糖用甜菜物理特性试验分析.pdf

第 28 卷增刊 2农 业 工 程 学 报Vol.28Supp.2 2012 年10 月Transactions of the Chinese Society of Agricultural EngineeringOct. 2012297 Experimental analysis on physical characteristics of sugar beet Wang Fangyan1,2, Zhang Dongxing1 (1. College of Engineering, China Agricultural University, Beijing 100083, China; 2. College of mechanical and electrical engineering, Qingdao Agricultural University, Qingdao 266109, China) Abstract: According to the measurements of the field conditions and physical parameters of cv KWS3148 sugar beet during harvesting stage, its planting mode has been established. SPSS was used to measure the main interval and frequency distribution of physical and geometric parameters for sugar beet, the relative position of sugar beet to soil has been determined, and the physical and geometric model of sugar beet was established. According to the test of the pulling force of sugar beet harvesting, the required pulling force of sugar beet under natural soil condition and the condition of the cut loosen soil on both sides by artificial have been achieved, which were (365 196) and (259 176) N, respectively. The pulling force was significantly correlated with the weight of root tuber and the size of the minor axis of the ellipse(P 0.01), which is the intersecting surface of the root tuber. And it has notable bi- factorial correlations with the weight of root tuber, the maximum cross- sectional dimension and the length of root tuber at the 0.01 level. The pulling force was correlated with soil conditions, and was slightly related with the root systems of sugar beet. The test results indicated that the height of a root tuber above the ground is (60 24.4)mm, the maximum width of a root tuber is (120 28) mm, the length of the root tuber was (202 45.3) mm, the weight of the root tuber was (1198 530) g and the wedge angle of a sugar beet was (15.3 2.14 ). The established geometric model of sugar beet could provide a reference for the design of topper and harvester of sugar beet. Key words: physical properties, crops, soil, sugar beet, pulling force, experimental analysis doi：10.3969/j.issn.1002-6819.2012.z2.052 CLC number: S225.91+2Document code: AArticle ID: 1002-6819(2012)-Supp.2-0297-07 Wang Fangyan, Zhang Dongxing. Experimental analysis on physical characteristics of sugar beetJ. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2012, 28(Supp.2): 297303. (in English with Chinese abstract) 王芳艳，张东兴. 糖用甜菜物理特性试验分析J. 农业工程学报，2012，28(增刊2)：297303. 0Introduction Sugar beet is a cash crop with high value. Its planting area accounts for about 48% of that of the sugar- yielding crops in the world and it ranks second after sugarcane1- 2. Sugar beet was introduced to china in 1906 and three relative concentrated planting areasincludingNortheast(Heilongjiang,Jilin, Liaoning), North China (Inner Mongolia, Shanxi, Hebei) and Northwest (Xinjiang, Gansu, Ningxia) have been formed. Among them, the planting area of Northeast accounts for about 65% of the total area of sugarbeet.TheplantingareaofHeilongjiang, Xinjiang and Inner Mongolia accounts for more than Received date：2012- 06- 21Revised date：2012- 09- 25 Foundation item ： Ministry of agriculture soil- machine- plant system technology key laboratory of machine Biography：Wang Fangyan (1979), female, Ph.D, major in agricultural machinery design and performance experiment research. Email: wfy_66163.com Corresponding author： Zhang Dongxing (1958), male, Ph.D., professor, major in agricultural mechanization engineering. Beijing College of Engineering, ChinaAgricultural University, 100083. Email: 90% of the total area3. With the saturation of sugarcane planting area in China, beet sugar as a main substitution for the future needs of sugar has large space of development. In recent years, with the development of the transplanting techniques and the popularization of fine varieties, beet transplanting mode has been gradually valued by farmers4- 5. The shortage of production equipments has become the bottleneck of sugar beet industry development6- 9. The physical properties of sugar beet are the basis of the design of sugar beet machinery and equipment. The research on physical properties of sugar beet also helps to guarantee machinery quality and their performance. At present, there have been few researches on physical properties of sugar beet at home and abroad. The researchers mainly concentrated on cell injury and mechanical properties of the root tuber, which are insufficient for providing systematic theoretical evidence for the research of machinery and equipment for seedling killing, harvesting and processing of sugar beet10- 15. Therefore, analyzing the geometric parameters and properties of transplanting sugar beet could lay the 农业工程学报2012 年 298 foundation of the research to the methods of topping, harvesting and production equipment. 1Equipments and conditions 1.1Equipments TJSD- 750 soil compaction meter(Hangzhou Topology Instrument Company Limited), root force measuringinstrument(Engineeringcollege,China AgriculturalUniversity),DHG- 9123Aelectric thermostaticdryingoven(ShanghaiJingHong laboratoryequipmentlimitedcompany),YB electronicbalance(ShanghaiHaikangelectronic instrument factory), vernier caliper, band tape, the soil cutting ring, etc. 1.2Test conditions In the double row transplanting experimental field of sugar beet, which is in Xiaoertai town, Zhangbei County, Hebei Province, according to the “ General requirements for the measuring methods for testingconditionsofagriculturalmachinery“ (GB/T5262- 2008), the row spacing, the plant spacing, the width of the ridge bottom, the row spacing between the articulation (row spacing between two adjacent transplanting trip), height of ridge and natural growth condition of cv KWS3148 sugar beet have been measured to establish the planting mode. Planting mode and measured parameters are shown in figure 1. According to “ Sugar beet” (GB/T10496- 2002) and “ General requirements for the measuring methods for testing conditions of agricultural machinery” (GB/T5262- 2008), physical parameters of the leaf and the root tuber of sugar beet as index, geometry characteristicvaluesofthesamplehavebeen individually measured. Position of maximum cross section and surface cross section of sugar beet are marked as I and II, cross sections made by transverse cutting are individually marked as 1, 2, 3, and 4. After transversely cutting the beet sample with 5 equal parts, geometric parameters of cross sectional ellipse were measured, then the eccentricity of the ellipse could be achieved, and finally the geometric model of sugar beet were established. Using the SPSS statistical software to analyze and predict the interval and law of thephysicalparameters.Thestudyprovidesa reference for the following research and development of harvesting machinery. The position of cutting section is shown in figure 1. 1.2.1Measurementofgeometricparametersofsugarbeet According to “ Sugar beet” （GB/T10496- 2002） and “ General requirements for the measuring methods for testing conditions of agricultural machinery” (GB/T5262- 2008), physical parameters of the leaf and the root tuber of sugar beet as index, the geometry characteristicvaluewereindividuallymeasured. Position of maximum cross section and surface cross section of sugar beet are marked as I and II, cross sections made by transverse cutting are individually marked as 1, 2, 3, and 4. After transversely cutting the beet sample with 5 equal parts, geometric parameters of cross sectional ellipse were measured, then the eccentricity of the ellipse was achieved. Using the statistical software SPSS to analyze and predict the interval and law of the physical parameters. The results provide a basis for the following research and development of harvest machinery. The position of cutting section is shown in Figure 1. Note: a. semi- major axis of ellipse of the intersecting surface, b. semi- minor axis of ellipse of the intersecting surface, c. width of ridge bottom, d. row spacing, e. row spacing between the articulation, f. distance from maximum intersecting surface to top cutting, g. height of the beet that is exposed, h. height of ridge, m. scarified distance, n. scarified depth,. position of the maximum cross section,. position of surface cross section Fig.1Planting mode and measured parameters of sugar beet 1.2.2Pulling force test of sugar beet ThetestfieldlocatedinXiaoertaitown, Zhangbei County, Hebei Province. According to “ measurement for soil moisture”(NY/T52- 1987), the TJSD- 750 soil compaction meter was used to measure the moisture content and compaction of soil. Based on the principle of disc type harvest of sugar beet, the sugar beet were parallelly cut in soil of both sides of the plant, which was 50 mm outside of the edge of sugar beet, and the cutting depth is 120 mm. The method of soil cutting is shown in figure 1. The required pulling force for pulling the sugar beet out of soil,weremeasuredbyrootforcemeasuring instrument. The number of tail root was calculated, and the diameter and length of the dock root were measured. The statistical software SPSS has been used to analyze the correlation between pulling force and the weight of sugar beet, physical dimension of cross section, length of sugar beet, condition of the root of the tail and soil condition to provide theoretical basis for the design of harvesting equipment of sugar beet. 2Results and analysis 2.1Planting mode The growth and field conditions of sugar beet are 增刊 2王方艳等：糖用甜菜物理特性试验分析 299 shown in table 1. The row spacing of transplanting, the height of ridge and width of ridge bottom are stable, the row spacing between the articulations, the growing height were slightly difference, and the plant spacing were obviously different. The fluctuation was correlated with the technologies and habits of the driver during the transplanting process. Height of ridge and width of bottomoftheridgearebasicallydeterminedby cultivation hilling and weed control process. The row spacing of sugar beet is (600 23.2) mm, the plant spacing is (409 109.4) mm, the width of ridge bottom is (318 109.4)mm,therowspacingbetweenthe articulations is (643 102 joint spacing) mm, the height of ridge is (102 9.6) mm, the natural height of sugar beet is (378 66.8) mm and the actual height is (657 114.2) mm. Table 1 Growth and field condition of sugar beet Statistical indicators Row spacing/mm Plant spacing /mm Width of ridge bottom /mm Row spacing between the articulations/mm Height of ridge/mm Natural height of sugar beet/mm Actual height of sugar beet/mm Maximum value610500350700110450760 Minimum value57034029055095330570 Average value600409318643102378657 Standard deviation13.154.718.1514.833.457.1 Coefficient of variation 0.020.130.050.080.040.080.08 2.2Characteristics of the geometric parameters of sugar beet The shape of sugar beet could be approximately regarded as conical or wedged in harvest period. Randomly select eight sugar beet, the cross section could be approximately regarded as ellipsoid. The eccentricities of the elliptical cross sections are shown in table 2. From the table 2, the eccentricities of the elliptical cross sections of the same beet in different positions are stable with an average of 0.66, which is consistent with the structure of vascular bundles inside a sugar beet. Thus, a model with geometric parameters could be established, which is shown in Figure 2. Table 2Eccentricity of different cross section Eccentricity of sample Cross section 12345678 10.610.630.630.690.680.630.690.60 20.600.690.690.690.660.640.690.60 30.610.740.680.660.690.640.660.61 40.660.750.660.690.690.570.750.64 Average value0.620.700.660.680.680.620.690.61 Standard deviation 0.030.060.020.010.010.030.040.02 Coefficient of variation 0.040.080.030.020.020.050.050.03 Formula of volume and surface areas of sugar beet are 0 L ii Vabdl （1） 0 (24() L iii Sbabdl （2） Where,Vis the volume,Sis the surface area of sugar beet. For the convenience of calculating, the shape of root tuber and bottom surface of sugar beet could respectively and approximately be regarded as wedge and rectangle. The length and width of the rectangle are respectively the semi- major and the semi- minor axis of ellipse of the maximum intersecting surface of the sugar beet. Thus, the volume and surface area of a sugar beet can be approximately calculated as follow: VabL（3） 22 4SbLa bL（4） Where,Vis the volume,Sis the surface area of sugar beet. Note: aiis the semi- major axis of ellipse of the ith intersecting surface (i=1,2,3 .), biis the semi- minor axis of ellipse of the ith intersecting surface (i=1,2,3 .), a is the length of rectangle, b is the width of rectangle, L is the length of sugar beet, is the wedge angle of wedge body. Fig.2Geometrical model The growth condition of sugar beet is shown in table 3. Through the statistics, the yield of leaves of sugar beet is about 31 020 kg/hm2, and that of root tuber is about 71 880 kg/hm2. The size of the cross- sectional ellipse of root tuber, which is at the surface layer of the soils has little difference from that at the position where the section is the biggest, which can be considered as the position of the maximum cross section. The results could provide a reference to the height of seedling killing and the size of digging. 农业工程学报2012 年 300 Table 3Growth parameters of sugar beet Ellipse at position ofEllipse at position of Statistical indicators Leaf weight of a plant /g Leaf number of a plant / piece Length of major axis /mm Length of minor axis /mm Distance to top cutting /mm Length of major axis /mm Length of minor axis/mm Distance to top cutting /mm Length of tuber/mm Weight of tuber/g Maximum value75123150120100140118902551900 Minimum value32010906535906538160750 Average value51716120976111595602001198 Standard deviation99.22.91410.7212.222.65265 Coefficient of variation 10.22 By the statistical software SPSS, the histogram and normal curve of the frequency distribution of 5 evaluating indicator, which are the lengths of root tuber under the soil and above the soil, the major axis of the maximum cross- sectional ellipse, the length of root tuber, and the weight of root tuber, has been achieved and shown in figure 3 to figure 7. As shown in figure 3, the length of root tuber under the soil and above the soil are respectively 120,170 mm and less than 170 mm, respectively, accounting for 92% and 98% of the total samples. As shown in figure 4, the height of the root above the soil is 40, 70 mm, which accounts for 94% of the samples. Therefore, while cutting the top of sugar beet, the distance from the ground should be more than 40 mm. As shown in the figure 5 and 6, the major axis length of maximum cross section of root tuber is 90，140 mm, which accounts for 92% of the samples, and almost all the major axis length of maximum cross section and length of root tuber are respectively over 90 and 160 mm. These are of guiding significance to the design of the digging and the conveying appliance on a harvester. As shown in figure 7, the weight of root tuber is 800, 1600 g, which accounts for 92% of the samples. By statistical analysis on the parameters of the maximum cross- section, the ratio of the length of the minor axis to the major axis of the cross- sectional ellipse of root tuber, the average, the coefficient of variation and the standard deviation could be achieved, which are respectively 0.66, 0.92, 0.79, 0.034 and 0.044. The ratio of 96% of the sample is 0.73, 0.85. The maximum wedge angle of sugar beet is 27.5 , 41.5 , and the average is 33.3 . 2.3Pulling force of sugar beets and the correlation of parameters During the harvest period, the joint of beet leaf and root tuber is brittle and the tensile strength is limited, so it is difficult to directly pull the sugar beet out.Themoisturecontentofthesoil,the volume- weight and the average soil hardness were 9.90%, 2.37 g/cm3and 2034 MPa, respectively. Under natural soil condition and the condition of cutting in both sides of the soil, randomly select 10 beet samples and the statistical results of the required pulling force are shown in table 4. The pulling force required to pull the sugar beet out is significantly reduced after the soil treatment and the reducing amplitude is about 30%. Fig.3Frequency distribution of underground depth of tubers Fig.4Frequency distribution of aboveground height of tubers Fig.5Frequency distribution of major axis length of maximum cross section of tubers 增刊 2王方艳等：糖用甜菜物理特性试验分析 301 Fig.6Frequency distribution of length of tubers Fig.7Frequency distribution of tubers weight Table 4Pulling force of sugar beet Pulling force/N Statistical indicators Maximum value Minimum value Average value Standard deviation Coefficient of variation Natural soil490242365980.26 loosen soil390114259880.33 Analysis of correlation of the factors using the statistical software SPSS is shown in Table 5. The results showed that the weight of root tuber, the major and minor axis of the ellipse of the maximum cross section and the length of root tuber are positively correlated at the 0.01 level (bilateral). The weights of root tubers were increased as the increases of geometric size of root tuber. Size of the minor axis of the ellipse has more influence on the weight of root tuber than that of the major and the length of root tuber, and there is greater correlation between the major and the minor axis of the ellipse of the cross section. The pulling force of sugar beet has positive relationship with the weight of root tuber and the minor axis of the ellipse at the 0.1 level (bilateral). The length of root tuber and the number of roots whose diameter is over 10 mm have linear correlation at the 0.05 level (bilateral). The number of roots whos