers, the variation coefficient of the crushing rate was reduced by 58.3%, and that of the juice yield was reduced by 23.4%. Overall, the operational performance of the coaxial differential-speed centrifugal grape crusher met the requirements of winemaking processes. This research could improve the mechanical crushing performance of wine grapes, furthermore enhancing the quality of wine production. The research result can provide reference and guidance for the improvement of fruit crushing machinery in the relevant fruit wine brewing process.