秸秆打捆机结构改进及仿真分析

我国甘蔗叶秸秆资源极其丰富,是一种宝贵的生物资源。甘蔗叶秸秆变废为宝,化害为利处理,已成为社会亟待解决的问题。实现甘蔗叶秸秆资源化利用,关键在于解决甘蔗叶秸秆如何高效回收。目前使用的秸秆打捆机会出现喂入口堵塞、卷捆不畅等问题。为此,通过虚拟样机技术对目前使用的秸秆打捆机进行结构改进和仿真分析实验,应用SolidWorks软件建立改进前和改进后打捆机的三维实体模型,再应用ANSYS和ADAMS软件对打捆机整机进行仿真分析。通过对改进前和改进后两款打捆机进行力学分析和仿真实验,结果表明:打捆机喂入机构增加喂入对辊和碾压对辊,可大幅提升打捆机的喂入能力;卷捆室钢辊优化排列和钢辊表面结构优化可大幅提升卷捆室的卷捆能力,一定程度上解决打捆机喂入口堵塞、打捆不畅等问题,为秸秆打捆机后续创新设计提供理论支持。     

小型秸秆圆捆机喂入机构的设计与试验

针对传统小型秸秆圆捆机打捆作业时经常会出现堵塞的问题,结合打捆要求,设计一种由前置喂入对辊、后置挤压对辊和护板组成的新型喂入机构,并以稻秆为试验原料,采用3因素5水平正交旋转设计方法进行试验研究,分析前置喂入对辊的间距、后置挤压对辊的间距以及挤压倾角对秸秆喂入性能的影响,试验表明当前置喂入对辊的间距为50 mm、后置挤压对辊的间距为22 mm、挤压倾角为19°时,喂入机构可有效减少小型秸秆圆捆机出现堵塞的问题,满足日常打捆需求。该研究可为圆捆机的结构设计提供参考。     

钢辊式圆捆机旋转草芯形成影响因素分析与优化

针对国产的中小型钢辊式圆捆机收获完整稻秆易产生堵塞的问题,利用自行设计的钢辊式圆捆机(草捆直径约500 mm)试验装置对其打捆过程进行了研究。通过高速摄像分析可知:旋转草芯形成过程实质上是稻秆在卷压室内连续卷绕累积的过程,形成的旋转草芯可对后续喂入的稻秆产生较大的牵带作用,进而消除打捆堵塞。通过试验分析可知,旋转草芯形成过程主要依靠钢辊对稻秆的摩擦牵引及后续喂入稻秆的持续推动完成的,据此,针对影响钢辊式圆捆机形成旋转草芯的主要因素——钢辊对稻秆的摩擦作用、捡拾器弹齿端点线速度以及稻秆喂入量为试验因素,以旋转草芯形成时的干物质质量为评价指标,进行了试验研究。结果表明:各因素对旋转草芯形成时的干物质质量贡献率从大到小依次为:钢辊对稻秆的摩擦作用、捡拾器弹齿端点线速度、稻秆喂入量。当因素参数组合为钢辊与稻秆间的滑动摩擦因数约0.65、捡拾器弹齿端点线速度2.23 m/s、稻秆喂入量1.5 kg/s时,旋转草芯形成时的干物质质量为1.58 kg。研究结果可为钢辊式圆捆机的设计及其作业参数优化提供理论及技术依据。     

可变压捆室打捆机结构设计与仿真分析

针对传统秸秆打捆机收获农作物秸秆时形成圆草捆直径单一的问题,设计一种由捡拾机构、喂入机构、压捆机构和草捆卸载装置等组成的可变压捆室圆捆机。在Solidworks中建立可变压捆室圆捆机三维模型,简述其工作原理和关键部件的结构设计,并对整机动力传动系统进行分析;分析草芯在压捆室内累积过程,得出物料在压捆室内运动的规律,并通过计算得出钢辊线速度为2.29 m/s;运用ADAMS软件对打捆机进行运动学仿真,验证打捆机作业时不会发生物料堵塞和堆积现象,得到钢辊线速度为2.3 m/s,与计算结果基本一致;利用ANSYS Workbench软件对打捆机机架进行模态分析,得出打捆机正常作业时机架不会发生共振现象。为后续秸秆打捆机的创新设计和结构改进提供理论支持。     

钢辊外卷式圆捆打捆机设计与试验

设计了由传动系统、牵引装置、捡拾器、喂入机构、成捆室、捆绳机构、液压系统以及卸草器等组成的钢辊外卷式圆捆打捆机,简述了圆捆打捆机的工作原理以及关键部件的结构设计等。对圆捆打捆机的运动参数进行了设计计算,对喂入机构的运动轨迹进行了描述,分析了螺线型成捆室的特点。为检验圆捆打捆机的可靠性和适应性,在不同的作业环境和条件下进行了性能试验和生产考核,结果证明该机结构能够适应各种不同的作业环境。     

9YGJ-2.2型捡拾圆草捆打捆机设计与试验

针对国内圆草捆打捆机普遍存在捡拾器凸轮盘磨损严重,故障率高、草捆密度不均、整机作业效率低及可靠性差等问题,以现有圆捆机为研究基础,设计了捡拾器、螺旋连续喂入机构、卷捆室等,研制了9YGJ-2.2型圆草捆打捆机,并进行了性能试验。试验结果表明,主要技术指标达到设计要求和国家标准的规定。     

辊盘式圆捆机卷捆机理分析与试验

针对国产中小型钢辊式圆捆机收获完整稻秆时易于堵塞问题,设计了侧圆盘与钢辊组合式(简称辊盘式)卷捆机构,并利用自制辊盘式圆捆机试验装置对其卷捆过程进行了试验研究。通过高速摄像与运动学分析可知:完整稻秆刚进入卷捆室后在钢辊及侧圆盘共同作用下沿钢辊做整周运动,稻秆在卷捆室内运转一周重新到达卷捆室底部位置时,两侧壁摩擦力会使其停止旋转,而在卷捆室底部产生持续累积过程,由侧圆盘对稻秆产生的摩擦带动力可缩短累积稻秆形成旋转草芯进程,进而避免堵塞现象发生。据此以影响辊盘式圆捆机形成旋转草芯的主要因素——圆盘直径、圆盘转速、长宽比(稻秆长度与卷捆室宽度的比值)为试验因素,将旋转草芯形成时的稻秆质量作为评价指标进行试验。试验表明各因素影响评价指标的主次顺序为圆盘直径、长宽比、圆盘转速;取圆盘直径380 mm、圆盘转速135 r/min,当长宽比为1.00时,旋转草芯形成时的稻秆质量为1.21 kg,当长宽比为1.26时,旋转草芯形成时的稻秆质量为3.44 kg,并且无堵塞现象发生。研究结果可为辊盘式圆捆机的设计及其作业参数优化提供理论及技术依据。     

圆草捆打捆机的设计及优化

设计了一款圆草捆打捆机,通过牵引机械输入动力,采用凸轮滑道型捡拾系统技术和成型室钢辊预压缩技术,实现了打捆、缠网、密度调节、报警等自动化控制,整机自动化水平高。通过试验对捡拾系统进行了优化,提高了整机性能,该圆捆机广泛应用于牧草、秸秆作物的打捆。     

青饲圆捆机对数螺线式成形装置设计与试验

为提高青贮饲料的打捆作业效率和作业质量,在现有青贮饲料打捆技术的基础上,设计了一种用于青贮作业,由喂料预压机构、对数螺线式二次压捆机构组成的对数螺线式圆草捆成捆装置。对不同含水率的玉米秸秆进行了不同压力角的试验,试验结果表明:取压力角小于20°的对数螺线式喂料压捆过程,解决了圆形内腔的成捆室在喂入粗大、湿润、坚硬物料时的堵塞问题;对含水率为50%~70%的玉米秸秆,装置压力角α值取15°时,喂入速度和压捆速度匹配较好;装置对高含水率的玉米秸秆具有较好的适应性。     

浅析一种圆捆机的工作原理

圆捆打捆机能够完成稻草、麦草、玉米秆、油菜秆、花生藤、豆秆等秸秆、牧草的捡拾打捆作业.介绍了一种圆捆打捆机的工作原理,阐述了圆捆打捆机捡拾器、喂入机构、打捆室、卸载机构等的设计原理,为进一步研究和开发秸秆打捆机具提供了参考.     

Overland water and salt flows in a set of rice paddies

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.     

瓦房店市水果生产标准化发展研究

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。     

金谷子耐旱TG118引种试种及推广应用

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。     

对《种子法》存在问题的探讨

《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。     

Review of the Egyptian experience in implementing land drainage projects

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.     

和谐社会理论建设的几点哲学思考

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。     

A European irrigation map for spatially distributed agricultural modelling

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.     

粉质仪和拉伸仪在面粉生产中的应用

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。     

农村信息化服务的现状及建设措施

分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。     

车辆ABS控制算法的研究及探讨

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。