Biosystems Engineering最新文献_第2页

An application oriented all-round intelligent weeding machine with enhanced YOLOv5 以应用为导向的全方位智能除草机，配备增强型 YOLOv5

IF 4.4 1区农林科学

Biosystems Engineering Pub Date : 2024-11-17 DOI: 10.1016/j.biosystemseng.2024.11.009

Meiqi Xiang, Xiaomei Gao, Gang Wang, Jiangtao Qi, Minghao Qu, Zhongyang Ma, Xuegeng Chen, Zihao Zhou, Kexin Song

{"title":"An application oriented all-round intelligent weeding machine with enhanced YOLOv5","authors":"Meiqi Xiang, Xiaomei Gao, Gang Wang, Jiangtao Qi, Minghao Qu, Zhongyang Ma, Xuegeng Chen, Zihao Zhou, Kexin Song","doi":"10.1016/j.biosystemseng.2024.11.009","DOIUrl":"10.1016/j.biosystemseng.2024.11.009","url":null,"abstract":"<div><div>Nobody would contest that physical weed removal methods offer numerous advantages over biochemical alternatives. Within the domain of intelligent mechanical weed control, comprehensive research targeting the entire intelligent weeding machine system remains relatively scarce. To expedite the practical application of intelligent weeding machines, this study explored an enhanced YOLOv5 model with one colour constancy module, which aimed at achieving higher accuracy in crop seedling detection. An innovative \"separating and closing\" strategy, which allows the machine to precisely avoid crop seedlings while effectively weeding the areas between crop seedlings was employed to facilitate intra-row weeding. By integrating this strategy with a comprehensive design of the mobile platform, inter-row weeding actuators, and harmonious control of these key components, this research successfully developed an intelligent weeding machine capable of simultaneously performing intra-row and inter-row (all-round) weeding. Compared with previous studies, this study put the emphases on complex farm lighting conditions, both inter-row and intra-row weeding functions, and weed regrowth. Field experiments conducted in lettuce (<em>Lactuca sativa</em> var. <em>ramosa</em> Hort.) fields at four different locations on three separate dates demonstrated that this intelligent weeding machine achieved average weeding rates, crop seedling damage rates, and regrowth rates of 96.87%, 1.19%, and 0.34%, respectively. The ability to perform all-round weeding simultaneously is a significant advance in mechanical weeding control. The design and methodology employed in this study have broad implications for advancing the field of precision agriculture and addressing the growing demand for sustainable farming practices.</div></div>","PeriodicalId":9173,"journal":{"name":"Biosystems Engineering","volume":"248 ","pages":"Pages 269-282"},"PeriodicalIF":4.4,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Characterising vibration patterns of winter jujube trees to optimise automated fruit harvesting 表征冬枣树的振动模式，优化果实的自动采摘

IF 4.4 1区农林科学

Biosystems Engineering Pub Date : 2024-11-16 DOI: 10.1016/j.biosystemseng.2024.11.004

Zhouzhou Zheng , Yaohua Hu , Jianxin Dong , Pengfei Zhao , Yixue Liu , Xintong Jiang , Yichen Qiao , Shangpeng Sun , Yuxiang Huang

{"title":"Characterising vibration patterns of winter jujube trees to optimise automated fruit harvesting","authors":"Zhouzhou Zheng , Yaohua Hu , Jianxin Dong , Pengfei Zhao , Yixue Liu , Xintong Jiang , Yichen Qiao , Shangpeng Sun , Yuxiang Huang","doi":"10.1016/j.biosystemseng.2024.11.004","DOIUrl":"10.1016/j.biosystemseng.2024.11.004","url":null,"abstract":"<div><div>Understanding jujube tree dynamic characteristics is crucial for the design and invention of a catch-and-shake machine for fruit harvesting. Currently, the study of vibration characteristics based on the finite element method is the mainstream method for different types of fruit trees. However, limited by the lack of an accurate 3D tree model, there are still gaps between existing simulation analysis and actual tests to explore vibration characteristics. Specifically, the vibration mechanism of winter jujube trees is still unclear in jujube orchards. To address the issue, a multi-view 3D reconstruction technique is employed to acquire precise 3D tree models for simulation analysis. The obtained results from experiments indicate that the determination coefficient <em>R</em><sup>2</sup> of the trunks and branches diameter are 0.96 and 0.91 between reconstructed and actual measurement results. Subsequently, material properties of jujube tree are measured to conduct model analysis and harmonic response analysis to find the optimal frequency range (10–20 Hz) in which a considerable vibration response can be obtained at low vibration energies. Moreover, transient analysis and test experiments are conducted to explore the energy transfer properties under different vibration frequency. Results showed that the acceleration response gradually increased from the bottom to the top of the branch on most branches at non-resonant frequencies. The proposed method can provide informative insights on the design of high-efficiency and low-energy jujube catch-and-shake harvesters.</div></div>","PeriodicalId":9173,"journal":{"name":"Biosystems Engineering","volume":"248 ","pages":"Pages 255-268"},"PeriodicalIF":4.4,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

UAV multispectral remote sensing for agriculture: A comparative study of radiometric correction methods under varying illumination conditions 无人机多光谱农业遥感：不同光照条件下辐射校正方法的比较研究

IF 4.4 1区农林科学

Biosystems Engineering Pub Date : 2024-11-15 DOI: 10.1016/j.biosystemseng.2024.11.005

Yuxiang Wang , Gert Kootstra , Zengling Yang , Haris Ahmad Khan

{"title":"UAV multispectral remote sensing for agriculture: A comparative study of radiometric correction methods under varying illumination conditions","authors":"Yuxiang Wang , Gert Kootstra , Zengling Yang , Haris Ahmad Khan","doi":"10.1016/j.biosystemseng.2024.11.005","DOIUrl":"10.1016/j.biosystemseng.2024.11.005","url":null,"abstract":"<div><div>Unmanned aerial vehicles (UAVs) equipped with multispectral cameras have been widely used in precision agriculture. However, a notable challenge is the variation in ambient illumination, which affects the accuracy and reliability of UAV-based spectral-data acquisition. In this study, the aim is to evaluate and enhance the performance of existing radiometric correction techniques under varying illumination conditions, primarily concerning radiometric accuracy and homogeneity. Seven methods including three conventional methods and four new methods were employed for correcting the MicaSense Altum multispectral system which equips with a downwelling light sensor (DLS). Two specific strategies were adopted: (1) capturing reference panels at UAV flying altitudes, and (2) strategically placing multiple sets of reference panels throughout the study area. The result shows that calibrating images one time, for instance, the empirical line method (ELM), is seriously affected by the variable illumination. The commercial solution that using the DLS helps improve the uniformity of orthomosaics but lower its radiometric accuracy. Optimising the use of the DLS by capturing panels at the UAV's flight altitude can greatly improve accuracy. Additionally, when the DLS is unavailable, strategically placing multiple reference panels across the field and correcting calibration parameters for each image can effectively help mitigate the impact of varying illumination on generated reflectance orthomosaics. In conclusion, selecting suitable radiometric correction methods is crucial for UAV multi-spectral data collection when facing variable illumination conditions.</div></div>","PeriodicalId":9173,"journal":{"name":"Biosystems Engineering","volume":"248 ","pages":"Pages 240-254"},"PeriodicalIF":4.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimising maize threshing process with temporal proximity soft actor-critic deep reinforcement learning algorithm 利用时间临近软行为批判深度强化学习算法优化玉米脱粒过程

IF 4.4 1区农林科学

Biosystems Engineering Pub Date : 2024-11-05 DOI: 10.1016/j.biosystemseng.2024.11.001

Qiang Zhang , Xuwen Fang , Xiaodi Gao , Jinsong Zhang , Xuelin Zhao , Lulu Yu , Chunsheng Yu , Deyi Zhou , Haigen Zhou , Li Zhang , Xinling Wu

{"title":"Optimising maize threshing process with temporal proximity soft actor-critic deep reinforcement learning algorithm","authors":"Qiang Zhang , Xuwen Fang , Xiaodi Gao , Jinsong Zhang , Xuelin Zhao , Lulu Yu , Chunsheng Yu , Deyi Zhou , Haigen Zhou , Li Zhang , Xinling Wu","doi":"10.1016/j.biosystemseng.2024.11.001","DOIUrl":"10.1016/j.biosystemseng.2024.11.001","url":null,"abstract":"<div><div>Maize threshing is a crucial process in grain production, and optimising it is essential for reducing post-harvest losses. This study proposes a model-based temporal proximity soft actor-critic (TP-SAC) algorithm to optimise the maize threshing process in the threshing drum. The proposed approach employs an LSTM model as a real-time predictor of threshing quality, achieving an R<sup>2</sup> of 97.17% and 98.43% for damage and unthreshed rates on the validation set. In actual threshing experiments, the LSTM model demonstrates an average error of 5.45% and 3.83% for damage and unthreshed rates. The LSTM model is integrated with the TP-SAC algorithm, acting as the environment with which the TP-SAC interacts, enabling efficient training with limited real-world data. The TP-SAC algorithm addresses the temporal correlation in the threshing process by incorporating temporal proximity sampling into the SAC algorithm's experience replay mechanism. TP-SAC outperforms the standard SAC algorithm in the simulated environment, demonstrating better sample efficiency and faster convergence. When deployed in actual threshing operations, the TP-SAC algorithm reduces the damage rate by an average of 0.91% across different feed rates compared to constant control. The proposed TP-SAC algorithm offers a novel and practical approach to optimising the maize threshing process, enhancing threshing quality.</div></div>","PeriodicalId":9173,"journal":{"name":"Biosystems Engineering","volume":"248 ","pages":"Pages 229-239"},"PeriodicalIF":4.4,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of polyphenol-rich extracts and compounds on methane and ammonia emissions from pig slurry during 28-day incubation 富含多酚的提取物和化合物对 28 天培养期间猪粪中甲烷和氨排放的影响

IF 4.4 1区农林科学

Biosystems Engineering Pub Date : 2024-11-05 DOI: 10.1016/j.biosystemseng.2024.11.002

Ali Heidarzadeh Vazifehkhoran , Johanna Pedersen , Lise Bonne Guldberg , Simon Svane , Henrik Karring , Anders Feilberg , Michael Jørgen Hansen

{"title":"Effects of polyphenol-rich extracts and compounds on methane and ammonia emissions from pig slurry during 28-day incubation","authors":"Ali Heidarzadeh Vazifehkhoran , Johanna Pedersen , Lise Bonne Guldberg , Simon Svane , Henrik Karring , Anders Feilberg , Michael Jørgen Hansen","doi":"10.1016/j.biosystemseng.2024.11.002","DOIUrl":"10.1016/j.biosystemseng.2024.11.002","url":null,"abstract":"<div><div>Animal manure in livestock production facilities is a major source of methane (CH<sub>4</sub>) and ammonia (NH<sub>3</sub>) emissions from agriculture. In this study, we investigated different polyphenol-rich extracts and chemicals including commercial chestnut tannin (CT), shea meal extract (SME) and lignosulfonic acid (LSA) in combination with 1 mM of urease inhibitors acetohydroxamic acid (AHA) and/or sodium fluoride (NaF) to mitigate CH<sub>4</sub> and NH<sub>3</sub> in an <em>in-vitro</em> setup with 0.5 L slurry reactors mimicking slurry pits in livestock facilities. Daily addition of pig feces and urine along with additives were conducted for 28 days at room temperature, while CH<sub>4</sub> and NH<sub>3</sub> emissions were monitored by cavity ring-down spectroscopy (CRDS) continuously. SME and SME + NaF added to slurry reduced CH<sub>4</sub> emission by 72% and 88%, and NH<sub>3</sub> emission by 45% and 52%, respectively. CT + NaF at the CT concentration of 2.6, 4.25 and 8.5 mg mL<sup>−1</sup>, resulted in 48–55%, 70–72% and 81% reduction in CH<sub>4</sub> emission, and 17–29%, 40–49% and 49% reduction in NH<sub>3</sub> emission, respectively. Emission reduction based on the dosage of CT revealed that the relationship between dosage and emission reduction is not linear, therefore the reduction efficiency was calculated by emission reduction divided by concentration. CH<sub>4</sub> reduction efficiency at the CT concentration of 2.6, 4.25 and 8.5 mg mL<sup>−1</sup> were 18–21, 16–17 and 10 % (mg mL<sup>−1</sup>)<sup>−1</sup>. Therefore, the optimum dosage of CT was 4.25 mg mL<sup>−1</sup>. In conclusion, addition of CT and SME along with NaF resulted in significant reductions of both CH<sub>4</sub> and NH<sub>3</sub> emissions, while supplementation of LSA and AHA to CT + NaF did not enhance the mitigation effect.</div></div>","PeriodicalId":9173,"journal":{"name":"Biosystems Engineering","volume":"248 ","pages":"Pages 218-228"},"PeriodicalIF":4.4,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Scaled experimental study of a ventilation system featuring partition jet and pit exhaust 分区喷气和坑式排气通风系统的比例实验研究

IF 4.4 1区农林科学

Biosystems Engineering Pub Date : 2024-11-02 DOI: 10.1016/j.biosystemseng.2024.10.010

Qizhi Yang , Xi Bai , Guoqiang Zhang , Li Rong , Yao Tao , Jiyuan Tu , Jinyong Wang , Zhiru Hu , Jie Chai , Yong Wang

{"title":"Scaled experimental study of a ventilation system featuring partition jet and pit exhaust","authors":"Qizhi Yang , Xi Bai , Guoqiang Zhang , Li Rong , Yao Tao , Jiyuan Tu , Jinyong Wang , Zhiru Hu , Jie Chai , Yong Wang","doi":"10.1016/j.biosystemseng.2024.10.010","DOIUrl":"10.1016/j.biosystemseng.2024.10.010","url":null,"abstract":"<div><div>In the context of current intensive livestock farming development, we present a novel energy-efficient ventilation method, named as the partition jet and pit exhaust (PJPE) system, for multi-story pig facilities. The objective is to overcome the limitations of traditional ventilation methods, e.g., mixing ventilation sidewall air supply or tunnel ventilation, in managing heat stress and air quality. Isothermal and non-isothermal experiments were conducted in a 1:2.5 scaled pig pen model to study the airflow distribution characteristics and ventilation effectiveness of the PJPE system. The results demonstrate that the PJPE system enables rapid delivery of fresh air to the animal-occupied zone (AOZ). With the Archimedes numbers (Ar) of supply air ranging between 0.0025 and 0.0052, the jet maintains low air temperatures near the pig's back. Compared to traditional pig house ventilation methods, the PJPE demonstrates better heat removal efficiency (HRE), with an average HRE of 1.20. Additionally, the PJPE effectively inhibits the upward diffusion of ammonia from the slurry pit. These findings indicate that the PJPE system presents a viable, energy-efficient alternative for environmental control in high-density pig housing, highlighting its potential for advancing animal welfare and productivity in intensive livestock farming.</div></div>","PeriodicalId":9173,"journal":{"name":"Biosystems Engineering","volume":"248 ","pages":"Pages 206-217"},"PeriodicalIF":4.4,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simulation and experimental study on frictional wear of plough blades in soil cultivation process based on the Archard model 基于 Archard 模型的土壤耕作过程中犁刃摩擦磨损模拟与实验研究

IF 4.4 1区农林科学

Biosystems Engineering Pub Date : 2024-11-01 DOI: 10.1016/j.biosystemseng.2024.10.009

Peng Zhang , Xiongye Zhang , Xue Hu , Lixin Zhang , Xuebin Shi , Zhigang Li

{"title":"Simulation and experimental study on frictional wear of plough blades in soil cultivation process based on the Archard model","authors":"Peng Zhang , Xiongye Zhang , Xue Hu , Lixin Zhang , Xuebin Shi , Zhigang Li","doi":"10.1016/j.biosystemseng.2024.10.009","DOIUrl":"10.1016/j.biosystemseng.2024.10.009","url":null,"abstract":"<div><div>Plough blades are widely used for land preparation tasks such as rotary tillage and trenching in small farmlands. This paper, using the finite element method, establishes a dynamic simulation model for plough blade cutting through soil. Utilising simulation and experimental data, the study inversely determined a constant value of <em>K</em> = 1.71 × 10<sup>−5</sup> for the wear formula and developed an Archard wear mathematical model applicable to predicting plough blade wear during soil cutting. Subsequently, a Python script was developed for extracting data during the plough blade cutting process. The UMESHMOTION subroutine, combined with the ALE grid remeshing method, was then employed to simulate the wear morphology of the plough blade tip. A comprehensive numerical analysis of wear is conducted over time intervals of 2 h, 3.5 h, 5 h, and 6 h. The results indicated that the maximum wear occurred at the junction between the rear blade surface and the plough blade tip, with corresponding maximum wear amounts of 1.887 mm, 2.750 mm, 3.766 mm, and 4.359 mm. Comparison with actual wear conditions during the operation of a micro-tiller suggests that, within the same wear stage of the blade, the proposed wear numerical analysis method effectively simulated the wear amount during plough blade soil cutting. Furthermore, a comparison of wear amounts under different operational parameters showed that an increase in forward speed led to wear amount increments of 26.62 % and 35.23 %, while an increase in rotational speed resulted in wear amount increments of 17.77 % and 43.88 %. Both factors significantly impact plough blade wear.</div></div>","PeriodicalId":9173,"journal":{"name":"Biosystems Engineering","volume":"248 ","pages":"Pages 190-205"},"PeriodicalIF":4.4,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Harvest motion planning for mango picking robot based on improved RRT-Connect 基于改进型 RRT-Connect 的芒果采摘机器人收获运动规划

IF 4.4 1区农林科学

Biosystems Engineering Pub Date : 2024-10-29 DOI: 10.1016/j.biosystemseng.2024.10.008

Bin Zhang , Chenghai Yin , Yuxing Fu , Yuyang Xia , Wei Fu

{"title":"Harvest motion planning for mango picking robot based on improved RRT-Connect","authors":"Bin Zhang , Chenghai Yin , Yuxing Fu , Yuyang Xia , Wei Fu","doi":"10.1016/j.biosystemseng.2024.10.008","DOIUrl":"10.1016/j.biosystemseng.2024.10.008","url":null,"abstract":"<div><div>Aiming at the problems of long motion path planning time and low picking efficiency of picking robots in unstructured orchard environments, a heuristic dynamic Rapidly-exploring Random Tree Connect motion planning algorithm (HDRRT-Connect) for picking robots for fast mango harvesting path planning was proposed in this study. The algorithm was obtained by introducing adaptive target gravitation strategy and heuristic dynamic step strategy based on RRT-Connect algorithm. It adjusts the step-size according to the information of the orchard environment as well as the path searching situation, so as to avoid falling into the local optimum of the path. The prototype based on the algorithm was used to carry out picking experiments in the natural orchard environment. The prototype picking test under the natural environment of the orchard is carried out, and the test results showed that the average path cost of the HDRRT-Connect algorithm was 95.7739, the average planning time was 0.448 s, and the success rate was 90%. Compared with the RRT, RRT-Connect and Probabilistic Roadmaps (PRM) algorithms, the HDRRT-Connect planning speed was improved by 95%, 24% and 59%, respectively, and the path cost was reduced by 35%, 13% and 18%, respectively. The results of the experiment verified the feasibility and efficiency of the improved algorithm. The HDRRT-Connect algorithm proposed in this study could effectively shorten the planning time, reduce the search path cost and improve the planning success rate. The research provides technical support for the fast-harvesting operation of mango picking robot.</div></div>","PeriodicalId":9173,"journal":{"name":"Biosystems Engineering","volume":"248 ","pages":"Pages 177-189"},"PeriodicalIF":4.4,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142539423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhancing hydraulic efficiency in jet impingement sprinklers: Comparative analysis of aperture ratios compared with non-impingement sprinklers 提高喷射冲击式洒水器的水力效率：孔径比与非撞击式喷洒器的比较分析

IF 4.4 1区农林科学

Biosystems Engineering Pub Date : 2024-10-28 DOI: 10.1016/j.biosystemseng.2024.10.004

Zixin Wang , Yue Jiang , Hong Li , Lisha Wang

{"title":"Enhancing hydraulic efficiency in jet impingement sprinklers: Comparative analysis of aperture ratios compared with non-impingement sprinklers","authors":"Zixin Wang , Yue Jiang , Hong Li , Lisha Wang","doi":"10.1016/j.biosystemseng.2024.10.004","DOIUrl":"10.1016/j.biosystemseng.2024.10.004","url":null,"abstract":"<div><div>A jet impingement sprinkler was designed based on asymmetric collision between the primary and secondary jets to replace traditional rotating sprinklers that require additional water distribution devices to provide suitable water distribution at low pressures. The study focuses on the ratio of apertures between primary and secondary nozzles, deriving a theoretical relationship based on jet momentum. The factors contributing to the variation in hydraulic performance between jet-impingement and non-impinging sprinklers are elucidated by combining hydraulic performance experiments with experiments using high-speed photography (HSP). The results show that the developed jet impingement sprinkler achieved a smoother water distribution trend. The wetted radius and Christiansen's uniformity coefficient of the jet impingement sprinkler were evaluated using the Criteria Importance via the Intercriteria Correlation (CRITIC) method. A comparison of the average scores shows that an aperture ratio of 1.66 performs best under full pressure. By contrast, an aperture ratio of 1.33 exhibited superior performance at low pressure. Jet deflection angle and jet breakup length were obtained through HSP experiments. The relative error between the measured and theoretical jet deflection angles was less than 5%, demonstrating the reliability of the proposed theoretical calculation method. A non-linear curve was used to establish the relationship among the aperture ratio, diameter of the primary nozzle exit, jet breakup length, average measured jet deflection angle, working pressure, and wetted radius. The relative error between the calculated and measured values was within 4%, indicating the suitability of the new formula for calculating the wetted radius of jet impingement sprinklers.</div></div>","PeriodicalId":9173,"journal":{"name":"Biosystems Engineering","volume":"248 ","pages":"Pages 162-176"},"PeriodicalIF":4.4,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142530818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Verifying the reliability of CFD domain decomposition technique on modelling the airflow field inside a naturally ventilated cattle barn 验证 CFD 域分解技术对自然通风牛舍内气流场建模的可靠性

IF 4.4 1区农林科学

Biosystems Engineering Pub Date : 2024-10-24 DOI: 10.1016/j.biosystemseng.2024.10.001

Guoxing Chen, Guoqiang Zhang, Li Rong

{"title":"Verifying the reliability of CFD domain decomposition technique on modelling the airflow field inside a naturally ventilated cattle barn","authors":"Guoxing Chen, Guoqiang Zhang, Li Rong","doi":"10.1016/j.biosystemseng.2024.10.001","DOIUrl":"10.1016/j.biosystemseng.2024.10.001","url":null,"abstract":"<div><div>Conventionally, the airflow fields outside and inside the naturally ventilated livestock buildings are modelled simultaneously in one computational domain using CFD (Computational Fluid Dynamics). The presence of surrounding buildings, indoor facilities and animals for large scale cattle barns make the required computational power extremely high and even unfordable to achieve simulation results with reasonable accuracy. The Domain Decomposition Technique (DDT), dividing simulations into two separate steps, is an alternative CFD framework to provide sufficient accuracy with affordable computations at each step. The objective of this study was to verify the reliability of DDT on modelling the airflow fields inside a naturally ventilated cattle barn (NVCB) by employing wind tunnel measurements. The exterior airflow fields around the targeted NVCB, which was opened with varying opening ratios, were first simulated to obtain the airflow boundary conditions at sidewall openings by applying exterior wind conditions at the inlet of the computational domain. The interior airflow of the targeted NVCB, were secondly simulated by applying the achieved airflow boundary conditions at sidewall openings from the first step simulation. The interior airflow fields obtained by DDT were in good agreement with wind tunnel measurements. This indicates that DDT can provide an alternative for CFD application in large-scale NVCB with presence of surrounding buildings, indoor facilities and animals, though these had not been considered in this study.</div></div>","PeriodicalId":9173,"journal":{"name":"Biosystems Engineering","volume":"248 ","pages":"Pages 156-161"},"PeriodicalIF":4.4,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142530819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0