Chemical kinetics modelling study on fuel autoignition in internal combustion engines

Chemical kinetics has been widely acknowledged as a fundamental theory in analysis of chemical processes and the corresponding reaction outputs and rates. The study and application of chemical kinetics thus provide a simulation tool to predict many characteristics a chemical process. Oxidation of hydrocarbon fuels applied in internal combustion engines is a complex chemical process involving a great number of a series of chained reaction steps and intermediate and simultaneous species. Symbolic and Numerical description of such a chemical process leads to the development and application of chemical kinetics models. The up-to-date application of chemical kinetics models is to the simulation of autoignition process in internal combustion engines. Multi-zone thermodynamic combustion modelling has been regarded as a functional simulation approach to studying combustion process in IC engines as a decent compromise between computation accuracy and efficiency. Integration of chemical kinetics models into multi-zone models is therefore a potential modelling method to investigate the chemical and physical processes of autoignition in engine combustion. This research work has been therefore concerned with the development, validation and application of multi-zone chemical kinetic engine models in the simulation of autoignition driven combustion in SI and HCCI engines. The contribution of this work is primarily made to establish a mathematical model based on the underlying physical and chemical principles of autoignition of the fuel-air mixture in SI and HCCI engines. Then, a computer code package has been developed to numerically solve the model. The derived model aims at improving the understanding of autoignition behaviour under engine-like conditions and providing an investigative tool to autoignition characteristics. Furthermore, as part of the ongoing program in the research of free piston engines, the results of this work will significantly aid in the investigation and simulation of the constant volume autoignition applied in free piston engines

Building Information Modelling (BIM) aided waste minimisation framework

Building design can have a major impact on sustainability through material efficiency and construction waste minimisation (CWM). The construction industry consumes over 420 million tonnes of material resources every year and generates 120 million tonnes of waste containing approximately 13 million tonnes of unused materials. The current and on-going field of CWM research is focused on separate project stages with an overwhelming endeavour to manage on-site waste. Although design stages are vital to achieve progress towards CWM, currently, there are insufficient tools for CWM. In recent years, Building Information Modelling (BIM) has been adopted to improve sustainable building design, such as energy efficiency and carbon reduction. Very little has been achieved in this field of research to evaluate the use of BIM to aid CWM during design. However, recent literature emphasises a need to carry out further research in this context. This research aims to investigate the use of BIM as a platform to help with CWM during design stages by developing and validating a BIM-aided CWM (BaW) Framework. A mixed research method, known as triangulation, was adopted as the research design method. Research data was collected through a set of data collection methods, i.e. selfadministered postal questionnaire (N=100 distributed, n=50 completed), and semistructured follow-up interviews (n=11) with architects from the top 100 UK architectural companies. Descriptive statistics and constant comparative methods were used for data analysis. The BaW Framework was developed based on the findings of literature review, questionnaire survey and interviews. The BaW Framework validation process included a validation questionnaire (N=6) and validation interviews (N=6) with architects. Key research findings revealed that: BIM has the potential to aid CWM during design; Concept and Design Development stages have major potential in helping waste reduction through BIM; BIM-enhanced practices (i.e. clash detection, detailing, visualisation and simulation, and improved communication and collaboration) have impacts on waste reduction; BIM has the most potential to address waste causes (e.g. ineffective coordination and communication, and design changes); and the BaW Framework has the potential to enable improvements towards waste minimisation throughout all design stages. Participating architects recommended that the adoption of the BaW Framework could enrich both CWM and BIM practices, and most importantly, would enhance waste reduction performance in design. The content should be suitable for project stakeholders, architects in particular, when dealing with construction waste and BIM during design

Chemical kinetics modelling study on fuel autoignition in internal combustion engines

Chemical kinetics has been widely acknowledged as a fundamental theory in analysis of chemical processes and the corresponding reaction outputs and rates. The study and application of chemical kinetics thus provide a simulation tool to predict many characteristics a chemical process. Oxidation of hydrocarbon fuels applied in internal combustion engines is a complex chemical process involving a great number of a series of chained reaction steps and intermediate and simultaneous species. Symbolic and Numerical description of such a chemical process leads to the development and application of chemical kinetics models. The up-to-date application of chemical kinetics models is to the simulation of autoignition process in internal combustion engines. Multi-zone thermodynamic combustion modelling has been regarded as a functional simulation approach to studying combustion process in IC engines as a decent compromise between computation accuracy and efficiency. Integration of chemical kinetics models into multi-zone models is therefore a potential modelling method to investigate the chemical and physical processes of autoignition in engine combustion. This research work has been therefore concerned with the development, validation and application of multi-zone chemical kinetic engine models in the simulation of autoignition driven combustion in SI and HCCI engines. The contribution of this work is primarily made to establish a mathematical model based on the underlying physical and chemical principles of autoignition of the fuel-air mixture in SI and HCCI engines. Then, a computer code package has been developed to numerically solve the model. The derived model aims at improving the understanding of autoignition behaviour under engine-like conditions and providing an investigative tool to autoignition characteristics. Furthermore, as part of the ongoing program in the research of free piston engines, the results of this work will significantly aid in the investigation and simulation of the constant volume autoignition applied in free piston engines

A zero-dimensional combustion model with reduced kinetics for SI engine knock simulation

High load performance and fuel economy of gasoline engines are limited by knocks. Such limitations are becoming worse when the engine is heavily super-charged for high BMEP outputs. Spark ignition timing retardation has been an efficient method to avoid the knock but results in reduced engine performance and poor fuel economy. A better understanding of knock, which could be used to optimize the engine design, ignition timing optimization in particular, is important. In this research, a simulation model for SI engine knock has been developed. The model is based on a three-zone approach (unburned, burning and burned zones). The Tanaka’s reduced chemical kinetic model for a commercial gasoline fuel with an RON of 95 has been modified and applied in both burned and unburned zones incorporated with the LUCKS (Loughborough University Chemical Kinetics Simulation) code. Both post-flame heat release and pre-flame autoignition have be simulated. The burning zone uses equilibrium combustion thermodynamic models. The simulated results have been validated against experimental results, and good agreements have been achieved

Integration of building information modelling (BIM) and sensor technology: A review of current developments and future outlooks

© 2018 Association for Computing Machinery. ACM. Building Information Modelling1 (BIM) is revolutionising the practicalities of current construction field, sensor technology is essential for enabling BIM to extend beyond the domain of software into the physical domain of building construction and operation; however, no prior in-depth review has focused on the integration of BIM and sensor technology. This paper provides a brief review to evaluate and clarify the state-of-art for the integration of BIM and sensor technology. A systematic review approach was adopted. The result reveals that although much research has conducted, there are gaps and scope for further work, namely: (a) More consideration of the cost of sensors needs to be taken; (b) More commercial applications should be developed; (c) Higher accuracy of positioning and tracing is needed; (d) More applications in structural design could be expanded

Building Information Management (BIM) and blockchain (BC) for sustainable building design information management framework

At present, sustainable design is experiencing energy consumption and cost-effectiveness challenges in the building industry. A recent body of literature argues that the development of emerging smart digital technologies, such as Building Information Management (BIM) and blockchain (BC), offer immediate benefits to the industry. However, the current application of BIM and BC in the sustainable design and construction process focuses on smart energy and construction management, with little attention to addressing challenges for applying BIM to sustainable design and proposing strategies in terms of the usability of these technologies in the management of building construction projects. Therefore, this paper sets out to explore the potential roles of an integrated BIM and BC approach for sustainable building design information management. The first attempt is presented to use BC aided BIM for sustainable building design coordination and collaboration in multiple building stages. BC has the potential to address challenges that hinder the industry from using BIM for sustainable design, which has been unearthed. An innovative BC enhanced transaction process in BIM is required for sustainable building development. Roles of a user level driven smart contract system of BC can be used to enhance BIM system in the sustainable buildings process. The role of BC is primarily at user level driven smart contracts and their record value exchange capabilities. A user level (BIM stakeholders) driven BC technology for transaction in BIM process flow is revealed, and the user level (sustainable building design project stakeholders/BIM clients) driven and the smart contract enabled BIM+ BC architecture to address challenges of BIM for sustainable design has been further circulated according to the literature. Subsequently, a conceptual architecture of BIM + BC for Sustainable Building Design Information Management Framework in building project management has been proposed, validated, and refined. The Framework has two level encompassing structures and flow. The high-level framework is focused on strategy, whilst the low-level framework demonstrates technical components in detail. This architecture supporting project stakeholders in managing information, has the potential to achieve and ensure the realization of sustainable design goals through the interactive realization of smart contracts integrated into the user level driven BIM + BC system and its recording value exchange function through three user-driven levels, namely user, system, and transaction

A BIM-aided construction waste minimisation framework

At present, there are insufficient design decision making tools to support effective construction waste minimisation evaluation and implementation throughout all design stages. A limited but growing body of recent literature suggests that building information modelling has the potential to assist architects to minimise design waste on their projects. The research reported in this paper is the first attempt to develop a design decision making framework for improving construction waste minimisation performance through building information modelling. The potential use of building information modelling to drive out construction waste in building design was investigated through a questionnaire survey and follow-up interview with the top 100 architectural practices in the United Kingdom. An industry-reviewed 'building information modelling-aided construction waste minimisation framework' was developed based on the results of the literature review, questionnaire data, and interview data. The Framework is intended to act as an integrated platform for designing out waste decision making, by providing informed building information modelling-driven guidance to address waste causes throughout design stages

The Effect of the Sloping Land Conversion Programme on Farm Household Productivity in Rural China

<p>The objective of this paper is to examine the treatment effect on farm household productivity induced by the Sloping Land Conversion Program. Using large balanced household level data from five provinces during 1996–2010, this study shows that the SLCP significantly improved the productivity of participants during the first round of funding of the programme until 2008, while the effects decreased gradually in the second round with most years not showing significant differences. Moreover, it is found that there are heterogeneous effects on farm household productivity between the south and north, as well as between poor and rich regions.</p

Multi-zone kinetic model of Controlled Auto Ignition combustion

A multi-zone Controlled Auto Ignition (CAI) model for simulating the combustion and emissions has been developed and reported in this paper. The model takes into account the effects of the boundary layer, crevice volume, and blowby. In order to investigate the influences of in-cylinder inhomogeneity, the main cylinder chamber has been divided into multiple core zones with varying temperature and composition. Mass and energy transfer between neighbouring zones were modeled. A reduced chemical kinetic mechanism was implemented in each zone to simulate the CAI combustion chemistry and emission formation. An in-house code, the LUCKS (Loughborough University Chemical Kinetics Simulation), was employed to solve the coupled differential equations of the system. The model was validated against experimental results at various Internal Exhaust Gas Recirculation (IEGR) levels and was then used to analyze the thermal and chemical effect of the IEGR on the CAI combustion. Good agreement between modeling and experimental results in terms of major CAI combustion parameters and emissions (CO, HC, and NOx) has been achieved

Facile Preparation of Glycoprotein-Imprinted 96-Well Microplates for Enzyme-Linked Immunosorbent Assay by Boronate Affinity-Based Oriented Surface Imprinting

Molecularly imprinted polymers (MIPs), as inexpensive and stable substitutes of antibodies, have shown great promise in immunoassays. Glycoproteins are of significant diagnostic value. To facilitate the application of MIPs in clinical diagnostics, a general and facile imprinting method toward glycoproteins oriented for an enzyme-linked immunosorbent assay (ELISA) in the form of a 96-well microplate is essential but has not been fully explored yet. In this study, a new method called boronate affinity-based oriented surface imprinting was proposed for facile preparation of glycoprotein-imprinted microplates. A template glycoprotein was first immobilized by a boronic acid-modified microplate through boronate affinity binding, and then, a thin layer of polyaniline was formed to cover the microplate surface via in-water self-copolymerization. After the template was removed by an acidic solution, 3D cavities that can rebind the template were fabricated on the microplate surface. Using horseradish peroxidase (HRP) as a model target, the effects of imprinting conditions as well as the properties and performance of the prepared MIPs were investigated. α-Fetoprotein (AFP)-imprinted microplate was then prepared, and thereby, a MIP-based ELISA method was established. The prepared MIPs exhibited several highly favorable features, including excellent specificity, widely applicable binding pH, superb tolerance for interference, high binding strength, fast equilibrium kinetics, and reusability. The MIP-based ELISA method was finally applied to the analysis of AFP in human serum. The result was in good agreement with that by radioimmunoassay, showing a promising prospect of the proposed method in clinical diagnostics