HighlightsThis article presents a shearing and breaking device for mulch film and stalk mixtures after mechanized recovery.The focus is on a curved V-shaped mechanism with three-dimensional precompression and shearing functions.The device can efficiently and continuously perform film crushing, stalk crushing, and entanglement breaking.The crushed film and stalk mixture is conducive to material separation, further treatment, and recycling.Abstract. Because the mixture of mulch film and stalks collected in harvested cotton fields in Xinjiang, China, cannot be separated mechanically, a technical solution for shearing and breaking is proposed. This study designed a shearing and breaking device for film and stalk mixtures that can continuously perform film crushing, stalk crushing, and entanglement breaking. The design focuses on a curved V-shaped shearing mechanism, which provides three-dimensional shearing and improves the crushing of film and stalks. The linear speed of the conveying rollers (x1), the working angle of the shearer (x2), and the speed of the shearer spindle (x3) were selected as influencing factors, and the crushed film rate (Ph), crushed stalk rate (Gh), and broken entanglement rate (Kh) were used as evaluation indexes in quadratic orthogonal rotation combination tests. The test results were analyzed with Design-Expert software, and a regression model between each factor and the evaluation indexes was established to analyze the significance of each factor’s influence. The results showed that the influences of the three factors on Ph in descending order were x3, x2, and x1. The order of influence on Gh and Kh was x3, x1, and x2. The optimization module in the software was used for parameter optimization, and the optimal combination of working parameters of the device was x1 = 0.98 m s-1, x2 = 153°, and x3 = 753 r min-1. The optimized parameter combination was tested and verified, and the results were Ph = 77.28%, Gh = 87.78%, and Kh = 85.30%. The test results are basically consistent with the predicted values, and the optimized working parameters are reliable and can meet the requirements for the shear fracture of film and stalk mixtures. This research provides a technical reference for the cutting and crushing of complex mixed solid materials. Keywords: Agricultural machinery, Curved V-shaped moving knife, Design, Film and stalk mixture, Parameter optimization.
介绍了一种机械化回收后的地膜秸秆混合料剪切破碎装置。重点研究了具有三维预压和剪切功能的弯曲v形机构。该装置能高效、连续地进行薄膜破碎、秸秆破碎、缠结破碎。粉碎后的膜秆混合物有利于物料分离、进一步处理和回收。针对新疆棉田采收地膜与秸秆混交物无法机械分离的问题，提出了一种剪切破碎的技术解决方案。本研究设计了一种膜茎混合料剪切破碎装置，可连续进行膜破碎、秸秆破碎、缠结破碎。设计的重点是一种弯曲的v型剪切机构，它提供了三维剪切，提高了薄膜和秸秆的破碎程度。选取输送辊线速度(x1)、采煤机工作角度(x2)、采煤机主轴转速(x3)作为影响因素，以破碎膜率(Ph)、破碎秸秆率(Gh)、破碎缠结率(Kh)作为二次正交旋转组合试验的评价指标。采用Design-Expert软件对试验结果进行分析，建立各因素与评价指标之间的回归模型，分析各因素影响的显著性。结果表明，3种因素对Ph的影响程度由大到小依次为x3、x2、x1。对Gh和Kh的影响顺序依次为x3、x1和x2。利用软件中的优化模块进行参数优化，得到器件工作参数的最优组合为x1 = 0.98 m s-1, x2 = 153°，x3 = 753 r min-1。对优化后的参数组合进行了试验验证，结果为Ph = 77.28%， Gh = 87.78%， Kh = 85.30%。试验结果与预测值基本一致，优化后的工作参数可靠，能够满足膜秆混合料剪切断裂的要求。该研究为复杂混合固体材料的切割破碎提供了技术参考。关键词:农业机械，弯v形动刀，设计，膜秆混合料，参数优化
{"title":"Design and Testing of a Shearing and Breaking Device for Mulch Film and Cotton Stalk Mixtures","authors":"Pan Feng, B. Hu, L. Xin, Guo Mengyu, He Haomeng","doi":"10.13031/TRANS.14261","DOIUrl":"https://doi.org/10.13031/TRANS.14261","url":null,"abstract":"HighlightsThis article presents a shearing and breaking device for mulch film and stalk mixtures after mechanized recovery.The focus is on a curved V-shaped mechanism with three-dimensional precompression and shearing functions.The device can efficiently and continuously perform film crushing, stalk crushing, and entanglement breaking.The crushed film and stalk mixture is conducive to material separation, further treatment, and recycling.Abstract. Because the mixture of mulch film and stalks collected in harvested cotton fields in Xinjiang, China, cannot be separated mechanically, a technical solution for shearing and breaking is proposed. This study designed a shearing and breaking device for film and stalk mixtures that can continuously perform film crushing, stalk crushing, and entanglement breaking. The design focuses on a curved V-shaped shearing mechanism, which provides three-dimensional shearing and improves the crushing of film and stalks. The linear speed of the conveying rollers (x1), the working angle of the shearer (x2), and the speed of the shearer spindle (x3) were selected as influencing factors, and the crushed film rate (Ph), crushed stalk rate (Gh), and broken entanglement rate (Kh) were used as evaluation indexes in quadratic orthogonal rotation combination tests. The test results were analyzed with Design-Expert software, and a regression model between each factor and the evaluation indexes was established to analyze the significance of each factor’s influence. The results showed that the influences of the three factors on Ph in descending order were x3, x2, and x1. The order of influence on Gh and Kh was x3, x1, and x2. The optimization module in the software was used for parameter optimization, and the optimal combination of working parameters of the device was x1 = 0.98 m s-1, x2 = 153°, and x3 = 753 r min-1. The optimized parameter combination was tested and verified, and the results were Ph = 77.28%, Gh = 87.78%, and Kh = 85.30%. The test results are basically consistent with the predicted values, and the optimized working parameters are reliable and can meet the requirements for the shear fracture of film and stalk mixtures. This research provides a technical reference for the cutting and crushing of complex mixed solid materials. Keywords: Agricultural machinery, Curved V-shaped moving knife, Design, Film and stalk mixture, Parameter optimization.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"42 1","pages":"545-555"},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76716383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Enrique Orozco-López, R. Muñoz‐Carpena, B. Gao, G. Fox
Three MATLAB code files used in the development of the article "High-Resolution Pore-Scale Water Content Measurement in a Translucent Soil Profile from Light Transmission." In addition, examples of the datasets required to compute the above mentioned code are provided, including images and spreadsheets.
{"title":"Supplemental information for \"High-resolution Pore-scale Water Content Measurement in a Translucent Soil Profile from Light Transmission\"","authors":"Enrique Orozco-López, R. Muñoz‐Carpena, B. Gao, G. Fox","doi":"10.13031/TRANS.14292","DOIUrl":"https://doi.org/10.13031/TRANS.14292","url":null,"abstract":"Three MATLAB code files used in the development of the article \"High-Resolution Pore-Scale Water Content Measurement in a Translucent Soil Profile from Light Transmission.\" In addition, examples of the datasets required to compute the above mentioned code are provided, including images and spreadsheets.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"29 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79901050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Khand, N. Bhattarai, S. Taghvaeian, P. Wagle, P. Gowda, P. Alderman
Highlights Three contextual-based (CB) and two pixel-based (PB) models were evaluated to estimate ET of rainfed winter wheat. Instantaneous available energy estimation and ET upscaling impacted model performance. The CB models performed better at instantaneous and daily scales compared to the PB models. ET estimation biases increased during low vegetation and drier conditions, especially for the PB models. Abstract. Surface energy balance (SEB) models based on thermal remote sensing data are widely used in research applications to map evapotranspiration (ET) across various landscapes. However, their ability to capture ET from winter wheat remains underexplored, especially in practical applications such as integrated resource management and drought preparedness. Investigating winter wheat ET dynamics is important in agricultural regions such as the Southern Great Plains of the U.S., where winter wheat is extensively cultivated. The goal of this study was to evaluate the performance of five fully automated SEB models, three contextual-based (CB) and two pixel-based (PB), in estimating instantaneous and daily ET of winter wheat by comparing the model results with flux tower observations. The CB models included Surface Energy Balance Algorithm for Land (SEBAL), Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC), and Triangular Vegetation Temperature (TVT). The PB models included Surface Energy Balance System (SEBS) and Two-Source Energy Balance (TSEB). Model evaluation during two winter wheat growing seasons (2016-2018) using 28 Landsat images showed that the instantaneous ET estimates from METRIC and TSEB had the smallest (RMSE = 0.14 mm h-1) and largest (RMSE = 0.27 mm h-1) errors, respectively. At the daily scale, SEBAL was the best performing model (RMSE = 1.0 mm d-1), followed by TVT (RMSE = 1.1 mm d-1), METRIC (RMSE = 1.2 mm d-1), SEBS (RMSE = 1.3 mm d-1), and TSEB (RMSE = 1.5 mm d-1). Overall, the CB models provided smaller errors than the PB models. Larger errors in daily ET estimation were observed during low vegetation and drier conditions, especially for the PB models.
利用3种基于情景的(CB)模型和2种基于像元的(PB)模型估算了旱作冬小麦的蒸散发。瞬时可用能量估计和ET上尺度影响模型性能。与PB模型相比，CB模型在瞬时尺度和日尺度上表现较好。在低植被和干旱条件下，ET估算偏差增大，特别是PB模式。摘要基于热遥感数据的地表能量平衡(SEB)模型被广泛用于研究不同景观的蒸散发(ET)。然而，它们从冬小麦中捕获ET的能力仍未得到充分探索，特别是在综合资源管理和抗旱准备等实际应用中。在美国南部大平原等广泛种植冬小麦的农业地区，研究冬小麦的ET动态是很重要的。本研究的目的是通过将模型结果与通量塔观测结果进行比较，评估5个全自动SEB模型(3个基于情境(CB)和2个基于像素(PB))在估算冬小麦瞬时和日蒸散方面的性能。CB模型包括陆地表面能量平衡算法(SEBAL)、基于内化定标的高分辨率蒸散发映射(METRIC)和三角形植被温度(TVT)。PB模型包括表面能量平衡系统(SEBS)和双源能量平衡系统(TSEB)。利用28幅Landsat影像对两个冬小麦生长期(2016-2018)的模型进行评估，结果表明，METRIC和TSEB估算的瞬时ET分别具有最小(RMSE = 0.14 mm h-1)和最大(RMSE = 0.27 mm h-1)误差。在日尺度上，SEBAL模型表现最佳(RMSE = 1.0 mm d-1)，其次是TVT (RMSE = 1.1 mm d-1)、METRIC (RMSE = 1.2 mm d-1)、SEBS (RMSE = 1.3 mm d-1)和TSEB (RMSE = 1.5 mm d-1)。总体而言，CB模型提供的误差小于PB模型。低植被和干旱条件下的日蒸散发估算误差较大，特别是PB模式。
{"title":"Modeling Evapotranspiration of Winter Wheat Using Contextual and Pixel-Based Surface Energy Balance Models","authors":"K. Khand, N. Bhattarai, S. Taghvaeian, P. Wagle, P. Gowda, P. Alderman","doi":"10.13031/TRANS.14087","DOIUrl":"https://doi.org/10.13031/TRANS.14087","url":null,"abstract":"Highlights Three contextual-based (CB) and two pixel-based (PB) models were evaluated to estimate ET of rainfed winter wheat. Instantaneous available energy estimation and ET upscaling impacted model performance. The CB models performed better at instantaneous and daily scales compared to the PB models. ET estimation biases increased during low vegetation and drier conditions, especially for the PB models. Abstract. Surface energy balance (SEB) models based on thermal remote sensing data are widely used in research applications to map evapotranspiration (ET) across various landscapes. However, their ability to capture ET from winter wheat remains underexplored, especially in practical applications such as integrated resource management and drought preparedness. Investigating winter wheat ET dynamics is important in agricultural regions such as the Southern Great Plains of the U.S., where winter wheat is extensively cultivated. The goal of this study was to evaluate the performance of five fully automated SEB models, three contextual-based (CB) and two pixel-based (PB), in estimating instantaneous and daily ET of winter wheat by comparing the model results with flux tower observations. The CB models included Surface Energy Balance Algorithm for Land (SEBAL), Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC), and Triangular Vegetation Temperature (TVT). The PB models included Surface Energy Balance System (SEBS) and Two-Source Energy Balance (TSEB). Model evaluation during two winter wheat growing seasons (2016-2018) using 28 Landsat images showed that the instantaneous ET estimates from METRIC and TSEB had the smallest (RMSE = 0.14 mm h-1) and largest (RMSE = 0.27 mm h-1) errors, respectively. At the daily scale, SEBAL was the best performing model (RMSE = 1.0 mm d-1), followed by TVT (RMSE = 1.1 mm d-1), METRIC (RMSE = 1.2 mm d-1), SEBS (RMSE = 1.3 mm d-1), and TSEB (RMSE = 1.5 mm d-1). Overall, the CB models provided smaller errors than the PB models. Larger errors in daily ET estimation were observed during low vegetation and drier conditions, especially for the PB models.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"73 1","pages":"507-519"},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80552433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
HighlightsBlack soldier fly larvae can be used to convert agricultural wastes into animal feed.A prototype automated incubation system for producing black soldier fly larvae was designed and tested.The system was successful in growing larvae to a harvestable size.The system retained metabolic heat generated by larval and microbial activity.Abstract. Biological conversion of agricultural wastes into animal feed ingredients using larvae of black soldier fly, (Hermetia illucens) is a promising technology that improves the sustainability of agriculture. We designed and tested a prototype automated incubation system for producing black soldier fly larvae. The system consisted of six 50 L plastic bins enclosed on a ventilated metal rack (178 cm high, 66 cm wide). Water was supplied to maintain a moisture level of about 60% in each bin via soaker hoses connected to sensor-activated solenoid valves. The system was successful in maintaining moisture and temperature suitable for larval development and for growing larvae to harvestable size with minimal labor and energy consumption. Biological activity in the bins generated a considerable amount of metabolic heat, most of which was trapped in the substrate in each bin. This heat may be valuable for rearing black soldier fly larvae in areas with cool climates because this species has low tolerance of cold temperatures but challenging in areas with warm climates. Keywords: Biological conversion, Black soldier fly, Metabolic heat generation, Waste management.
{"title":"An Automated Incubator for Rearing Black Soldier Fly Larvae (Hermetia illucens)","authors":"P. Erbland, A. Alyokhin, Michael Peterson","doi":"10.13031/trans.14623","DOIUrl":"https://doi.org/10.13031/trans.14623","url":null,"abstract":"HighlightsBlack soldier fly larvae can be used to convert agricultural wastes into animal feed.A prototype automated incubation system for producing black soldier fly larvae was designed and tested.The system was successful in growing larvae to a harvestable size.The system retained metabolic heat generated by larval and microbial activity.Abstract. Biological conversion of agricultural wastes into animal feed ingredients using larvae of black soldier fly, (Hermetia illucens) is a promising technology that improves the sustainability of agriculture. We designed and tested a prototype automated incubation system for producing black soldier fly larvae. The system consisted of six 50 L plastic bins enclosed on a ventilated metal rack (178 cm high, 66 cm wide). Water was supplied to maintain a moisture level of about 60% in each bin via soaker hoses connected to sensor-activated solenoid valves. The system was successful in maintaining moisture and temperature suitable for larval development and for growing larvae to harvestable size with minimal labor and energy consumption. Biological activity in the bins generated a considerable amount of metabolic heat, most of which was trapped in the substrate in each bin. This heat may be valuable for rearing black soldier fly larvae in areas with cool climates because this species has low tolerance of cold temperatures but challenging in areas with warm climates. Keywords: Biological conversion, Black soldier fly, Metabolic heat generation, Waste management.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"21 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89545549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shuo Wu, Jizhan Liu, Jiangshan Wang, Dianhe Hao, Rongkai Wang
Highlights A visualization method for the motion of strawberry leaves in an air-assisted spray field is proposed. Strawberry leaves showed two motion states in different critical velocity ranges of the sprayer airflow. The airflow instability and the turbulence effect are considered important factors for the leaf vibrations. A strawberry leaf azimuth angle in the range of 90° to 270° can provide good deposition with smaller droplets. Abstract. The reasonable motion of crop plants in an air-assisted spray field can improve droplet deposition. Therefore, this study focuses on the motion of strawberry leaves and the droplet deposition mechanism in an air-assisted spray field. First, this study proposes a descriptive method for strawberry leaf motion in an air-assisted spray field and clarifies the important influence of strawberry leaf motion on droplet deposition. Second, an experiment was performed on the motion and droplet capture of single strawberry leaves in multi-position postures in an air-assisted spray field. The results showed that the leaves had two motion states (i.e., low amplitude with low frequency and high amplitude with high frequency) at different airflow velocities and inclination angles, and the critical airflow velocity corresponding to the two motion states was determined to be 8.7 m s-1. When the azimuth angle of the strawberry leaves is in the range of 90° to 270°, a reasonable inclination angle of the airflow and the high frequency and high amplitude vibration state of the leaves driven by the airflow will provide good deposition and canopy penetration of droplets with smaller diameters.
提出了一种空气辅助喷雾场中草莓叶片运动的可视化方法。草莓叶片在喷雾器气流的不同临界速度范围内呈现两种运动状态。气流不稳定性和湍流效应是引起叶片振动的重要因素。草莓叶片方位角在90°~ 270°范围内，雾滴较小，沉积效果较好。摘要在空气辅助喷雾场中，作物的合理运动可以改善液滴的沉积。因此，本研究重点研究了空气辅助喷雾场中草莓叶片的运动和液滴沉积机理。首先，本文提出了一种空气辅助喷雾场中草莓叶片运动的描述方法，阐明了草莓叶片运动对雾滴沉积的重要影响。其次，在空气辅助喷雾场中，对草莓单叶在多种姿态下的运动和液滴捕获进行了实验研究。结果表明:叶片在不同气流速度和倾角下存在低幅低频和高幅高频两种运动状态，确定了这两种运动状态对应的临界气流速度为8.7 m s-1;当草莓叶片的方位角在90°~ 270°范围内时，合理的气流倾角和气流驱动下叶片的高频、高振幅振动状态将为粒径较小的液滴提供良好的沉积和冠层穿透。
{"title":"The Motion of Strawberry Leaves in an Air-Assisted Spray Field and its Influence on Droplet Deposition","authors":"Shuo Wu, Jizhan Liu, Jiangshan Wang, Dianhe Hao, Rongkai Wang","doi":"10.13031/trans.14143","DOIUrl":"https://doi.org/10.13031/trans.14143","url":null,"abstract":"Highlights A visualization method for the motion of strawberry leaves in an air-assisted spray field is proposed. Strawberry leaves showed two motion states in different critical velocity ranges of the sprayer airflow. The airflow instability and the turbulence effect are considered important factors for the leaf vibrations. A strawberry leaf azimuth angle in the range of 90° to 270° can provide good deposition with smaller droplets. Abstract. The reasonable motion of crop plants in an air-assisted spray field can improve droplet deposition. Therefore, this study focuses on the motion of strawberry leaves and the droplet deposition mechanism in an air-assisted spray field. First, this study proposes a descriptive method for strawberry leaf motion in an air-assisted spray field and clarifies the important influence of strawberry leaf motion on droplet deposition. Second, an experiment was performed on the motion and droplet capture of single strawberry leaves in multi-position postures in an air-assisted spray field. The results showed that the leaves had two motion states (i.e., low amplitude with low frequency and high amplitude with high frequency) at different airflow velocities and inclination angles, and the critical airflow velocity corresponding to the two motion states was determined to be 8.7 m s-1. When the azimuth angle of the strawberry leaves is in the range of 90° to 270°, a reasonable inclination angle of the airflow and the high frequency and high amplitude vibration state of the leaves driven by the airflow will provide good deposition and canopy penetration of droplets with smaller diameters.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"57 1","pages":"83-93"},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90989264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
HighlightsA discrete element simulation model was used to improve the performance of a corn silage crushing and throwing device.Feed rate, crushing speed, and dial speed were used as the test factors, and the average cutting force and average energy loss were used as the evaluation indexes in orthogonal testing.The order of significance of the factors was crushing speed > feed rate > dial speed for average cutting force and crushing speed > dial speed > feed rate for average energy loss.Abstract. To improve the performance of a corn silage crushing and throwing device and address the problems of low crushing quality and high power consumption, a discrete element simulation model of a corn silage crushing and throwing device and granular straw was established based on discrete element theory using EDEM, a general-purpose CAE software program designed with modern discrete element model technology to simulate and analyze particle processing and production operations. The average cutting force and average energy loss of the particles were the evaluation indexes, and the influence of feed rate, crushing speed, and dial speed on the evaluation indexes was analyzed using single-factor simulation tests. The order of significance was crushing speed > feed rate > dial speed for the average cutting force and crushing speed > dial speed > feed rate for the average energy loss. Using multi-objective optimization, the optimal combination of feed rate, crushing speed, and dial speed was 3.52 kg s-1, 892.06 rpm, and 1502 rpm, respectively. With the optimal parameters, the average cutting force was 58.20 N and the average energy loss was 0.85 J. To verify the feasibility of the EDEM simulation, field tests were conducted using a trial-produced device, with the acceptability of straw crushing and power consumption as the test indicators. During the field tests, the feed rate, crushing speed, and dial speed were set to 3.52 kg s-1, 890 rpm, and 1500 rpm, respectively. The field tests showed that the acceptability of straw crushing and the power consumption were 93.60% and 6.73 kW·h, respectively, with the optimal parameters, which satisfied the corn silage crushing standard and provides a theoretical and scientific basis for the design and optimization of the device. Keywords: Corn silage, Crushing and throwing device, Discrete element simulation, Motion simulation, Multi-objective optimization method.
采用离散元仿真模型对玉米青贮粉碎抛撒装置的性能进行了改进。以进给速度、破碎速度和拨盘速度为试验因素，以平均切削力和平均能量损失为正交试验的评价指标。各因素对平均切削力的影响程度依次为破碎速度>进给速度>拨盘速度，对平均能量损失的影响程度依次为破碎速度>拨盘速度>进给速度。为了提高玉米青贮破碎抛撒装置的性能，解决玉米青贮破碎抛撒装置破碎质量低、能耗大的问题，基于离散元理论，利用现代离散元模型技术设计的通用CAE软件EDEM，建立了玉米青贮破碎抛撒装置和颗粒秸秆的离散元仿真模型。以颗粒的平均切削力和平均能量损失为评价指标，通过单因素模拟试验分析了进给量、破碎速度和拨盘速度对评价指标的影响。平均切削力的显著性顺序为破碎速度>进给速度>拨盘速度，平均能量损失的显著性顺序为破碎速度>拨盘速度>进给速度。采用多目标优化方法，得到给料速度、破碎速度和拨盘速度的最优组合分别为3.52 kg s-1、892.06 rpm和1502 rpm。在优化参数下，平均切割力为58.20 N，平均能量损失为0.85 j。为了验证EDEM模拟的可行性，利用试制装置进行了现场试验，以秸秆破碎可接受性和能耗为试验指标。在现场试验中，给料速度、破碎速度和拨盘速度分别设置为3.52 kg s-1、890 rpm和1500 rpm。现场试验结果表明，秸秆破碎接受度为93.60%，能耗为6.73 kW·h，优化参数满足玉米青贮破碎标准，为装置的设计和优化提供了理论和科学依据。关键词:玉米青贮，破碎抛掷装置，离散元仿真，运动仿真，多目标优化方法
{"title":"Discrete Element-Based Optimization Parameters of an Experimental Corn Silage Crushing and Throwing Device","authors":"Shenghe Bai, Qizhi Yang, K. Niu, Zhao Bo, Liming Zhou, Yanwei Yuan","doi":"10.13031/trans.14463","DOIUrl":"https://doi.org/10.13031/trans.14463","url":null,"abstract":"HighlightsA discrete element simulation model was used to improve the performance of a corn silage crushing and throwing device.Feed rate, crushing speed, and dial speed were used as the test factors, and the average cutting force and average energy loss were used as the evaluation indexes in orthogonal testing.The order of significance of the factors was crushing speed > feed rate > dial speed for average cutting force and crushing speed > dial speed > feed rate for average energy loss.Abstract. To improve the performance of a corn silage crushing and throwing device and address the problems of low crushing quality and high power consumption, a discrete element simulation model of a corn silage crushing and throwing device and granular straw was established based on discrete element theory using EDEM, a general-purpose CAE software program designed with modern discrete element model technology to simulate and analyze particle processing and production operations. The average cutting force and average energy loss of the particles were the evaluation indexes, and the influence of feed rate, crushing speed, and dial speed on the evaluation indexes was analyzed using single-factor simulation tests. The order of significance was crushing speed > feed rate > dial speed for the average cutting force and crushing speed > dial speed > feed rate for the average energy loss. Using multi-objective optimization, the optimal combination of feed rate, crushing speed, and dial speed was 3.52 kg s-1, 892.06 rpm, and 1502 rpm, respectively. With the optimal parameters, the average cutting force was 58.20 N and the average energy loss was 0.85 J. To verify the feasibility of the EDEM simulation, field tests were conducted using a trial-produced device, with the acceptability of straw crushing and power consumption as the test indicators. During the field tests, the feed rate, crushing speed, and dial speed were set to 3.52 kg s-1, 890 rpm, and 1500 rpm, respectively. The field tests showed that the acceptability of straw crushing and the power consumption were 93.60% and 6.73 kW·h, respectively, with the optimal parameters, which satisfied the corn silage crushing standard and provides a theoretical and scientific basis for the design and optimization of the device. Keywords: Corn silage, Crushing and throwing device, Discrete element simulation, Motion simulation, Multi-objective optimization method.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"20 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91228957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
X. Zhang, Mingxi Shen, Jie Chen, J. Homan, P. Busteed
HighlightsNine statistical downscaling methods from three downscaling categories were evaluated.Weather generator-based methods had advantages in simulating non-stationary precipitation.Differences in downscaling performance were smaller within each category than between categories.The performance of each downscaling method varied with climate conditions.Abstract. Spatial discrepancy between global climate model (GCM) projections and the climate data input required by hydrological models is a major limitation for assessing the impact of climate change on soil erosion and crop production at local scales. Statistical downscaling techniques are widely used to correct biases of GCM projections. The objective of this study was to evaluate the ability of nine statistical downscaling methods from three available statistical downscaling categories to simulate daily precipitation distribution, frequency, and temporal sequence at four Oklahoma weather stations representing arid to humid climate regions. The three downscaling categories included perfect prognosis (PP), model output statistics (MOS), and stochastic weather generator (SWG). To minimize the effect of GCM projection error on downscaling quality, the National Centers for Environmental Prediction (NCEP) Reanalysis 1 data at a 2.5° grid spacing (treated as observed grid data) were downscaled to the four weather stations (representing arid, semi-arid, sub humid, and humid regions) using the nine downscaling methods. The station observations were divided into calibration and validation periods in a way that maximized the differences in annual precipitation means between the two periods for assessing the ability of each method in downscaling non-stationary climate changes. All methods were ranked with three metrics (Euclidean distance, sum of absolute relative error, and absolute error) for their ability in simulating precipitation amounts at daily, monthly, yearly, and annual maximum scales. After eliminating the poorest two performers in simulating precipitation mean, distribution, frequency, and temporal sequence, the top four remaining methods in ascending order were Distribution-based Bias Correction (DBC), Generator for Point Climate Change (GPCC), SYNthetic weather generaTOR (SYNTOR), and LOCal Intensity scaling (LOCI). DBC and LOCI are bias-correction methods, and GPCC and SYNTOR are generator-based methods. The differences in performances among the downscaling methods were smaller within each downscaling category than between the categories. The performance of each method varied with the climate conditions of each station. Overall results indicated that the SWG methods had certain advantages in simulating daily precipitation distribution, frequency, and temporal sequence for non-stationary climate changes. Keywords: Climate change, Climate downscaling, Downscaling method evaluation, Statistical downscaling.
{"title":"Evaluation of Statistical Downscaling Methods for Simulating Daily Precipitation Distribution, Frequency, and Temporal Sequence","authors":"X. Zhang, Mingxi Shen, Jie Chen, J. Homan, P. Busteed","doi":"10.13031/TRANS.14097","DOIUrl":"https://doi.org/10.13031/TRANS.14097","url":null,"abstract":"HighlightsNine statistical downscaling methods from three downscaling categories were evaluated.Weather generator-based methods had advantages in simulating non-stationary precipitation.Differences in downscaling performance were smaller within each category than between categories.The performance of each downscaling method varied with climate conditions.Abstract. Spatial discrepancy between global climate model (GCM) projections and the climate data input required by hydrological models is a major limitation for assessing the impact of climate change on soil erosion and crop production at local scales. Statistical downscaling techniques are widely used to correct biases of GCM projections. The objective of this study was to evaluate the ability of nine statistical downscaling methods from three available statistical downscaling categories to simulate daily precipitation distribution, frequency, and temporal sequence at four Oklahoma weather stations representing arid to humid climate regions. The three downscaling categories included perfect prognosis (PP), model output statistics (MOS), and stochastic weather generator (SWG). To minimize the effect of GCM projection error on downscaling quality, the National Centers for Environmental Prediction (NCEP) Reanalysis 1 data at a 2.5° grid spacing (treated as observed grid data) were downscaled to the four weather stations (representing arid, semi-arid, sub humid, and humid regions) using the nine downscaling methods. The station observations were divided into calibration and validation periods in a way that maximized the differences in annual precipitation means between the two periods for assessing the ability of each method in downscaling non-stationary climate changes. All methods were ranked with three metrics (Euclidean distance, sum of absolute relative error, and absolute error) for their ability in simulating precipitation amounts at daily, monthly, yearly, and annual maximum scales. After eliminating the poorest two performers in simulating precipitation mean, distribution, frequency, and temporal sequence, the top four remaining methods in ascending order were Distribution-based Bias Correction (DBC), Generator for Point Climate Change (GPCC), SYNthetic weather generaTOR (SYNTOR), and LOCal Intensity scaling (LOCI). DBC and LOCI are bias-correction methods, and GPCC and SYNTOR are generator-based methods. The differences in performances among the downscaling methods were smaller within each downscaling category than between the categories. The performance of each method varied with the climate conditions of each station. Overall results indicated that the SWG methods had certain advantages in simulating daily precipitation distribution, frequency, and temporal sequence for non-stationary climate changes. Keywords: Climate change, Climate downscaling, Downscaling method evaluation, Statistical downscaling.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"72 1","pages":"771-784"},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77477830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Solé-Torres, F. Lamm, M. Duran–Ros, G. Arbat, F. R. Cartagena, J. Puig-Bargués
HighlightsDistribution uniformity of the lower quartile (DUlq) was assessed in three microirrigation subunits with three procedures that used different locations and different numbers of sampled emitters.Using reclaimed effluent as the water source, performance was periodically measured for a total duration of 1000 h.Emitter clogging and the locations of sampled emitters greatly affected DUlq.None of the procedures accurately assessed DUlq if more than 4% of the emitters were fully clogged.Abstract. Proper water distribution uniformity is important for successful use of microirrigation systems. Consequently, consistent system monitoring and periodic distribution uniformity assessments can help determine the performance of a microirrigation system and identify possible problems that should be corrected. When using irrigation water with a greater clogging risk, such as reclaimed effluent, emitter clogging can seriously affect distribution uniformity. In this study, distribution uniformity was measured at three times (0 h, 500 h, and 1000 h of operation) in a microirrigation system that used reclaimed effluent. Emitter discharge values were obtained for each emitter in the system (three subunits consisting of four driplines each with 226 pressure-compensating emitters on each dripline), and the distribution uniformity of the low quartile (DUlq) was calculated for each subunit. These comprehensive DUlq values were compared with those calculated by three estimation procedures developed by Merriam and Keller, Burt, and Juana et al., which use different sampling locations and different numbers of sampling points. Results showed strong influence of emitter clogging and the location of the sampled emitters on DUlq values. Using this data set, the Merriam and Keller procedure had the greatest root mean square error (RMSE = 41.8%), the Burt procedure resulted in an intermediate value (RMSE = 5.9%), and the Juana et al. procedure had the lowest (RMSE = 3.2%) when most of the completely clogged emitters (about 1% of the total) were located at the ends of the driplines. Further speculative analysis in which complete clogging was allowed to migrate to the farthest distal emitters for the Burt and Juana et al. procedures indicated that none of the procedures accurately assessed the actual complete DUlq. These results suggest that none of these procedures alone are successful at assessing system-wide distribution uniformity when substantial clogging exists. Keywords: Drip irrigation, Effluent, Emitter clogging, Flow variation, Wastewater.
{"title":"Assessment of Microirrigation Field Distribution Uniformity Procedures for Pressure-Compensating Emitters under Potential Clogging Conditions","authors":"C. Solé-Torres, F. Lamm, M. Duran–Ros, G. Arbat, F. R. Cartagena, J. Puig-Bargués","doi":"10.13031/trans.14486","DOIUrl":"https://doi.org/10.13031/trans.14486","url":null,"abstract":"HighlightsDistribution uniformity of the lower quartile (DUlq) was assessed in three microirrigation subunits with three procedures that used different locations and different numbers of sampled emitters.Using reclaimed effluent as the water source, performance was periodically measured for a total duration of 1000 h.Emitter clogging and the locations of sampled emitters greatly affected DUlq.None of the procedures accurately assessed DUlq if more than 4% of the emitters were fully clogged.Abstract. Proper water distribution uniformity is important for successful use of microirrigation systems. Consequently, consistent system monitoring and periodic distribution uniformity assessments can help determine the performance of a microirrigation system and identify possible problems that should be corrected. When using irrigation water with a greater clogging risk, such as reclaimed effluent, emitter clogging can seriously affect distribution uniformity. In this study, distribution uniformity was measured at three times (0 h, 500 h, and 1000 h of operation) in a microirrigation system that used reclaimed effluent. Emitter discharge values were obtained for each emitter in the system (three subunits consisting of four driplines each with 226 pressure-compensating emitters on each dripline), and the distribution uniformity of the low quartile (DUlq) was calculated for each subunit. These comprehensive DUlq values were compared with those calculated by three estimation procedures developed by Merriam and Keller, Burt, and Juana et al., which use different sampling locations and different numbers of sampling points. Results showed strong influence of emitter clogging and the location of the sampled emitters on DUlq values. Using this data set, the Merriam and Keller procedure had the greatest root mean square error (RMSE = 41.8%), the Burt procedure resulted in an intermediate value (RMSE = 5.9%), and the Juana et al. procedure had the lowest (RMSE = 3.2%) when most of the completely clogged emitters (about 1% of the total) were located at the ends of the driplines. Further speculative analysis in which complete clogging was allowed to migrate to the farthest distal emitters for the Burt and Juana et al. procedures indicated that none of the procedures accurately assessed the actual complete DUlq. These results suggest that none of these procedures alone are successful at assessing system-wide distribution uniformity when substantial clogging exists. Keywords: Drip irrigation, Effluent, Emitter clogging, Flow variation, Wastewater.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"42 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81743408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
HighlightsAn adapted annular denuder system (ADS) was implemented in a broiler facility to measure secondary aerosols.Results show that secondary aerosols were not always associated with ammonium or ammonia.Chloride aerosols were significant in comparison to other species and were present at consistent concentrations.This study concludes that the chloride source was the feed in the feeding pans.Abstract. Fine particulate matter (PM2.5) is present in animal housing facilities from both primary and secondary sources. Measuring secondary aerosols in harsh environments with high gas and particulate concentrations, such as poultry housing facilities, is an ongoing challenge. This study presents the results from the implementation of an adapted annular denuder system (ADS) used to measure secondary PM2.5 from inside a broiler facility in Ontario, Canada. Results from this work show that secondary aerosols formed the majority of total PM2.5 during the early portion of the growth cycle. It was further determined that the ion balance between ammonium and anions was not consistent, leading to the conclusion that a significant portion of the aerosol species are associated with a previously unidentified source that is not necessarily due to secondary reactions. Keywords: Ammonia, Annular denuder system, Particulate matter, Poultry, Secondary aerosols.
{"title":"Aerosol and Gas Phase Concentrations from an Adapted Annular Denuder System in a Broiler Housing Facility","authors":"J. Spencer, Vernon Osborne, B. V. Heyst","doi":"10.13031/trans.14050","DOIUrl":"https://doi.org/10.13031/trans.14050","url":null,"abstract":"HighlightsAn adapted annular denuder system (ADS) was implemented in a broiler facility to measure secondary aerosols.Results show that secondary aerosols were not always associated with ammonium or ammonia.Chloride aerosols were significant in comparison to other species and were present at consistent concentrations.This study concludes that the chloride source was the feed in the feeding pans.Abstract. Fine particulate matter (PM2.5) is present in animal housing facilities from both primary and secondary sources. Measuring secondary aerosols in harsh environments with high gas and particulate concentrations, such as poultry housing facilities, is an ongoing challenge. This study presents the results from the implementation of an adapted annular denuder system (ADS) used to measure secondary PM2.5 from inside a broiler facility in Ontario, Canada. Results from this work show that secondary aerosols formed the majority of total PM2.5 during the early portion of the growth cycle. It was further determined that the ion balance between ammonium and anions was not consistent, leading to the conclusion that a significant portion of the aerosol species are associated with a previously unidentified source that is not necessarily due to secondary reactions. Keywords: Ammonia, Annular denuder system, Particulate matter, Poultry, Secondary aerosols.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"1 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82065407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
HighlightsCracking and subsequent breakage of rice kernels reduces the marketability and profitability of rice.Pre-milling cracks in rice kernels cause breakage during milling, thereby reducing consumer acceptability.Three types of post-milling cracks reported are: surface, internal, and Hanasaki cracks.Post-milling cracks can be minimized throughout the supply chain.Abstract. Rice is consumed as intact grain, and any broken grains are discounted from the main marketable product. Breakage of rice mainly arises from cracks formed in the endosperm before or after milling. The cracks are formed by stress gradients that arise due to moisture absorption or desorption by grains. As a result of such stress, cracks mostly develop in a direction perpendicular to the length of the grain, making it less physically resistant to the stresses of milling, handling, and soaking processes. Until now, research into rice cracking has mainly focused on minimizing breakage during milling, and no significant knowledge is available on the impact and mechanisms of post-milling cracking and/or breakage and its effect on the downstream quality of rice. This article aims to review the existing information on the causes of rice cracking before and after milling. Keywords: Breakage, Crack, Drying, Glass transition temperature, Hanasaki, Head rice yield, Rice, Tempering.
{"title":"Understanding Pre- and Post-Milling Crack Formation in Rice Grain","authors":"P. Oli, Mark Talbot, P. Snell","doi":"10.13031/trans.14649","DOIUrl":"https://doi.org/10.13031/trans.14649","url":null,"abstract":"HighlightsCracking and subsequent breakage of rice kernels reduces the marketability and profitability of rice.Pre-milling cracks in rice kernels cause breakage during milling, thereby reducing consumer acceptability.Three types of post-milling cracks reported are: surface, internal, and Hanasaki cracks.Post-milling cracks can be minimized throughout the supply chain.Abstract. Rice is consumed as intact grain, and any broken grains are discounted from the main marketable product. Breakage of rice mainly arises from cracks formed in the endosperm before or after milling. The cracks are formed by stress gradients that arise due to moisture absorption or desorption by grains. As a result of such stress, cracks mostly develop in a direction perpendicular to the length of the grain, making it less physically resistant to the stresses of milling, handling, and soaking processes. Until now, research into rice cracking has mainly focused on minimizing breakage during milling, and no significant knowledge is available on the impact and mechanisms of post-milling cracking and/or breakage and its effect on the downstream quality of rice. This article aims to review the existing information on the causes of rice cracking before and after milling. Keywords: Breakage, Crack, Drying, Glass transition temperature, Hanasaki, Head rice yield, Rice, Tempering.","PeriodicalId":23120,"journal":{"name":"Transactions of the ASABE","volume":"8 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73530060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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