通讯机构:
[Yang, L ] W;Wuhan Polytech Univ, Coll Mech Engn, Wuhan 430048, Hubei, Peoples R China.
关键词:
Vertical rice mill;Interaction mechanism;Rice;Discrete element method
摘要:
The external milling vertical rice mill (EMVRM) is one of the new rice milling process equipment. The grains moving and interaction mechanism are basic points for milling, rice blade-sand bar spacing H, sieve structure are important structural parameters need considering. The EMVRM 3D model and DEM contact working model are established. The rice blade spacing H and sieve structure effect on grains motion and interaction in is analyzed. Grains motion velocity and density in milling chamber gradually reduced along axial flow direction. The milling chamber grains average motion velocity difference decreases with spacing H increasing. The grain normal and tangential force show down parabolic relation with axial distance from inlet. The sieve direction has little effect on grain motion velocity and force. Normal and tangential force in milling chamber reduced downward along the axial. The research provides practical guidance for EMVRM mill design.
The external milling vertical rice mill (EMVRM) is one of the new rice milling process equipment. The grains moving and interaction mechanism are basic points for milling, rice blade-sand bar spacing H, sieve structure are important structural parameters need considering. The EMVRM 3D model and DEM contact working model are established. The rice blade spacing H and sieve structure effect on grains motion and interaction in is analyzed. Grains motion velocity and density in milling chamber gradually reduced along axial flow direction. The milling chamber grains average motion velocity difference decreases with spacing H increasing. The grain normal and tangential force show down parabolic relation with axial distance from inlet. The sieve direction has little effect on grain motion velocity and force. Normal and tangential force in milling chamber reduced downward along the axial. The research provides practical guidance for EMVRM mill design.
作者机构:
[Yu Zhai; Jianjun Yang; Xiao Rang; Zean Wang; Houchang Pei; Shaoyun Song] College of Mechanical Engineering, Wuhan Polytechnic University, Wuhan, China
会议名称:
2025 5th International Conference on Artificial Intelligence and Industrial Technology Applications (AIITA)
会议时间:
28 March 2025
会议地点:
Xi'an, China
会议论文集名称:
2025 5th International Conference on Artificial Intelligence and Industrial Technology Applications (AIITA)
关键词:
Steel material defects detection;YOLOv7;Attention mechanism;Data enhancement
摘要:
The detection of steel material defects is vital for enhancing product quality, safety, and reliability. However, conventional deep learning approaches, such as YOLOv7 and SSD, suffer from slow detection speed and suboptimal accuracy. To address these issues, we present an enhanced YOLOv7 algorithm for steel defect detection. Our approach optimizes the YOLOv7 model by integrating ResNet Channel Attention Connection modules into the backbone network to improve feature extraction capabilities. Furthermore, a self-Coordinate Attention mechanism is introduced to enhance detection accuracy. Additionally, we modify downsampling using the unfold model to improve the detection of small objects. Experimental results demonstrate the effectiveness of our proposed enhanced YOLOv7 model in accurately identifying steel defects. Compared to the original model, we achieved an 11.4% increase in mean average precision (mAP) and reduced training time by 2.795 hours.
通讯机构:
[Li, JK ] W;Wuhan Polytech Univ, Sch Mech Engn, Wuhan 430023, Peoples R China.
关键词:
Rice grain pile;Heat and humidity transfer;Simulation test;Simulated granary;Water migration
摘要:
This study addresses the challenge of developing effective strategies to prevent and control the deterioration of stored grain quality caused by biological activities and heating. The unclear mechanisms of water migration and humidity distribution within rice grain piles subjected to localized high temperatures complicate this effort. Using COMSOL simulation and model granaries, the study examines temperature fields, humidity fields, and water migration in high temperature and humidity areas. Results show that within 24–48 h of high-humidity rice exposure to high temperatures, the surrounding grain's temperature rises rapidly, with relative humidity increasing significantly within 48–72 h. The temperature peaks at around 96 h. The influence of high-humidity grain on its surroundings is minimal within the first 36 h, but as temperature increases, the relative humidity of the surrounding grain pile rises faster. The micro-airflow caused by temperature differences drives moist air to migrate to cooler areas, leading to a rise in moisture content in these regions. Therefore, interventions like ventilation and grain turnover should be implemented within 24 h of detecting high-temperature grain, with continuous monitoring of moisture content in adjacent low-temperature areas to prevent further deterioration.
This study addresses the challenge of developing effective strategies to prevent and control the deterioration of stored grain quality caused by biological activities and heating. The unclear mechanisms of water migration and humidity distribution within rice grain piles subjected to localized high temperatures complicate this effort. Using COMSOL simulation and model granaries, the study examines temperature fields, humidity fields, and water migration in high temperature and humidity areas. Results show that within 24–48 h of high-humidity rice exposure to high temperatures, the surrounding grain's temperature rises rapidly, with relative humidity increasing significantly within 48–72 h. The temperature peaks at around 96 h. The influence of high-humidity grain on its surroundings is minimal within the first 36 h, but as temperature increases, the relative humidity of the surrounding grain pile rises faster. The micro-airflow caused by temperature differences drives moist air to migrate to cooler areas, leading to a rise in moisture content in these regions. Therefore, interventions like ventilation and grain turnover should be implemented within 24 h of detecting high-temperature grain, with continuous monitoring of moisture content in adjacent low-temperature areas to prevent further deterioration.
通讯机构:
[Yang, L ] W;Wuhan Polytech Univ, Coll Mech Engn, Wuhan, Peoples R China.
关键词:
crosslink network structure;dry gel;mechanical properties;rice starch gel
摘要:
Starch materials have been widely used in fields of flexible sensing and food 3D printing; rice starch (new source) needs in-depth research for related applications. In this research, a mixing-temperature controlling-cold drying preparation scheme for rice starch gel with stable performance is proposed. In order to in-depth analyze the rice starch internal structural-mechanical behavior, a developed texture analyzer with in situ observation is self-established; the gel internal structure, mechanical behavior, and loading capacity are in-depth analyzed. Effects of rice starch kind (indica, japonica, glutinous) and starch concentration are investigated on internal structure evolution and mechanical behavior. Experimental results show the starch gel is of crosslink network internal structure with pores. The starch dry gel compression force-displacement curve exhibits an S-shaped relation. It can be divided into three stages: elastic deformation, micro-cracking, and overall fracture, matching with rice dry gel internal structure evolution. Rice dry gel peak bearing force order is glutinous starch > indica starch > japonica starch, negatively correlated with internal network structure pore size. The dry gel internal pore size turns out to be small with increasing rice starch concentration. Based on rice starch dry gel mechanical and micro-structure analysis, rice starch gels exhibit optimal structure for application.
期刊:
Results in Engineering,2025年27:106131 ISSN:2590-1230
通讯作者:
Youjun He
作者机构:
[Yin, Qiang; He, Youjun; Liu, Shuai; Liu, Xiaopeng; Zhang, Yonglin; Song, Shaoyun; Li, Hui] School of Mechanical Engineering, Wuhan Polytechnic University, Wuhan 430023, China
通讯机构:
[Youjun He] S;School of Mechanical Engineering, Wuhan Polytechnic University, Wuhan 430023, China
关键词:
paddy grain pile;Heat and moisture coupling;COMSOL;Mechanical Ventilation
摘要:
Temperature and humidity within grain bulks are two critical factors affecting the safe storage duration of grains. Investigating the heat and moisture transfer mechanisms during storage, along with the coupled interactions among various in-silo factors, enables better prediction of grain storage conditions and supports high-quality grain preservation. In this study, a paddy grain bulk exhibiting humidity stratification inside a grain silo is selected as the research subjet. Based on multi-physics coupling theory, a comprehensive study is conducted on the heat and moisture transfer processes in the paddy grain bulk. A coupled heat and moisture transfer model is established under mechanical ventilation conditions according to the principles of mass, energy, and momentum conservation. Experimental validation is conducted using a custom-built grain silo test chamber, in which temperature and humidity data are collected during ventilation and compared with simulation results to assess model accuracy. The results show that the maximum temperature deviation between simulated and measured values at various monitoring points is 0.94 °C, while the relative humidity error remains within 2%, demonstrating the model’s high accuracy and adaptability. Building upon existing heat and moisture modeling efforts, this study further deepens the coupling mechanisms and enables dynamic simulation and quantitative analysis of humidity stratification within the grain bulk. These findings provide theoretical support for understanding the mechanisms of humidity stratification and optimizing ventilation-drying strategies.
Temperature and humidity within grain bulks are two critical factors affecting the safe storage duration of grains. Investigating the heat and moisture transfer mechanisms during storage, along with the coupled interactions among various in-silo factors, enables better prediction of grain storage conditions and supports high-quality grain preservation. In this study, a paddy grain bulk exhibiting humidity stratification inside a grain silo is selected as the research subjet. Based on multi-physics coupling theory, a comprehensive study is conducted on the heat and moisture transfer processes in the paddy grain bulk. A coupled heat and moisture transfer model is established under mechanical ventilation conditions according to the principles of mass, energy, and momentum conservation. Experimental validation is conducted using a custom-built grain silo test chamber, in which temperature and humidity data are collected during ventilation and compared with simulation results to assess model accuracy. The results show that the maximum temperature deviation between simulated and measured values at various monitoring points is 0.94 °C, while the relative humidity error remains within 2%, demonstrating the model’s high accuracy and adaptability. Building upon existing heat and moisture modeling efforts, this study further deepens the coupling mechanisms and enables dynamic simulation and quantitative analysis of humidity stratification within the grain bulk. These findings provide theoretical support for understanding the mechanisms of humidity stratification and optimizing ventilation-drying strategies.
摘要:
Purpose In order to replace the traditional grain condition measurement and control system to complete the grain condition detection operation inside the grain pile, design a robot that can drill into the inside of the grain pile and realize the grain condition detection operation inside the pile.
In order to replace the traditional grain condition measurement and control system to complete the grain condition detection operation inside the grain pile, design a robot that can drill into the inside of the grain pile and realize the grain condition detection operation inside the pile.
Methods According to the actual operation scenario, the overall structure and drive form of the grain detection robot are determined, and the torque balance equation of the spiral drive wheel in the grain pile is established based on the principle of ground science. Optimize the structural parameters of the spiral drive wheel using RecurDyn-EDEM coupled simulation, take the lift angle, height, number of spiral blades and the taper angle of the outer contour of the spiral drive wheel as the optimization target parameters, and take the speed, axial resistance magnitude, torsional resistance moment and propulsive efficiency as the evaluation indexes, and analyze the influence of different parameters on the motion performance of the spiral drive wheel. A test platform is built to test the torque and displacement of the helical drive wheel, and the difference between the simulated and experimental values under the same experimental conditions is compared to prove the high reliability of the simulation model, and to test the kinematic performance of the food situation detection robot.
According to the actual operation scenario, the overall structure and drive form of the grain detection robot are determined, and the torque balance equation of the spiral drive wheel in the grain pile is established based on the principle of ground science. Optimize the structural parameters of the spiral drive wheel using RecurDyn-EDEM coupled simulation, take the lift angle, height, number of spiral blades and the taper angle of the outer contour of the spiral drive wheel as the optimization target parameters, and take the speed, axial resistance magnitude, torsional resistance moment and propulsive efficiency as the evaluation indexes, and analyze the influence of different parameters on the motion performance of the spiral drive wheel. A test platform is built to test the torque and displacement of the helical drive wheel, and the difference between the simulated and experimental values under the same experimental conditions is compared to prove the high reliability of the simulation model, and to test the kinematic performance of the food situation detection robot.
RESULTS The simulation results show that the kinematic performance of the helical drive wheel is best when the helical lift angle of the helical drive wheel is 35°, the maximum height of the helical blades is 35mm, the taper angle of the outer contour of the helical drive wheel is 20°, and the number of the helical blades is 4 pieces. The kinematic performance test experiment shows that when the rotational speed of the spiral driving wheel is 30r/min, the prototype dives to about 460mm below the grain surface after 32s, with an average dive speed of about 14mm/s and an average slip rate of 78.21%.
The simulation results show that the kinematic performance of the helical drive wheel is best when the helical lift angle of the helical drive wheel is 35°, the maximum height of the helical blades is 35mm, the taper angle of the outer contour of the helical drive wheel is 20°, and the number of the helical blades is 4 pieces. The kinematic performance test experiment shows that when the rotational speed of the spiral driving wheel is 30r/min, the prototype dives to about 460mm below the grain surface after 32s, with an average dive speed of about 14mm/s and an average slip rate of 78.21%.
CONCLUSION The comparison experiment proves the high reliability of the simulation model. The motion performance test experiment shows that the grain detection robot can drill into the internal operation of the grain pile, and subsequently can be equipped with a variety of sensors to complete such operations as temperature and humidity detection, cuttings, turning grain and so on.
The comparison experiment proves the high reliability of the simulation model. The motion performance test experiment shows that the grain detection robot can drill into the internal operation of the grain pile, and subsequently can be equipped with a variety of sensors to complete such operations as temperature and humidity detection, cuttings, turning grain and so on.
摘要:
Olive oil is widely used for its easy availability, biodegradability, and environmental friendliness. It is a good potential candidate for green lubrication performance. However, lack of research on the tribological behavior of sliding contact under high-temperature conditions limits its use in high-temperature lubrication. To gain a deeper comprehension of how olive oil lubricates under high-temperature settings, an equipped friction testing apparatus with temperature regulation capabilities was utilized for a thorough investigation. Testing results show that high-temperature olive oil lubrication can be divided into four stages: start-up lubrication stage, steady lubrication stage, transition lubrication stage, and lubrication failure stage (dry friction). The material wear mechanisms under olive oil lubrication at high temperatures mainly include abrasive wear, adhesive wear, fatigue wear, oxidation wear. The effects of olive oil under high-temperature conditions, including load, speed, and temperature, were further discussed.Its reveals the lubrication mechanism of olive oil under high-temperature sliding contact conditions.
Olive oil is widely used for its easy availability, biodegradability, and environmental friendliness. It is a good potential candidate for green lubrication performance. However, lack of research on the tribological behavior of sliding contact under high-temperature conditions limits its use in high-temperature lubrication. To gain a deeper comprehension of how olive oil lubricates under high-temperature settings, an equipped friction testing apparatus with temperature regulation capabilities was utilized for a thorough investigation. Testing results show that high-temperature olive oil lubrication can be divided into four stages: start-up lubrication stage, steady lubrication stage, transition lubrication stage, and lubrication failure stage (dry friction). The material wear mechanisms under olive oil lubrication at high temperatures mainly include abrasive wear, adhesive wear, fatigue wear, oxidation wear. The effects of olive oil under high-temperature conditions, including load, speed, and temperature, were further discussed.Its reveals the lubrication mechanism of olive oil under high-temperature sliding contact conditions.
摘要:
Grain is the root of the people, and grain storage is a top priority. It is necessary to improve the efficiency of grain storage operations and reduce work intensity, so it is important to develop an automated or even intelligent grain leveling robot for the precise operation of grain silos. In this paper, we propose an area classification method based on target leveling height for the special working mode of truss-type grain leveling robot, simplify the 3D map to a 2D map, reduce the difficulty of path planning, and improve the working efficiency. Based on multi-level path planning and genetic algorithm to achieve the planning of the working path of the grain-leveling robot, it solves the problem of a large number of useless trips under the adoption of full-coverage operation. It saves a lot of time, improves grain-leveling efficiency, reduces energy consumption, optimizes the effect of grain-leveling, and helps realize the precise storage operation of grain silos. The experiment of rough leveling operation was carried out through the grain leveling robot prototype and the simulated experimental warehouse, and the results show that the height difference between the peak of the grain surface and the target leveling height is within 5 cm, which verifies that the path planning method in this paper is feasible, and shows that the grain leveling robot can complete the task of grain leveling and the effect is good.
期刊:
Journal of Vibration Engineering & Technologies,2025年13(3):1-10 ISSN:2523-3920
通讯作者:
Zhang, H
作者机构:
[Song, Shaoyun; Zhang, Heng; Yang, Junsheng] Wuhan Polytech Univ, Sch Mech Engn, Wuhan 430048, Peoples R China.;[Wang, Yue] Beijing Inst Space Mech & Elect, Beijing 100094, Peoples R China.
通讯机构:
[Zhang, H ] W;Wuhan Polytech Univ, Sch Mech Engn, Wuhan 430048, Peoples R China.
关键词:
Vibration isolation;Viscoelastic material;Constrained damping isolator;Impact test;Satellite camera
摘要:
PurposeTo achieve high efficiency of vibration isolation and to conserve the structural stability for the spaceborne satellite camera in the launch phase, design and validation of the whole-spacecraft vibration isolator with quasi-equal strength, high damping and shock protection is presented.MethodsMetal frame structure model of the isolator is established based on equal strength beam theory. The constitutive relation for linear viscoelastic damping material is expressed by five-parameter fractional derivative model. The optimization of constrained damping structure including the damping layer thickness and the number of damping layers is performed by numerical calculation. Finite element analysis and tests for the isolator unit strut are carried out to study the dynamic characteristics of the isolation unit.ResultsSystem vibration tests are performed to verify the performance of the whole isolation platform, which is found that the designed vibration isolation system can effectively restrain the transmission of vibration energy.ConclusionThe study can shed some light on the design of a passive isolator with quasi-equal strength and high damping.
通讯机构:
[Li, JK ] W;Wuhan Polytech Univ, Sch Mech Engn, Wuhan 430023, Peoples R China.
关键词:
Multi-source information fusion;Grain situation analysis;Rice pile characteristics;Space-time law;Evaluation model
摘要:
Grain storage is a complex process, affected by factors such as mold, temperature, humidity, and moisture. The use of multiple sensors to detect changes in rice pile parameters has gained prominence as a means to ensure the accuracy and timeliness of grain condition monitoring. However, the current technology does not effectively utilize data. The assessment criteria primarily rely on grain temperature, and the analysis of grain condition is simplistic. Additionally, it fails to adequately integrate information on temperature, humidity, moisture, gas concentration, and other parameters of the grain pile to form a unified assessment result. To address the isolated and one-sided reaction of various parameters in the grain pile, this thesis conducts research on the storage characteristics of heating, condensation, and mold condition. It combines the information fusion of temperature, humidity, moisture, and CO2 with normal grain conditions, constructs an assessment model based on the classification and identification of grain conditions under gray correlation, and achieves real-time dynamic assessment of the state of the grain pile. The experimental results show that the assessment model based on gray correlation can accurately discriminate between normal and mold conditions, but the accuracy in distinguishing heating and condensation still requires improvement. The overall recognition rate of the four types of grain conditions is 79%, which demonstrates the effectiveness of the model in identifying abnormal grain states.
Grain storage is a complex process, affected by factors such as mold, temperature, humidity, and moisture. The use of multiple sensors to detect changes in rice pile parameters has gained prominence as a means to ensure the accuracy and timeliness of grain condition monitoring. However, the current technology does not effectively utilize data. The assessment criteria primarily rely on grain temperature, and the analysis of grain condition is simplistic. Additionally, it fails to adequately integrate information on temperature, humidity, moisture, gas concentration, and other parameters of the grain pile to form a unified assessment result. To address the isolated and one-sided reaction of various parameters in the grain pile, this thesis conducts research on the storage characteristics of heating, condensation, and mold condition. It combines the information fusion of temperature, humidity, moisture, and CO2 with normal grain conditions, constructs an assessment model based on the classification and identification of grain conditions under gray correlation, and achieves real-time dynamic assessment of the state of the grain pile. The experimental results show that the assessment model based on gray correlation can accurately discriminate between normal and mold conditions, but the accuracy in distinguishing heating and condensation still requires improvement. The overall recognition rate of the four types of grain conditions is 79%, which demonstrates the effectiveness of the model in identifying abnormal grain states.
摘要:
Following the global outbreak of the new coronavirus, all universities and colleges have been working hard to ensure that their students have the right to learn, and the combination of online and offline teaching mode has become the current educational norm. However, the traditional offline classroom teaching evaluation monitoring system is not suitable for the current requirements of blended teaching. Based on hierarchical analysis and fuzzy comprehensive evaluation algorithm, we explore the teaching evaluation monitoring system with multiple dimensions such as teaching quality monitoring, teaching quality evaluation, teaching feedback and improvement adapted to the hybrid teaching mode, and realise the web visualisation interface of teaching evaluation monitoring system with the help of computer technology. This new online and offline hybrid teaching evaluation monitoring system will provide support and guarantee to promote the hybrid teaching reform and improve teaching quality.
摘要:
Castor oil has been widely used in various fields due to its properties, leading to large attention for its extraction mechanism. To research the castor oil extraction mechanism during pressing, a self-developed uniaxial compression device combined with an in situ observation is established. The effects of pressure, loading speed, and creep time are investigated, and a finite element model coupling with multi-physics is established for castor oil pressing extraction, verified by the seed cake experimental compression strain matching with numerical simulation under the same condition. Simulation results indicated that the pressing oil extraction process can be divided into two stages, Darcy's speed shows the first sharp decreasing stage and the second gradual increasing stage during porosity and pressure interaction. In the first stage, porosity is dominant on Darcy's speed. With porosity decreasing, the pressure effect on Darcy's speed exceeds porosity in the second stage. With seed thickness increasing, Darcy's speed first increases and then decreases. With loading speed increasing, Darcy's speed increases. Darcy's speed decreases constantly with creep time increasing. This study can provide basic theoretical and practical guidance for oil extraction.
通讯机构:
[Yang, L ] W;Wuhan Polytech Univ, Coll Mech Engn, Wuhan 430048, Hubei, Peoples R China.
关键词:
brown rice;DOM prediction;features extraction;machine learning;SHAP interpretation
摘要:
Brown rice over-milling causes high economic and nutrient loss. The rice degree of milling (DOM) detection and prediction remain a challenge for moderate processing. In this study, a self-established grain image acquisition platform was built. Degree of bran layer remaining (DOR) datasets is established with image capturing and processing (grain color, texture, and shape features extraction). The mapping relationship between DOR and the DOM is in-depth analyzed. Rice grain DOR typical machine learning and deep learning prediction models are established. The results indicate that the optimized Catboost model can be established with cross-validation and grid search method, with the best accuracy improving from 84.28% to 91.24%, achieving precision 91.31%, recall 90.89%, and F1-score 91.07%. Shapley additive explanations analysis indicates that color, texture, and shape feature affect Catboost prediction accuracy, the feature importance: color>texture>shape. The YCbCr-Cb_ske and GLCM-Contrast features make the most significant contribution to rice milling quality prediction. The feature importance provides theoretical and practical guidancefor grain DOM prediction model. PRACTICAL APPLICATION: Rice milling degree prediction and detection are valuable for rice milling process in practical application. In this paper, image processing and machine learning methods provide an automated, nondestructive, and cost-effective way to predict the quality of rice. The study may serve as a valuable reference for improving rice milling methods, retaining rice nutrition, and reducing broken rice yield.
通讯机构:
[Yang, L ] W;Wuhan Polytech Univ, Coll Mech Engn, Wuhan 430048, Hubei, Peoples R China.
关键词:
Brown rice;Bran layer;Micro-structure;Moderate processing
摘要:
Moderate processing can improve the edible rice grain quality and nutrition. The grain structural-removal behavior was researched based on the macro and micro-structure analysis. Grain bran layer 3D profiling combined with iodine solution staining is applied for geometrical-structural analysis. Results show that rice grain can be divided into five structural region based on bran layer removal capacity, lateral > ventral > ventral groove > dorsal > dorsal groove. The relationship between grain geometric parameters and collision possibility is in-depth analyzed, results indicated large grain surface curvature leads to grain surface layer hard removal capacity. The region's bran layer thickness distribution affects its removal behavior and obey its removal capacity. The regional bran layer thickness order: dorsal(59.56 μm) > dorsal groove(50.62 μm) > ventral(43.91 μm) > ventral groove(42.83 μm) > lateral(37.08 μm). The bran layer micro-morphology impacts removal behavior, dorsal region with the groove structure, the bottom surface layer in grain groove structure can be removed when groove structure is damaged. The ventral groove depth is less than dorsal groove, showing better removal ability. The bran layer color in L*A*B*space shows strong correlation with remaining layer thickness, reflecting grain milling degree. Combined effects of grain geometry-parameters, bran layer thickness and micro-structure lead the final bran layer removal behavior. This study provides theoretical and practical basis for grain moderate processing.
Moderate processing can improve the edible rice grain quality and nutrition. The grain structural-removal behavior was researched based on the macro and micro-structure analysis. Grain bran layer 3D profiling combined with iodine solution staining is applied for geometrical-structural analysis. Results show that rice grain can be divided into five structural region based on bran layer removal capacity, lateral > ventral > ventral groove > dorsal > dorsal groove. The relationship between grain geometric parameters and collision possibility is in-depth analyzed, results indicated large grain surface curvature leads to grain surface layer hard removal capacity. The region's bran layer thickness distribution affects its removal behavior and obey its removal capacity. The regional bran layer thickness order: dorsal(59.56 μm) > dorsal groove(50.62 μm) > ventral(43.91 μm) > ventral groove(42.83 μm) > lateral(37.08 μm). The bran layer micro-morphology impacts removal behavior, dorsal region with the groove structure, the bottom surface layer in grain groove structure can be removed when groove structure is damaged. The ventral groove depth is less than dorsal groove, showing better removal ability. The bran layer color in L*A*B*space shows strong correlation with remaining layer thickness, reflecting grain milling degree. Combined effects of grain geometry-parameters, bran layer thickness and micro-structure lead the final bran layer removal behavior. This study provides theoretical and practical basis for grain moderate processing.
摘要:
Apples have been constantly damaged in collecting, transporting, and processing, leading research focus on apples' mechanical-structural damage behavior. To research apples' mechanical-structural damage behavior during collision, a dropping collision damage testing device was self-established, with PLC control, data acquisition-processing, in situ high-speed observation. The effect of impact material, drop height, impact orientation on apple deformation and bruise area was investigated with self-established device, considering three typical kinds of apples. The results indicated that apple dropping collision can be divided into two stages: dropping down contact deformation stage and recovering contact deformation stage. Three kinds of apples demonstrate the largest deformation and bruise area when the impact material is steel and acrylic plate. The deformation is similar when apples collide with soil and foam, apples have no bruise area when the impact material is foam. The correlation between apple deformation, bruising area, and drop height was established, reflecting the relationship between drop height and apples' mechanical-structural damage behavior. Yellow Marshal apple deformation is the largest compared to other two kinds of apples under the same collision condition. Red Fuji apple bruise area is the largest compared to other two kinds of apples. The largest bruise area of Yellow Marshal apple and Guoguang apple are in apple transverse, and Red Fuji apple is in apple top. The study can provide basic theoretical and practical guidance for apples postharvest work.