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1.
根据破壳油菜籽的物料特性,设计了一种气流上吸与振动筛相结合的破壳油菜籽分选机,对分选原理和主要结构参数进行了分析,研究了喂入量和前、后风道风速对分选效果的影响。试验结果表明,喂入量对壳中含仁率的影响存在最佳值点;前风道风速对壳中含仁率和仁中含壳率的影响比后风道风速更大;喂入量为750kg/h和前、后风道风速分别为1.5m/s、5.3m/s条件下,分选机损失率较低。  相似文献   

2.
核桃壳仁风选机的设计与试验研究   总被引:1,自引:0,他引:1  
为实现核桃加工破壳后的壳仁分离,采用风选式原理对核桃壳仁进行分离。以喂入量、风量级、风腔长度和管道倾角为试验因素,进行混合水平正交试验。试验结果表明:风量大小和风腔长度对壳中含仁率有显著影响,风腔长度对仁中含壳率有极显著的影响,喂入量对高路仁损失率有极显著的影响。通过优化试验方案得出壳仁风选机的最优参数:喂入量为0.16kg/s、风量级为2.5级、风选腔长度3.2m和管道倾角θ取60°,能够达到仁中含壳率小于3%,壳中含仁率小于7%,高路仁损失率小于5%,均符合设计指标要求。  相似文献   

3.
山核桃物料风选机理与风选性能试验研究   总被引:1,自引:0,他引:1  
破壳后物料分离是山核桃深加工的关键技术,仿真分析了山核桃破壳后各种形状壳仁的物理特性。研究利用物料的壳与仁的含水率的区分度、物料的力学参数与其形状系数使壳、仁和壳仁嵌合物的悬浮速度重合区间减小,并且研究了风速均匀性和控制风速精度对复杂物料风选的影响。混合物料试验确定了在风速8. 2 m/s、仁含水率为23. 6%、壳含水率为5%、迎风面容量比为50%左右时,总体清选率为99. 2%、误选率为0. 8%,剩余物料在含水率均为23. 6%、风速为11. 7 m/s时使清选率达到100%、误选率2. 3%,含水率为23. 6%时物料最大碰撞力为0. 003 1 N。  相似文献   

4.
油菜联合收获后含杂油菜籽复清机设计与试验   总被引:2,自引:0,他引:2  
廖庆喜  王昌  何坤  袁佳诚  万星宇 《农业机械学报》2021,52(10):175-185,232
针对现有油菜联合收获机收获作业时油菜籽粒细小不易分离导致收获后籽粒含杂率高、人工复清劳动强度大、缺乏晾晒前机械化复清装备的生产实际问题,设计了一种适于油菜联合收获机作业后含杂油菜籽的复清机。通过运动学和动力学分析确定了螺旋输送装置、离心振动式筛分装置和侧向风选装置的结构及其运行参数,解析了离心振动式筛分装置离心过程和振动过程,基于CFD分析了清选罩壳内部气流场状态。以振动频率、垂直振幅和离心风机出风口风速为影响因素,以油菜联合收获后含杂油菜籽复清机籽粒含杂率和筛分效率为评价指标,开展了单因素试验与正交试验,确定了较优运行参数组合。单因素试验结果表明:振动频率在12.08~14.61Hz,垂直振幅在3.59~3.64mm,离心风机出风口风速在5~7m/s范围内时,清选性能较优;正交试验结果表明:影响含杂率因素主次为离心风机出风口风速、振动频率、垂直振幅,影响筛分效率因素主次为振动频率、垂直振幅、离心风机出风口风速,确定较优参数组合:振动频率为14.61Hz、垂直振幅为3.61mm、离心风机出风口风速为7m/s,在此参数组合下,油菜联合收获后含杂油菜籽复清机的籽粒含杂率平均值为0.53%,筛分效率平均值为98.39%,符合油菜籽粒后续存储标准(含杂率小于3%)。  相似文献   

5.
短风道核桃壳仁分选机研制   总被引:1,自引:0,他引:1  
目前国内核桃破壳取仁主要依靠手工,效率低,成本高,制约了核桃产业的发展。介绍了项目组新研制的小型短风道核桃壳仁分选机的结构、工艺、工作原理、特点及试验情况,该设备集核桃破壳、壳仁分级和壳仁分离于一体,可以同时完成核桃破壳、壳仁分级与风选分离,为实现核桃壳仁机械化分离加工创造了条件。   相似文献   

6.
栅栏式核桃二次破壳机的设计与试验   总被引:1,自引:1,他引:0  
设计核桃二次破壳机用于核桃加工生产线中弥补一次破壳带来的不足。栅栏式核桃二次破壳机应用挤压揉搓原理,通过内滚筒与栅栏间的间隙实现二次破壳。对该机关键部分进行设计,再通过正交试验确定其最优参数。栅栏式核桃二次破壳机能适应不同大小和不同开口程度的核桃,在破壳过程中,内滚筒转速和栅栏与内滚筒间的间隙是影响脱仁率和破壳率的主要因素。通过试验研究得到,在滚筒转速70 r/min,滚筒长度80 cm,喂入量3 kg/min时,有较高的核桃脱仁率和核桃高露仁率,能运用于核桃破壳取仁生产线中,为核桃壳仁分离提供保障。  相似文献   

7.
韩豹  吴文福  黄新国 《农业工程》2010,(12):125-130
为进一步改善寒地超级稻霜前收获摘脱台的性能,降低梳脱损失,通过对影响摘脱台工作性能的主要参数和结构特点的分析,在4ZTL-1800型气吸式割前摘脱稻麦联合收割机研究基础上,设计了一种具有可更换3种滚筒的摘脱台。以摘脱台的总损失为评价指标,对摘脱滚筒线速度、喂入速度、喂入口开度与喂入口风速进行了单因素和多因素正交试验。单因素试验表明:摘脱滚筒线速度、喂入速度和喂入口风速三因素对摘脱损失有显著影响。正交试验表明:最佳组合为滚筒线速度23 m/s,喂入速度1.1 m/s,喂入口开度120 mm,喂入口气流速度14 m/s,此技术条件下摘脱损失不大于1%。所设计的摘脱台满足超级稻收获要求,并为超级稻割前摘脱联合收割机摘脱台的设计提供依据。  相似文献   

8.
双出风口多风道离心风机清选装置主要参数试验优化   总被引:1,自引:0,他引:1  
针对小麦联合收获机双出风口多风道离心风机主要作业参数调节不当导致清选损失与含杂较高这一问题,对双出风口多风道离心风机主要相关因素进行小麦台架试验,寻找各因素对收获质量的影响规律,并以清选损失率、含杂率作为评价指标,寻找最优参数组合。选择对小麦台架试验影响较大的3个试验因素,即喂入量、风门开度及风机转速,利用Design-Expert的中心组合试验设计理论,对3因素3水平进行响应面试验并对结果进行分析,研究各主要因素对损失、含杂2个指标规律的影响,并建立数学模型。台架试验表明:对损失较显著的影响因素有风机转速、风门开度;对含杂较显著的因素有风机转速、风门开度。通过对3个因素进行目标参数优化得到最优组合参数:喂入量4.68kg/s、风门开度10°,风机转速1600r/min。利用最佳组合参数进行台架试验验证,结果表明:损失率和含杂率分别为0.71%与0.43%,满足国标损失率≤1.2%、含杂率≤2.0%的要求,可为多风道离心风机的研究与设计提供数据参考与技术支撑。  相似文献   

9.
柔性带差速挤压核桃脱壳性能试验   总被引:3,自引:0,他引:3  
设计了核桃破壳取仁分离装置,但存在破壳不完全、碎壳未脱落的现象。为此利用装置中的柔性带差速挤压脱壳系统对核桃进一步脱壳取仁并对其效果进行分析。采用单因素试验方法分别探究上下带间距A、上下带速度差B及上工作带张紧力C对核桃脱壳效果的影响,进而设计正交试验,分析试验因素对脱壳取仁效果的影响。试验结果表明:对于一露仁率和二露仁率,影响顺序为C、A、B;对于碎仁率和未露仁率,影响顺序为A、C、B。在上下带间距为14 mm、上下带速度差为0.19 m/s、上工作带张紧力为231 N的参数下脱壳效果最为理想,一露仁率、二露仁率、碎仁率、未露仁率分别为77%、16.7%、4.3%、2%,即脱壳率为98%,整仁率为93.7%。  相似文献   

10.
坚果破壳后需要获取干净的果仁,依靠人工效率低、成本高,依靠普通筛分法,由于部分坚果破壳后壳仁尺寸比较接近,筛分效果并不理想,本文介绍了项目组研制的一种风筛式坚果壳仁分选机的结构、工作原理、机构及设备特点与试验情况,旨在为坚果破壳后壳仁分选提供一种结构简单,易操作的技术设备。  相似文献   

11.
Overland water and salt flows in a set of rice paddies   总被引:1,自引:0,他引:1  
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   

12.
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   

13.
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   

14.
对《种子法》存在问题的探讨   总被引:1,自引:0,他引:1  
《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   

15.
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   

16.
赵异 《湖南农机》2007,(3):31-32
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   

17.
A European irrigation map for spatially distributed agricultural modelling   总被引:1,自引:0,他引:1  
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   

18.
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   

19.
农村信息化服务的现状及建设措施   总被引:2,自引:0,他引:2  
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。  相似文献   

20.
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   

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