Simulation of 2D Riser Regenerator

Riser regenerators are regenerating vessels used for removing the coke deposited on the catalyst and provide heat of reaction for the cracking process. Coke formation is unavoidable in the catalytic cracking process, which is probably formed by the dehydrogenation and condensation of poly-aromatic and olefins. Fast deactivation by blocking the active pores of the catalyst is a consequence of coke deposition. Riser regenerators are used for regenerating spent FCC catalyst by burning the coke deposited on the catalyst body. These are better compared to the conventional turbulent fluidised beds due to large capacities, higher gas-solid contact efficiency, high heat and mass transfer rates and low solids inventory. These regenerators also offer advantages over conventional scale reactors such as reaction speed, greater combustion of coke, reliability, cost effective, scalability and better safety and control. The present work is aimed to study the behaviour of regeneration reaction of coke inside riser regenerator. The advantages of multiple air inlet riser regenerator have been found out by studying the phenomenon inside the regenerator. The transient simulation has been carried out. The transient solution shows the species concentration and temperature profile inside the riser regenerators. The result reveals that the temperature of the gas increases with axial length and species concentration decreases. It has been found that multiple air inlet regenerator provide a better combustion than the single inlet regenerator

NASA Tech Briefs, February 1994

Topics covered include: Test and Measurement; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences; Books and Report

Design and control of a loader mechanism for the NMBU agricultural robot

Despite the development of new technologies, manual labour still continuous to play a large role within most modern agricultural operations, especially during harvest. Consequently, there is an increasing demand for new machines to reduce labour as a mean to limit costs, while increasing efficiency in a sustainable manner. This thesis concern itself with the design of a mechanism and control system for a robot arm that can substitute workers in logistical operations during strawberry harvest. More specifically, by lifting berry crates onto a robot platform and transporting them from the fields and to the packaging facilities. The robot arm is to be mounted on the platform composing a vehicle- manipulator system. As this thesis is connected to a general research project on agricultural robotics at the Norwegian University of Life Sciences, the chosen platform is the associated field robot Thorvald II. The thesis is divided into two parts, where Part I concerns the mechanical design of the robot arm, while Part II propose a system for controlling the mechanism. The design development process has involved assessments of available solutions before selecting components on the basis of controllability, mechanical properties and costs. The process of selection in Part II is however, based on finding solutions that are compatible with the robot platform’s network (Controller Area Network) and operating system (Robotic Operating System). Part I: Design and Mechanics The design of the robot arm presented in this thesis begun with a preliminary feasibility study conducted by Bjurbeck in September 2016. Following the assessment of this study, the robot arm is designed to have two degrees of freedom operating in the xz-plane. When mounted on the platform, the arm will be free to operate in a 3-dimensional space, as the platform moves in x and y-direction, and rotates around the z-axis. The arm is assembled from two parallel link pairs made from rectangular aluminium tubes, and a revolute and prismatic joint. Both joints are actuated by LinAk LA36 linear electric actuators. The end effector of the arm is a gripper head designed to grasp the handles of the strawberry crate. The gripper head is self-aligning with the crate’s orientation in order to reduce the precision of control needed to envelop and grasp the crate. The frame of the gripper head is made from aluminium angle profiles and sheet metal. A worm drive DC motor actuate the gripper claws via a double link mechanism. Part II: Modeling and Control The geometry of the design presented in Part I is modelled mathematically and the inverse kinematics solved analytically. The kinematics will be used in future implementation of a position control system. Two RoboteQ SDC2160 dual-channel controllers are chosen to control all four actuator mo- tors. The linear actuators are controlled in closed loop position tracking mode with absolute feedback. The gripper motor is controlled in open loop mode with end stop switches detecting the position of the claws. Experiments was conducted to match the controllers with the actuator motors. The experiments revealed firmware issues with the controller. The experiments also affirmed the controller need a script to operate the actuators efficiently. The thesis provides the foundations to build a prototype and write an operating script to test the mechanical design and control system.Til tross for den stadige utviklingen av ny teknologi spiller manuelt arbeid fortsatt en stor rolle i moderne landbruk, særlig i innhøsting. På grunn av den store arbeidkraften som trengs er det en stadig større etterspørsel etter nye maskiner som kan redusere behovet for manuelt arbeid for å redusere utgifter og effektivisere gårdsbruk på en bærekraftig måte. Denne masteroppgaven omhandler det mekaniske designet og reguleringssystemet til en robotarm laget for å kunne erstatte arbeidere i oppgaver tilknyttet logistikk ved innhøsting av jordbær. Dette gjøres ved at armen løfter kasser med bær opp på en robotplattform som transporterer kassene fra jordet og til et pakkeri. Robotarmen er da montert oppå plattformen. Siden oppgaven er tilknyttet et forskningsprosjekt i landbruksrobotikk ved Norges miljø- og biovitenskapelige universitet, var det naturlig å velge den universitetets robot Thorvald II som plattform.submittedVersionM-MP

Transforming traditional mechanical and electrical construction to a modern process of assembly

This thesis presents the findings of a research project to develop and implement a Lean and agile Construction System on a case study project. The aim of the research project, for the sponsor company, was to improve its projects site operations, making them safer for the worker and improving effectiveness and productivity. The findings have shown that the Construction System has proved to be a successful set of countermeasures that act as an antidote to the health, safety and productivity problems that exist in UK construction and that face the sponsor company. The System has been implemented on a large and complex mechanical and electrical case study project in the healthcare sector of UK construction. The outcome of this case study project shows that 37% less onsite labour was needed, meaning fewer workers were exposed to health and safety risks from site operations, leading to zero reportable accidents. Good ergonomics was achieved by focussing on workplace design, thus improving workers wellbeing, together with an improved quality of work for those required on site carrying out simpler assembly tasks. Productivity gains resulted by eliminating process waste, therefore reducing the risk of labour cost escalation that could otherwise have occurred. A 7% direct labour cost reduction was made meaning the labour budget allocation was maintained. Significantly, an overall productivity of 116% was achieved using the Construction System, which compares favourably to BSRIA’s findings of an average overall productivity of only 37% when compared to observed best practice for the projects in that case study research. The results include the benefits found from the use of an innovative method to assemble, transport, and install frameless, preassembled mechanical and electrical services modules, where a 93% reduction in onsite labour was achieved together with an 8.62% cost benefit. No time slippage was experienced during onsite assembly to delay or disrupt other trades and the commissioning programme was not compressed that could otherwise have caused problems in handing over the facility to the customer. From a customer’s perspective, the built facilities were handed over on-time, to their satisfaction and to budget. The research has achieved two levels of innovation, one at a process level and one at a product level. The process innovation is the development and successful implementation of the Construction System, which is a combination of methods acting together as an antidote to the research problem. The product innovation is the development of the innovative method for assembling, transporting and installing frameless mechanical and electrical corridor modules, whereby modularisation can be achieved with or without an offsite manufacturing capability. The System is built on Lean principles and has been shown to standardise the work, process and products to create flow, pull and value delivery. It is transferable across the sponsor company’s business as well as the wider industry itself. The transformation that has occurred is the creation of a step-change in undertaking mechanical and electrical construction work, which has realised a significant improvement in performance for CHt that has “Transformed Traditional Mechanical and Electrical Construction into a Modern Process of Assembly”

Simulation of site-specific irrigation control strategies with sparse input data

Crop and irrigation water use efficiencies may be improved by managing irrigation application timing and volumes using physical and agronomic principles. However, the crop water requirement may be spatially variable due to different soil properties and genetic variations in the crop across the field. Adaptive control strategies can be used to locally control water applications in response to in-field temporal and spatial variability with the aim of maximising both crop development and water use efficiency. A simulation framework ‘VARIwise’ has been created to aid the development, evaluation and management of spatially and temporally varied adaptive irrigation control strategies (McCarthy et al., 2010). VARIwise enables alternative control strategies to be simulated with different crop and environmental conditions and at a range of spatial resolutions. An iterative learning controller and model predictive controller have been implemented in VARIwise to improve the irrigation of cotton. The iterative learning control strategy involves using the soil moisture response to the previous irrigation volume to adjust the applied irrigation volume applied at the next irrigation event. For field implementation this controller has low data requirements as only soil moisture data is required after each irrigation event. In contrast, a model predictive controller has high data requirements as measured soil and plant data are required at a high spatial resolution in a field implementation. Model predictive control involves using a calibrated model to determine the irrigation application and/or timing which results in the highest predicted yield or water use efficiency. The implementation of these strategies is described and a case study is presented to demonstrate the operation of the strategies with various levels of data availability. It is concluded that in situations of sparse data, the iterative learning controller performs significantly better than a model predictive controller

Air pollution and livestock production

The air in a livestock farming environment contains high concentrations of dust particles and gaseous pollutants. The total inhalable dust can enter the nose and mouth during normal breathing and the thoracic dust can reach into the lungs. However, it is the respirable dust particles that can penetrate further into the gas-exchange region, making it the most hazardous dust component. Prolonged exposure to high concentrations of dust particles can lead to respiratory health issues for both livestock and farming staff. Ammonia, an example of a gaseous pollutant, is derived from the decomposition of nitrous compounds. Increased exposure to ammonia may also have an effect on the health of humans and livestock. There are a number of technologies available to ensure exposure to these pollutants is minimised. Through proactive means, (the optimal design and management of livestock buildings) air quality can be improved to reduce the likelihood of risks associated with sub-optimal air quality. Once air problems have taken hold, other reduction methods need to be applied utilising a more reactive approach. A key requirement for the control of concentration and exposure of airborne pollutants to an acceptable level is to be able to conduct real-time measurements of these pollutants. This paper provides a review of airborne pollution including methods to both measure and control the concentration of pollutants in livestock buildings

Advances in Fluid Power Systems

The main purpose of this Special Issue of “Advances in Fluid Power Systems” was to present new scientific work in the field of fluid power systems for hydraulic and pneumatic control of machines and devices used in various industries. Advances in fluid power systems are leading to the creation of new smart devices that can replace tried-and-true solutions from the past. The development work of authors from various research centres has been published. This Special Issue focuses on recent advances and smart solutions for fluid power systems in a wide range of topics, including: • Fluid power for IoT and Industry 4.0: smart fluid power technology, wireless 5G connectivity in fluid power, smart components, and sensors.• Fluid power in the renewable energy sector: hydraulic drivetrains for wind power and for wave and marine current power, and hydraulic systems for solar power. • Hybrid fluid power: hybrid transmissions, energy recovery and accumulation, and energy efficiency of hybrid drives.• Industrial and mobile fluid power: industrial fluid power solutions, mobile fluid power solutions, eand nergy efficiency solutions for fluid power systems.• Environmental aspects of fluid power: hydraulic water control technology, noise and vibration of fluid power components, safety, reliability, fault analysis, and diagnosis of fluid power systems.• Fluid power and mechatronic systems: servo-drive control systems, fluid power drives in manipulators and robots, and fluid power in autonomous solutions

Design and Development of Sensor Integrated Robotic Hand

Most of the automated systems using robots as agents do use few sensors according to the need. However, there are situations where the tasks carried out by the end-effector, or for that matter by the robot hand needs multiple sensors. The hand, to make the best use of these sensors, and behave autonomously, requires a set of appropriate types of sensors which could be integrated in proper manners. The present research work aims at developing a sensor integrated robot hand that can collect information related to the assigned tasks, assimilate there correctly and then do task action as appropriate. The process of development involves selection of sensors of right types and of right specification, locating then at proper places in the hand, checking their functionality individually and calibrating them for the envisaged process. Since the sensors need to be integrated so that they perform in the desired manner collectively, an integration platform is created using NI PXIe-1082. A set of algorithm is developed for achieving the integrated model. The entire process is first modelled and simulated off line for possible modification in order to ensure that all the sensors do contribute towards the autonomy of the hand for desired activity. This work also involves design of a two-fingered gripper. The design is made in such a way that it is capable of carrying out the desired tasks and can accommodate all the sensors within its fold. The developed sensor integrated hand has been put to work and its performance test has been carried out. This hand can be very useful for part assembly work in industries for any shape of part with a limit on the size of the part in mind. The broad aim is to design, model simulate and develop an advanced robotic hand. Sensors for pick up contacts pressure, force, torque, position, surface profile shape using suitable sensing elements in a robot hand are to be introduced. The hand is a complex structure with large number of degrees of freedom and has multiple sensing capabilities apart from the associated sensing assistance from other organs. The present work is envisaged to add multiple sensors to a two-fingered robotic hand having motion capabilities and constraints similar to the human hand. There has been a good amount of research and development in this field during the last two decades a lot remains to be explored and achieved. The objective of the proposed work is to design, simulate and develop a sensor integrated robotic hand. Its potential applications can be proposed for industrial environments and in healthcare field. The industrial applications include electronic assembly tasks, lighter inspection tasks, etc. Application in healthcare could be in the areas of rehabilitation and assistive techniques. The work also aims to establish the requirement of the robotic hand for the target application areas, to identify the suitable kinds and model of sensors that can be integrated on hand control system. Functioning of motors in the robotic hand and integration of appropriate sensors for the desired motion is explained for the control of the various elements of the hand. Additional sensors, capable of collecting external information and information about the object for manipulation is explored. Processes are designed using various software and hardware tools such as mathematical computation MATLAB, OpenCV library and LabVIEW 2013 DAQ system as applicable, validated theoretically and finally implemented to develop an intelligent robotic hand. The multiple smart sensors are installed on a standard six degree-of-freedom industrial robot KAWASAKI RS06L articulated manipulator, with the two-finger pneumatic SHUNK robotic hand or designed prototype and robot control programs are integrated in such a manner that allows easy application of grasping in an industrial pick-and-place operation where the characteristics of the object can vary or are unknown. The effectiveness of the actual recommended structure is usually proven simply by experiments using calibration involving sensors and manipulator. The dissertation concludes with a summary of the contribution and the scope of further work

Capture and Maintenance of Constraints in Engineering Design

The thesis investigates two domains, initially the kite domain and then part of a more demanding Rolls-Royce domain (jet engine design). Four main types of refinement rules that use the associated application conditions and domain ontology to support the maintenance of constraints are proposed. The refinement rules have been implemented in ConEditor and the extended system is known as ConEditor+. With the help of ConEditor+, the thesis demonstrates that an explicit representation of application conditions together with the corresponding constraints and the domain ontology can be used to detect inconsistencies, redundancy, subsumption and fusion, reduce the number of spurious inconsistencies and prevent the identification of inappropriate refinements of redundancy, subsumption and fusion between pairs of constraints.EThOS - Electronic Theses Online ServiceGBUnited Kingdo