横置式甘蔗收获机排杂风机叶轮气动特性分析与参数优化

Aerodynamic Characteristics and Parameter Optimization of Sugarcane Chopper Harvester Extractor Impeller on Transverse

摘要:

排杂风机是切段式甘蔗收获机的核心部件之一，其性能对甘蔗收获机含杂率起到了至关重要的作用，而叶轮是排杂风机的核心部件，其气动性能与排杂效果密切相关。针对横置式甘蔗收获机排杂风机叶轮性能不足、影响排杂效果的问题，以叶轮为研究对象，研究轮毂类型、叶片安装角β、叶片数Nb、叶轮无量纲面积G、叶片夹角γ对风机气动特性的影响及其机理，并以提高风机全压为目标，通过响应面优化法得到了较佳的叶轮结构参数为：叶片安装角23.34°、叶轮无量纲面积0.43和叶片夹角14.56°。在不同风机转速（1050、1350、1650r/min）、不同甘蔗长势（良好、较差和严重倒伏）和不同行驶速度（1、2、3km/h）下进行田间试验。结果表明：对于长势良好的甘蔗，当风机转速为1050r/min时，不同行驶速度下，优化后风机含杂率分别降低1.06、1.99、3.28个百分点；当风机转速为1350r/min时，优化后风机含杂率最多可降低2.5个百分点；当风机转速提升至1650r/min时，优化前后风机在各行驶速度下含杂率未表现出明显差异；对于长势较差和严重倒伏的甘蔗，优化后风机含杂率最多可分别降低5.45、2.1个百分点。优化后风机提升了甘蔗收获机在复杂田间环境中的排杂能力，且所得数据为后续风机研究提供了理论支持。

Abstract:

The extractor is one of the core components of the sugarcane chopper harvester, and its performance plays a vital role in the impurity rate of the sugarcane harvester, while the impeller is the core component of the extractor, and its aerodynamic characteristics is closely related to the effect of the exhaust. Aiming at the problem of insufficient optimization of the performance of the impeller of the miscellaneous fan of the sugarcane harvester, which affects the miscellaneous effect, taking the impeller of the miscellaneous fan of the transverse sugarcane harvester as the object, and the influences of the type of hub, mounting angle of the impeller β, number of the impeller Nb, dimensionless area of the impeller G, angle of the impeller γ on the aerodynamic characteristics of the fan and its mechanism were researched. With the objective of increasing the full pressure of the fan, the best impeller structure parameters were obtained by the response surface optimization method, which were the blade mounting angle of 23.34°, the impeller dimensionless area of 0.43 and the blade angle of 14.56°. Field experiments were conducted at different fan speeds (1050r/min, 1350r/min and 1650r/min), different cane growth conditions (good, poor and severe collapse) and different traveling speeds (1km/h, 2km/h and 3km/h). The results showed that for sugarcane with good growth, the optimized turbines reduced the impurity rate by 1.06, 1.99 and 3.28 percentage points at different driving speeds when the turbine rotational speed was 1050r/min;when the turbine rotational speed was 1350r/min, the optimized turbines reduced the impurity rate by 2.5 percentage points at most;when the turbine rotational speed was increased to 1650r/min, the optimized fan did not show obvious differences in the impurity rate at each driving speed;for the sugarcane with poor growth and serious collapse, the optimized fan could reduce the impurity rate by up to 5.45 and 2.1 percentage points, respectively. The optimized fan improved the ability of the sugarcane harvester to remove impurities in complex field environments, and the obtained data can provide theoretical support for subsequent fan research.