Simulation of the Impact of the Plough Body Parameters, Soil Properties and Working Modes on the Ploughing Resistance

Non

Parameter Optimization and Test of High-Speed Plough Based on Coupling EDEM and Recurdyn

Depress moldboard plow soil adhesion is gaining relevance in agricultural production due to its rising profitability for producers and its contribution to reducing environmental impacts. This study aimed at the effects of the different structural forms with moldboard plow soil adhesion on adhesion under the joint simulation system. The experiment was conducted at Qianjin in the village of Qianjin, municipality of Daqing, Heilongjiang, China. Using EDEM and Recurdyn to simulate the selected parameters and operating conditions, determine the optimal combination, the field test and simulation comparison verification, the association between. The optimized plough body structure resulted in a 10.86% decrease in the soil adhesion compared to the control, providing a viable alternative for moldboard plow soil adhesion

Analysis of Soil Tillage by Ploughs and Optimisation of Their Aggregation

The mechanical and technological aspects of the impact of ploughing upon the soil fertility have been analysed, as well as the frequency of its crumbling and restoration of the strength of the structure in the arable horizon under the current conditions of agricultural farming. So, a decision on the need for ploughing with a mouldboard plough is not taken every year, but when the soil structure coefficient of the upper layer (8-10 cm) is less than 0.67. A rational of use of mouldboard ploughs with coulters (or application of double-depth ploughs) is substantiated. Scientifically-grounded recommendations for the aggregation of the ploughing machine-andtractor aggregates have been presented. Reduction in the energy costs of ploughing can be ensured by introducing a correct system of aggregating the ploughing tools with energy resources

Theoretical and experimental analysis of the soil pressure and wear distribution on plough

Soil engaging tools are subjected to durability problems due to particularly severe wear. During ploughing work wear is generated by the interaction between tillage tool and soil. There are several wear modes on tillage tools, but the predominant cause of material loss is due to the abrasive action of soil particles. Wear rate is strongly affected by soil-tool pressure distribution and it compromises plough performances during its life cycle. The aim of this PhD thesis is the development of a test methodology able to measure and evaluate the pressure distribution on a working plough body using tactile sensors. Field tests were performed with a 4 furrows reversible plough by Gruppo Nardi attached to a New Holland T7.260 tractor and tested at different soils, speeds and ploughing depths. Tractor speed and the horizontal force at the hitch points of the plough were measured. The pressure mean value is influenced both by speed and depth, but each part of the plough has its own characteristic behaviour. The pressure signals demonstrated to be spiky, in fact the pressure mean value was lower than 1% of the maximum value for up to 92% of the ploughed distance. Moreover, spike patterns are markedly affected by the speed especially in terms of the number of spikes and their distribution. The methodology and the results introduced in this PhD thesis will be useful for the validation of mathematical models to simulate the ploughing process, reducing the time required for the engineering design process of optimized ploughs. A possible future development of this research activity is the design of accelerated tests in order to permit a fast validation of plough bodies

Abrasive wear testing of steels in soil

Bibliography: pages 133-136.A survey has been made of the quality and type of materials used for tillage tools in South Africa. Conclusions have been drawn regarding the inadequacy of the manufacturing processes used and the resultant quality of the tool material. A rig has been designed for the abrasion testing of materials in soil. The reproducibility of the method has been shown to be high and an evaluation has been made of the relative wear resistance of a series of ·heat treated steels. A medium carbon boron steel has been shown to have great promise as a tillage tool material because of its high wear resistance and toughness. The deformed surface layers and the mechanisms of wear of steels subjected to field and laboratory abrasive testing has been examined. The removal of material through predominantly ploughing or cutting mechanisms has been shown to be dependent on the heat treatment and composition of the steels together with the nature of the abrasive. White surface layers have been observed to form on medium and high carbon steels subjected to soil abrasion. Suggestions have been advanced for their formation. Attempts have been made to assess the transferability of data between field and laboratory testing

The influence of steel microstructure on abrasive wear in soils

Bibliography: pages 96-104.A hypoeutectoid steel has been heat treated to produce a range of different hardnesses and microstructures. A simulative field test rig has been employed to determine the relationship between microstructural parameters, material properties and soil constitution. Attempts have been made to correlate the ranking order for the wear resistance of similar treated steels in field and laboratory tests. It has been established that wear resistance is a function of soil constitution, steel carbide morphology and hardness. Explanations have been advanced for the differences in the wear resistance of similar steels in different soils based on the mechanism of material removal. Recommendations have been made regarding the selection of steel microstructure for varying soil conditions

Soil workability as a basis for advice on tillage activities

In the tropical area of Mexico, when and how to carry out tillage is a qualitative decision. There is no quantified information about the interaction between a chosen process of cultivation, soil type and weather, which dictate the tool and power requirements. Waste of energy and soil degradation by erosion and compaction, and lack of timeliness are recognized problems caused by inadequate tillage management in the tropical area of Mexico.In this thesis, the workable range of soils was quantified in the field, and the limits of that range, represented in the laboratory by tests to soil samples. This information is the basic part of a soil workability based procedure which is developed as a decision support tool for selecting specific tillage practices. The methodology was conceived for application in the tropical area of Mexico. For this reason a description of the area under study in relation to the present agricultural production system, including tillage related problems, was presented in Chapter 2 .In Chapter 3, The field and the laboratory studies to quantify the workable range of soils in the area, were treated. The methodology and results from those studies were presented and discussed, considering the technological result of the tillage operation and the input of energy at a range of soil moisture contents. Empirical relationships between initial moisture content and the technological result of tillage showed that results from Loam and Clay soils changed from optimum to sub-optimum at soil water potentials that rather coincide with the plastic limit in relatively moist soil. As soil was drying out , the implement result changed from optimum to sub-optimum at soil water potentials well below to that for the shrinkage limit, so the actual field work was smaller than the theoretical friable range of the soils. The minimum input of specific energy to obtain optimum results was close to the soil water potential, where results changed to sub-optimum as the soils where drying out. Observations in a Sandy soil indicate that required technological result is attained at almost any moisture content.The thresholds that delimit the optimum and sub-optimum results in the field are represented by means of laboratory tests, air permeability test (for a wet limit) and a Drop test (for the dry limit). The methodology and results from laboratory experiments are also presented, and any links and discrepancies in representing field results were discussed. The thresholds established by the results of the laboratory tests agree well with the findings in the field. This allow that worability limits in terms of soil water potential can be established for other soils in the area by means the mentioned laboratory tests.This was the main part of this research since it was the development of the methodology to characterize the workable range of soils for the area under study.Once the workable range of a soil is known, whether this status is present on time (during the workable period within the cropping calendar) depends on the interactions between soil characteristics and weather. In Chapter 4, the necessary data used to model the soil-water balance in order to obtain the relevant information for tillage planning and operation, was discussed. The possibility of use PTF's for deriving the hydraulic characteristics of soils from limited textural data normally available in the area under study was explored, as they are required by deterministic soil-water models. It was found that PTF's developed in The Netherlands estimate well the hydraulic characteristics for a Loam soil of the area under study.The soil workability and the soil-water balance are the 'tools' to calculate the workable periods, but in this area the data available to determine both 'tools' is available at different spatial scales. The possibility of extending the methodology applied at the experimental field level to other scales and the use of workability information for operational decisions and planning was discussed in Chapter 5.To decide objectively which tillage practice will be chosen and when tillage should be carried out, a great deal of information has to be analyzed. To take advantage of the soil workability methodology developed, it shall be used within an automated procedure wherein the user need only supply its specific circumstances and receive as output the relevant information to utilize as support for planning decisions. In chapter 6 an initial version of such an automated procedure was presented.In Chapter 7 From results and discussions and having as reference the posed hypothesis, general conclusions were stated regarding the development and use of the methodology on soil workability to support the planning and operation of tillage systems in the area under study.</p

A field method for predicting the draught forces of tillage implements.

A literature review was conducted on several models which have been developed, based on Terzaghi's passive earth pressure theory, to describe the forces acting upon tillage implements during tillage operations. These models require a knowledge of cohesion (c) and angle of internal shearing resistance (cp) data which are not easy to obtain especially in remote areas. The main objective of the study was to establish a prediction model for the draught force required for a range of primary tillage implements under different field and soil conditions. The data obtained from the model were used to investigate whether the model was adequate for the mechanisation planning of the GAP region (South Eastern Anatolia Integrated Development Project) in Tiirkiye where by the year 2012, approximately 1.7 million ha ofland will be opened to irrigation. An effective three-point linkage dynamometer system was developed to measure the draught of implements under different soil conditions. The system consists of bi-axial Linkage Extended Octagonal Ring Transducers (LEORTs) for the lower links, a modified top link and a rotary position transducer sensing the angle of the crossshaft, together with a 21x datalogger and a portable computer. All transducers outputs were repeatable and linear with a co'efficient of determination of ~ 0.999. The output hysteresis effect was small for all transducers; the largest deviation from the mean was 1.006 % [f.s.] which occurred in the top link. Cross-sensitivity errors for the LEORTs were not significant at a maximum of 0.001 J.lV V-IN-I. A spreadsheet model was developed in order to download the data from the instrumentation system to the computer. The model is user friendly and can be used to calculate and plot the forces on the linkage system. Field experiments were conducted to determine draught force requirements of tillage implements such as a disc plough, mouldboard plough, chisel and subsoiler both under sandy loam soil conditions in UK and clay soil conditions in Tiirkiye. The standard tine which has a 450 rake angle was used as a reference tine. The field tests were Gonducted to examine the validation of a model for different soil conditions in UK such as dry, wet, light and heavy soil conditions

EXTRACTION AND CHARACTERIZATION OF OIL FROM PRE-MATURE PALM KERNEL

Palm kernel oil was extracted from crushed premature palm kernel using n-hexane as solvent. The experimental investigations reveal that the maximum yield of oil was obtained when the weight of the solvent used is equal to the weight of crushed premature palm kernel used. The particle size of 20 British standard sieve, that is 1.0795mm approximately is used and the temperature of the solvent is close to the boiling point, but solvent loss is so much that 50oC is recommended instead for laboratory and 60oC for industries. The characteristics of the oil were free fatty acid (0.78), iodine value (20.45), saponification value (179.35), acid value (1.54), smoke point (165oc) relative density (0.9011), peroxide value (0) and refractive index (1.432)

APPLICATION AND ENHANCEMENT OF LIFE CYCLE ASSESSMENT AND WATER FOOTPRINT APPROACHES TO AGRICULTURAL MACHINERY AND CULTIVATION

La sostenibilit\ue0 ambientale delle produzioni agricole ha riscosso ampio interesse in tutto il mondo. Per la comunit\ue0 scientifica, comprendere i sistemi produttivi agricoli nell\u2019ottica dell\u2019impatto ambientale, che consente di realizzare analisi con una prospettiva olistica, e quantificare i benefici ambientali derivanti dalla selezione di una serie di operazioni o un'altra, comporta la possibilit\ue0 di identificare e suggerire l'introduzione di miglioramenti vantaggiosi per la societ\ue0 e le generazioni future. Questa Tesi di Dottorato \ue8 stata finalizzata a studiare come rendere adeguatamente affidabili gli inventari per le valutazioni di sostenibilit\ue0 ambientale relativi ai sistemi produttivi agricoli in cui si utilizzano macchine agricole per le operazioni di campo. Per esse, le caratteristiche locali pedo-climatiche e organizzativo-produttive influenzano considerevolmente i dati di inventario e, di conseguenza, i risultati degli studi di sostenibilit\ue0 ambientale, qui realizzati secondo la metodologia del Life Cycle Assessment (LCA). Nel dettaglio, utilizzando l\u2019LCA, nella Tesi sono stati quantificati gli impatti ambientali delle operazioni agricole di campo per la preparazione del letto di semina (lavorazione del terreno primaria e secondaria) e per la distribuzione di fertilizzanti organici; ci\uf2 \ue8 stato fatto studiando l'uso di diverse macchine operatrici in diverse condizioni di lavoro. Di conseguenza, si \ue8 evidenziato quanto possono essere diversi i risultati di impatto ambientale relativi alla medesima operazione, ma ottenuti utilizzando dati di inventario riguardanti condizioni di lavoro \u201cmedie\u201d che vengono adottati acriticamente. Ci\uf2 \ue8 necessario per rendere consapevoli i decisori politici e tutte le parti interessate dell'importanza di evitare semplificazioni eccessive e informazioni generiche. Le diverse operazioni che sono state studiate, rappresentative per il contesto produttivo della Pianura Padana, sono state analizzate con ENVIAM (ENVironmental Inventory of Agricultural Machinery operations). ENVIAM \ue8 un foglio di calcolo sviluppato per quantificare i dati di inventario delle operazioni agricole considerando le variabili di tipo meccanico di trattori e macchine operatrici, le scelte sulla tipologia di accoppiamento tra gli stessi, la ripartizione dei tempi di lavoro e le variabili pedo-climatiche locali. I risultati ottenuti dalla relativa valutazione di impatto ambientale hanno mostrato delle differenze non trascurabili. Pertanto, risulta evidente come la scelta delle macchine (trattori e macchine operatrici) influenzi profondamente la sostenibilit\ue0 ambientale delle produzioni agricole, principalmente in termini di consumo di combustibile, olio lubrificante e materiali, nonch\ue9 delle emissioni dei gas di scarico del motore e delle sostanze nutritive rilasciate in aria, suolo e acqua. Tra questi, l'attenzione \ue8 stata rivolta ai combustibili e ai gas di scarico del motore e, per approfondire la conoscenza sul sistema e migliorare l\u2019affidabilit\ue0 dello strumento di calcolo di inventario, sono state eseguite delle prove su molteplici operazioni di campo utilizzando un trattore equipaggiato con GPS, CAN-bus, software di registrazione dei dati Dewesoft\uae e analizzatore di emissioni Testo\uae. Ci\uf2 ha consentito di raccogliere dati durante le operazioni in campo ed elaborarli per ciascuno degli stati di lavoro identificati (lavoro effettivo, svolte in capezzagna, tempi di stop e trasporto). Inoltre, nella Tesi di Dottorato \ue8 stata eseguita un'analisi sull'indicatore Water Footprint (WF) poich\ue9 la risorsa idrica \ue8 fondamentale per le produzioni agricole e per le problematiche di sostenibilit\ue0 ambientale. Analizzando la letteratura sono emerse delle critiche metodologiche sull'approccio di calcolo adottato per il WF, principalmente in relazione alla quantificazione di WFblue e WFgrey. Pertanto, sono stati suggeriti alcuni miglioramenti, tra cui l\u2019introduzione del Pollution Water Indicator (PWI) che permette di valutare qualitativamente il WFgrey con il supporto delle categorie di impatto caratteristiche dell\u2019LCA che si riferiscono all\u2019impatto sulla risorsa idrica. I risultati ottenuti dall'analisi delle operazioni di campo e dalla valutazione sui dati per la compilazione degli inventari hanno permesso di identificare le combinazioni alternative di trattori e macchine operatrici che hanno un impatto ambientale pi\uf9 contenuto rispetto ad altri. Inoltre, sono state identificate le condizioni di lavoro che dovrebbero essere adottate positivamente quando si lavora con il trattore utilizzato durante le prove di campo e le misure in campo hanno anche permesso di avere dati affidabili per quantificare l'impatto ambientale delle operazioni analizzate. Infine, per quanto riguarda lo studio del WF, i risultati ottenuti dall'introduzione del PWI hanno permesso di valutare l'inquinamento della risorsa idrica nelle produzioni agricole senza omettere importanti inquinanti. In conclusione, i risultati di questa Tesi di Dottorato possono essere adottati per avere una metodologia di analisi dei sistemi produttivi che consenta di valutare la variabilit\ue0 locale e di raggiungere una maggiore affidabilit\ue0 nei risultati e, inoltre, per aiutare i decisori politici a introdurre politiche e sistemi di incentivazione adeguati a supportare la sostenibilit\ue0 ambientale dei sistemi agro-alimentari.The environmental sustainability of agricultural productions has gained wide interest worldwide. For the scientific community, understanding the behaviour of agricultural production systems on the environmental impact perspective with a holistic view and quantifying the environmental benefits arising from the selection of a sequence of operations or another, permits to identify and suggest the introduction of beneficial improvements for society and future generations. This PhD Thesis was aimed to study how to make adequately reliable the inventories in view of performing environmental sustainability assessments about agricultural machinery production systems. For these, local pedo-climatic and work-specific characteristics affect considerably both the completion of inventories and the outcomes of Life Cycle Assessment (LCA) studies. In detail, in this Thesis are quantified with LCA the environmental impacts of agricultural field operations for seedbed preparation (i.e. primary and secondary soil tillage) and for organic fertilisers spreading techniques. This has been done by studying the use of different machinery in different working conditions and, consequently, highlighting how different environmental outcomes can be obtained when average inventory data are used uncritically. This makes policy makers and stakeholders aware of the importance of avoiding such simplifications and general information. The alternative operations that were studied, representative of the Italian Po Valley, were analysed with the tool ENVIAM (ENVironmental Inventory of Agricultural Machinery operations). ENVIAM was developed to quantify inventory data for agricultural field operations, considering the mechanical variability of machinery (i.e. of tractors and implements), the coupling choices between tractor and implement, the organisation of working time and the local pedo-climatic variables. The related environmental impact results showed not negligible differences. Accordingly, the choice of machinery greatly influences the environmental sustainability of agricultural productions, mainly in terms of fuel consumption, lubricating oil and materials consumption as well as of emissions of engine exhaust gases and of nutrients to air, soil and water. Among them, the focus was paid to fuel and engine exhaust gases. For deepening knowledge and improving the reliability of the inventory calculation tool, field tests on several field operations were carried out using a tractor equipped with GPS, CAN-bus, Dewesoft\uae data logger and Testo\uae emissions analyser. This allowed collecting data during field operations and processing them within the identified work states (i.e. effective work, turns at the headlands, stops and transport). In addition, in the PhD Thesis an analysis of the Water Footprint (WF) indicator was carried out, because water resource is crucial for agricultural productions and environmental sustainability issues. By reviewing the literature, methodological criticisms emerged about the Water Footprint Network approach, mostly in relation to the quantification of WFblue and WFgrey. Therefore, some improvements have been suggested, among which the introduction of the Pollution Water Indicator (PWI). It was proposed to qualitatively evaluate WFgrey with the support of LCA\u2019s impact categories that relate to the impact on water resources. The results got from the analysis of agricultural machinery operations and inventory data completion permitted to identify the alternatives for machinery that have a more restrained environmental impact respect to others. Moreover, the work conditions that should be adopted when working with the tractor used during the field trials were identified, which also allowed having reliable data for quantifying the environmental impact of the analysed field operations. Finally, regarding the WF study, the results that were obtained from the use of PWI permitted to assess water pollution of agricultural productions without omitting important pollutant sources. In conclusion, the outcomes of this PhD Thesis can be adopted to have a methodology for analysing local production systems that allows assessing local variability and achieving greater reliability in the results and, moreover, to help policy makers introduce policies and incentive systems appropriate to support the environmental sustainability of agri-food systems