Experiments were conducted in an indoor soil bin filled with sandy clay loam soil. Tests were carried out with tillage tines to study the effect tool width on soil disturbance and draught. Depth of operation was held ...Experiments were conducted in an indoor soil bin filled with sandy clay loam soil. Tests were carried out with tillage tines to study the effect tool width on soil disturbance and draught. Depth of operation was held constant at 35 mm and then at 70 mm while speed was varied at three levels of 1.0, 3.6 and 9.0 km/h. The widths of the tines tested were 10, 20, 31, 40, 51, 88, 126, 163 and 200 mm. The cone penetration resistance of the soil varied from 400 to 600 kPa. Draught was measured with a load cell while soil disturbance was measured with a profile meter and meter rule. Draught increased at a decreasing rate with tine width. Quadratic models best fitted the data points with high R2 values. The increase in draught was affected by the forward speed since higher draught values were obtained at higher speed. Results show that the parameters of soil disturbance increased with increase in tine width, except height of ridge （hr）, which did not show any specific trend. The specific draught was highest （10.63 N/cm） with tine T20 while Tine T1 had the least specific draught of 5.2 N/cm.展开更多
为获取正弦指数曲线型开沟刀片的最佳结构参数,依据正弦指数曲线方程和二次正交旋转中心组合设计方案,设计了15种型式的开沟刀片,并进行土槽试验。以弯折角、弯曲半径、切土角为影响因子,以功率消耗和沟深稳定性系数为响应值,利用Design...为获取正弦指数曲线型开沟刀片的最佳结构参数,依据正弦指数曲线方程和二次正交旋转中心组合设计方案,设计了15种型式的开沟刀片,并进行土槽试验。以弯折角、弯曲半径、切土角为影响因子,以功率消耗和沟深稳定性系数为响应值,利用Design-Expert 8.0.6软件进行回归分析和响应面分析,探求单因子及交互因子对响应值的影响效应,并结合非线性优化计算方法,对正弦指数曲线型开沟刀片的结构参数进行优化计算。结果表明:在土壤坚实度为0.29 MPa、土壤含水率16.2%的条件下,各因子对功率消耗的影响贡献由大到小为:弯折角、切土角、弯曲半径;对沟深稳定性系数的影响贡献由大到小为:切土角、弯折角、弯曲半径。优化所得正弦指数曲线型开沟刀片最佳结构参数:弯折角为86.75°,弯曲半径为12 mm,切土角为13.8°,此时功率消耗理论最小值为32.32 k W,沟深稳定性系数为95.6%,验证试验表明功率消耗最小值为34.27 k W,沟深稳定性系数为92.82%,理论值与试验值误差小于10%,验证了回归模型的正确性。将优化前、后和现有开沟刀片在2种不同土壤条件下进行对比试验,结果表明优化后刀片的功率消耗比优化前分别下降4.28 k W和4.23 k W,沟深稳定性系数分别提高7.12个百分点和7.02个百分点,比现有开沟刀片下降7.68 k W和6.91 k W,沟深稳定性系数提高14.34个百分点和8.34个百分点。研究成果为正弦指数曲线型开沟刀片的优化设计提供了理论参考。展开更多
文摘Experiments were conducted in an indoor soil bin filled with sandy clay loam soil. Tests were carried out with tillage tines to study the effect tool width on soil disturbance and draught. Depth of operation was held constant at 35 mm and then at 70 mm while speed was varied at three levels of 1.0, 3.6 and 9.0 km/h. The widths of the tines tested were 10, 20, 31, 40, 51, 88, 126, 163 and 200 mm. The cone penetration resistance of the soil varied from 400 to 600 kPa. Draught was measured with a load cell while soil disturbance was measured with a profile meter and meter rule. Draught increased at a decreasing rate with tine width. Quadratic models best fitted the data points with high R2 values. The increase in draught was affected by the forward speed since higher draught values were obtained at higher speed. Results show that the parameters of soil disturbance increased with increase in tine width, except height of ridge （hr）, which did not show any specific trend. The specific draught was highest （10.63 N/cm） with tine T20 while Tine T1 had the least specific draught of 5.2 N/cm.
文摘为获取正弦指数曲线型开沟刀片的最佳结构参数,依据正弦指数曲线方程和二次正交旋转中心组合设计方案,设计了15种型式的开沟刀片,并进行土槽试验。以弯折角、弯曲半径、切土角为影响因子,以功率消耗和沟深稳定性系数为响应值,利用Design-Expert 8.0.6软件进行回归分析和响应面分析,探求单因子及交互因子对响应值的影响效应,并结合非线性优化计算方法,对正弦指数曲线型开沟刀片的结构参数进行优化计算。结果表明:在土壤坚实度为0.29 MPa、土壤含水率16.2%的条件下,各因子对功率消耗的影响贡献由大到小为:弯折角、切土角、弯曲半径;对沟深稳定性系数的影响贡献由大到小为:切土角、弯折角、弯曲半径。优化所得正弦指数曲线型开沟刀片最佳结构参数:弯折角为86.75°,弯曲半径为12 mm,切土角为13.8°,此时功率消耗理论最小值为32.32 k W,沟深稳定性系数为95.6%,验证试验表明功率消耗最小值为34.27 k W,沟深稳定性系数为92.82%,理论值与试验值误差小于10%,验证了回归模型的正确性。将优化前、后和现有开沟刀片在2种不同土壤条件下进行对比试验,结果表明优化后刀片的功率消耗比优化前分别下降4.28 k W和4.23 k W,沟深稳定性系数分别提高7.12个百分点和7.02个百分点,比现有开沟刀片下降7.68 k W和6.91 k W,沟深稳定性系数提高14.34个百分点和8.34个百分点。研究成果为正弦指数曲线型开沟刀片的优化设计提供了理论参考。
