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基于响应面分析法的香蕉茎秆纤维刮杂装置优化设计 总被引：1，自引：0，他引：1
为了优化香蕉茎秆纤维提取机刮杂装置部件结构,提高纤维提取质量,以刮杂装置的刀辊速度、刀片间距、定刀弧长为影响因子,采用响应面优化设计方法,建立了影响因子与纤维提取率之间的数学模型,确定了较优的参数组合。试验表明:当香蕉纤维提取机刮杂装置影响因子的实际参数为刀辊转速1 200r/min、刀片间距1 1 0 mm、定刀弧长5 0 mm时,纤维提取率平均可达到9 2.6%,符合优化目标及生产要求。研究结果可为植物纤维提取装置的研发和应用提供理论依据和思路。 相似文献
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针对我国现有香蕉茎秆纵向切片分离设备切片效率低、人工劳动强度大等问题,提出一种香蕉茎秆往复切片方案,设计了往复切削式香蕉茎秆切片分离机。整机由机架、茎秆推动装置、茎秆固定下压装置、茎秆切片分离装置、传送带构成。基于香蕉茎秆物理特性,确定该机关键部件的结构参数,得到该机最优工作参数,利用响应面分析法研究电机转速、茎秆待切割部分厚度、支撑板与切割刀片间距3个因素与香蕉茎秆切片合格率的作用模型。分析结果表明,电机转速为40r/min、茎秆待切割部分厚度为17mm、支撑板与切割刀片间距为5mm时,香蕉茎秆切片合格率为98.45%。样机试验表明最优工作参数情况下香蕉茎秆切片合格率为97.78%,验证响应面分析的可行性。该研究对香蕉茎秆切片分离机的设计具有重要技术参考价值。 相似文献
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香蕉秸秆含水率高、脆性大、富含纤维素,而现有的香蕉秸秆粉碎还田机粉碎率低、能耗高且茎秆纤维易缠绕粉碎刀辊。针对上述问题,设计一种异向双辊式香蕉秸秆粉碎还田机,介绍该机的总体设计方案,确定粉碎装置、传动系统、限深装置的结构和主要参数。田间试验表明:该机器在田间作业时,当刀辊转速为1 600 r/min,前进速度为12.9 m/s,粉碎刀片长度为124 mm时可达到最优工作状态,此时平均工作效率为0.437 hm^2/h,高于性能指标0.400 hm^2/h;机器平均粉碎合格率为97.09%,大于行业标准94%,达到秸秆粉碎还田的农艺要求。 相似文献
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针对现有鲜食玉米收获机在收获果穗时,果穗中含有茎叶等杂质,影响运输、贮存和后续加工等问题,采用轴流风机负压除杂技术去除果穗中的茎秆和茎叶等杂质,同时在除杂装置内增加动、定刀,切碎杂质,便于后续的打包回收利用,并对风机负压除杂装置进行了性能分析和参数优化。通过对动、定刀进行动力学分析,对动、定刀数和刀间隙进行分析,确定了该装置的风机转速范围为1326~1573r/min,动、定刀间隙20mm,定刀数为3~8。采用二次回归正交组合试验方案,以风机转速、定刀数、喂入量为试验因素,以果穗含杂率和茎秆切碎长度合格率为试验指标进行台架试验,通过分析各因素对指标贡献率,得到影响茎秆切碎长度合格率的主次顺序为喂入量、风机转速、定刀数,影响果穗含杂率的主次顺序为风机转速、喂入量、定刀数。建立了参数优化数学模型,利用Optimization模块优化得出,当风机转速为1524r/min、单排定刀数为4、喂入量为7.6kg/s时,茎秆切碎长度合格率为96.8%,果穗含杂率为0.69%。对优化后的参数组合进行了5组验证试验,得到茎秆切碎长度合格率平均值为96.2%,果穗含杂率平均值为0.71%。相比于传统收获机,该装置使果穗含杂率降低了23.3%,说明该优化参数能够满足鲜食玉米果穗收获和茎叶青贮相关技术要求。 相似文献
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大白菜种子清选装置主要由茎秆分离装置和横流风机吸杂装置两部分组成。前者根据大白菜种子脱出物的几何特性差异,利用内流式圆筒筛分离出短茎秆和果荚壳;后者根据脱出物的空气动力学特性差异,利用横流风机吸走大白菜种子脱出物中的轻杂物,具有低损失、低含杂率等特点。为此,基于上述结构和原理设计了一种室内清选试验台,以含杂率和损失率作为试验指标进行了正交试验、回归试验,并优化得出了最佳运行参数组合。研究结果表明:当搅龙转速160r/min、圆筒筛转速50r/min、搅龙与圆筒筛间隙10mm、横流风机转速700r/min、下落物料角度30°、风道高度500mm时,清选装置的含杂率为1.71%,损失率为0.64%。 相似文献
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为进一步提升胡麻脱粒物料分离清选作业机的工作性能,采用数值模拟仿真试验方法分析确定获得的单因素参数,以喂料装置振幅、物料层调节厚度和吸杂风机转速为自变量,以籽粒含杂率和清选损失率为响应值,依照Box-Behnken试验设计原理,采用三因素三水平响应面分析方法,分别建立了各因素与籽粒含杂率和清选损失率之间的数学模型,并对各因素及其交互作用进行分析。结果表明:3个因素对籽粒含杂率影响的主次顺序为吸杂风机转速、喂料装置振幅和物料层调节厚度,对清选损失率影响的主次顺序为吸杂风机转速、物料层调节厚度和喂料装置振幅;作业机最佳工作参数为:喂料装置振幅16.5 mm、物料层调节厚度7.0 mm、吸杂风机转速1 775 r/min(即对应的吸杂风机转速变频频率为59.2 Hz)。验证试验表明,籽粒含杂率和清选损失率均值分别为7.86%和1.58%,说明在最优工作参数下作业机能够降低胡麻脱粒物料在机械化分离清选过程中的含杂与损失程度。 相似文献
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针对我国香蕉秸秆粉碎还田作业过程中香蕉秸秆粉碎质量差,秸秆缠绕堵塞等问题,设计了一种双定刀滑切防缠式香蕉秸秆粉碎还田机。基于滑切定理,解析了粉碎刀随轴转动过程中的动态滑切角和粉碎定刀滑切角的相对作用原理,以等速螺线设计L形粉碎定刀刀刃曲线,确定了粉碎刀结构参数;对香蕉秸秆缠绕粉碎刀辊进行受力分析,设计防缠绕板并确定装配数量与结构参数;以装置前进速度、粉碎刀辊转速、防缠绕板高度为试验因素,以香蕉秸秆粉碎合格率、抛撒不均匀度和香蕉秸秆缠绕数量为评价指标进行三因素三水平正交试验,建立因素与指标的响应面数学模型。试验结果表明,最优参数组合为作业机前进速度1.5 m/s、防缠绕板高度41.6 mm、粉碎刀辊转速1 800 r/min,此时香蕉秸秆粉碎合格率为93.8%,香蕉秸秆缠绕数量为26,香蕉秸秆抛撒不均匀度为12.1%。以最优组合进行田间试验验证,试验结果表明双定刀滑切防缠式香蕉秸秆粉碎还田机整机防缠性能优越,满足设计要求。 相似文献
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Overland water and salt flows in a set of rice paddies 总被引：1，自引：0，他引：1
E. Playn O. Prez-Coveta A. Martínez-Cob J. Herrero P. García-Navarro B. Latorre P. Brufau J. Garcs 《Agricultural Water Management》2008,95(6):645-658
Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m−1) and an infiltration rate of 5.8 mm day−1. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day−1), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day−1 was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration. 相似文献
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瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。 相似文献
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对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。 相似文献
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对《种子法》存在问题的探讨 总被引：1，自引：0，他引：1
李鹏 《农业机械化与电气化》2011,(6):129-130
《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。 相似文献
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About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered. 相似文献
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在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。 相似文献
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Gunter Wriedt Marijn van der Velde Alberto Aloe Fayçal Bouraoui 《Agricultural Water Management》2009,96(5):771-789
We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications. 相似文献
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在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。 相似文献
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车辆ABS控制算法的研究及探讨 总被引：1，自引：0，他引：1
对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。 相似文献