Developing Effervescent Atomisation for Alternative Fuels

2012 ◽  
Author(s):  
Dancho D. Konstantinov ◽  
Philip J. Bowen ◽  
Richard Marsh ◽  
Peter J. Kay ◽  
Andrew P. Crayford ◽  
...  
Keyword(s):  
Literature Review ◽  
Alternative Fuels ◽  
Combustion Process ◽  
Volume Ratio ◽  
Industrial Applications ◽  
Quality Data ◽  
Operating Parameters ◽  
Extensive Literature ◽  
Two Phase ◽  
Wide Range

A wide range of atomiser types have been developed for industrial applications — such as rotary, pressure, air-assist and air-blast atomisers. Each type works on the principle of applying mechanical or kinetic energy to disintegrate a jet or sheet of liquid fuel, in preparation for combustion. The aim is to sufficiently increase the surface area to volume ratio of the fuel and presents it in a form suitable for a consistent combustion process. Traditional liquid fuels, such as fossil fuels, have been employed for some decades and combustion systems (and atomisers) have been optimised for their use. However, combustion engineers are being increasingly forced to consider the use of alternative, biologically-derived hydrocarbon fuels. Such fuels often have very different viscosities, densities and surface tensions or possess complex, non-linear properties when compared to conventional fuels. Effervescent atomisation is a promising two-phase atomisation technique offering potential improvements in fluid atomisation quality and reductions in fluid operating pressures. It appears particularly well suited to the atomisation of viscous fuels such as biofuels; this applicability to alternative fuels has led to a renewed interest in the method. After an extensive literature review of the current state of this technology [1] an adjustable geometry effervescent atomiser was designed, built and studied at the Cardiff School of Engineering. Water and air were used as the operating fluids. The sprays produced by the atomiser were characterised using a Phase Doppler Anemometry (PDA) system which allowed for simultaneous real-time droplet size and velocity data to be obtained. High quality data was achieved with data rates over 10 kHz and validation rates over 90% in 2-D LDA mode in the high density sprays. A PDA probe designed for dense spray applications was utilised. A number of important operating parameters identified during the literature review phase can be altered on the atomiser, and their effects on fuel spray quality investigated. The operating parameters investigated in this manner included air-to-liquid by mass ratio (ALR), pressure drop as well as a range of geometric parameters. This paper discusses and analyses the influence of ALR on the quality of atomisation and the associated two-phase flow field. Comparisons are made with previous studies and correlations, using earlier versions of the hardware or alternative techniques. Ongoing work will assess and optimise the performance of simulated biofuels mixtures.

Developing a two-phase QFD for improving FMEA: an integrative approach

2019 ◽  
Vol 36 (8) ◽  
pp. 1454-1474 ◽  
Author(s):  
Fatemeh Shaker ◽  
Arash Shahin ◽  
Saeed Jahanyan
Keyword(s):  
Literature Review ◽  
Failure Modes ◽  
Continuous Production ◽  
Integrative Approach ◽  
Importance Rating ◽  
Second Phase ◽  
Extensive Literature ◽  
Two Phase ◽  
Content Type ◽  
Wide Range

Purpose The purpose of this paper is to propose an integrative approach for improving failure modes and effects analysis (FMEA). Design/methodology/approach An extensive literature review on FMEA has been performed. Then, an integrative approach has been proposed based on literature review. The proposed approach is an integration of FMEA and quality function deployment (QFD). The proposed approach includes a two-phase QFD. In the first phase, failure modes are prioritized based on failure effects and in the second phase, failure causes are prioritized based on failure modes. The proposed approach has been examined in a case example at the blast furnace operation of a steel-manufacturing company. Findings Results of the case example indicated that stove shell crack in hot blast blower, pump failure in cooling water supply pump and bleeder valves failed to operate are the first three important failure modes. In addition, fire and explosion are the most important failure effects. Also, improper maintenance, over pressure and excess temperature are the most important failure causes. Findings also indicated that the proposed approach with the consideration of interrelationships among failure effects, failure mode and failure causes can influence and adjust risk priority number (RPN) in FMEA. Research limitations/implications As manufacturing departments are mostly dealing with failure effects and modes of machinery and maintenance departments are mostly dealing with causes of failures, the proposed model can support better coordination and integration between the two departments. Such support seems to be more important in firms with continuous production lines wherein line interruption influences response to customers more seriously. A wide range of future study opportunities indicates the attractiveness and contribution of the subject to the knowledge of FMEA. Originality/value Although the literature indicates that in most of studies the outcomes of QFD were entered into FMEA and in some studies the RPN of FMEA was entered into QFD as importance rating, the proposed approach is a true type of the so-called “integration of FMEA and QFD” because the three main elements of FMEA formed the structure of QFD. In other words, the proposed approach can be considered as an innovation in the FMEA structure, not as a data provider prior to it or a data receiver after it.

scholarly journals BIM and DfMA: A Paradigm of New Opportunities

2021 ◽  
Vol 13 (17) ◽  
pp. 9591
Author(s):  
Sepehr Abrishami ◽  
Rocío Martín-Durán
Keyword(s):  
Literature Review ◽  
Conceptual Framework ◽  
Energy Use ◽  
Integrated Approach ◽  
Design Stage ◽  
Extensive Literature ◽  
Sources Of Information ◽  
Construction Methods ◽  
Wide Range

The main goal of this study is to explore the adoption of a design for manufacturing and assembly (DfMA) and building information management (BIM) approach during the whole lifecycle of assets. This approach aims to tackle issues inherent in the design of traditional construction methods, such as low productivity and quality, poor predictability and building performance, and energy use, through the implementation of a BIM library of off-site components. In recent years, a renewed interest has been directed to the attempt to provide solutions to these urgent problems through the adoption of new advancements in technologies. However, while there are studies focussing on a BIM-DfMA approach, there is a lack of research regarding how this approach should be adopted during the whole lifecycle of the assets. Furthermore, to the best of our knowledge, defining an efficient way of developing a component-based BIM object library has not yet been included in any of the available studies. A mixed methodology approach has been used in this research. A conceptual framework was developed as the result of an extensive literature review to investigate new advancements in the AEC sector. Following the literature review, the framework was tested and validated through a case study based on the production and adoption of a BIM library of off-site components at the design stage of an asset. The architecture, engineering, and construction (AEC) industry has recognised the necessity of a new approach that helps to resolve the well-known issues presented in traditional methods of construction. The conceptual framework and case study proposed presents a valuable new method of construction that support the implementation of a BIM and DfMA approach, highlighting their benefits. This framework has been created using many valuable and reliable sources of information. The result of this research supports the idea of a novel new construction method that focuses on a manufacturing-digital-driven industry, with the use of DfMA in a BIM-integrated approach. This novel method will add significance and be beneficial for a wide range of aspects in the construction sector, contributing to the theoretical and practical domain.

scholarly journals Influence of Spray Nozzle Operating Parameters on the Fogging Process Implemented to Prevent the Spread of SARS-CoV-2 Virus

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4280
Author(s):  
Waldemar Fedak ◽  
Roman Ulbrich ◽  
Grzegorz Ligus ◽  
Marek Wasilewski ◽  
Szymon Kołodziej ◽  
...  
Keyword(s):  
Droplet Diameter ◽  
Diameter Distribution ◽  
Operating Parameters ◽  
Two Phase ◽  
Weighting Method ◽  
Spray Cone ◽  
Air Supply ◽  
Wide Range ◽  
Flow Intensity ◽  
Pressure Swirl

This article reports the results of a study into the effect of operating parameters on the occurrence and course of gas–liquid two-phase phenomena during the fogging process carried out with the use of a conical pressure-swirl nozzle. Four alternatives of the stub regulation angles and four values of pressure of air supply to the nozzle were tested as part of the current research. The range of the investigated variables was common for the operation of fumigators used to prevent the spread of SARS-CoV-2 virus. The liquid flow rate (weighting method), the field of velocity, and turbulent flow intensity factor, as well as velocity profiles over the section of 1 m from the nozzle were determined using the particle image velocimetry (PIV) technique. The obtained results were correlated with the measurements of the diameters of spray droplets using the laser light scattering (LLS) technique. On the basis of this research, a dependence between the nozzle parameters and the spray cone pattern was identified in terms of dynamics and droplet diameter distribution. As a result of the research, a wide range of parameters were identified in which the fogging process was carried out in a stable and repeatable manner. There were exceptions to this rule only in the cases when there was a deficiency of the liquid necessary to generate a two-phase mixture.

scholarly journals Alternative Fuels from Forestry Biomass Residue: Torrefaction Process of Horse Chestnuts, Oak Acorns, and Spruce Cones

Energies ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2468 ◽  
Author(s):  
Arkadiusz Dyjakon ◽  
Tomasz Noszczyk
Keyword(s):  
Carbon Content ◽  
Alternative Fuels ◽  
Combustion Process ◽  
Energy System ◽  
Hard Coal ◽  
Energy Yield ◽  
Fixed Carbon ◽  
Heating Value ◽  
Wide Range ◽  
Fixed Carbon Content

The global energy system needs new, environmentally friendly, alternative fuels. Biomass is a good source of energy with global potential. Forestry biomass (especially wood, bark, or trees fruit) can be used in the energy process. However, the direct use of raw biomass in the combustion process (heating or electricity generation) is not recommended due to its unstable and low energetic properties. Raw biomass is characterized by high moisture content, low heating value, and hydrophilic propensities. The initial thermal processing and valorization of biomass improves its properties. One of these processes is torrefaction. In this study, forestry biomass residues such as horse chestnuts, oak acorns, and spruce cones were investigated. The torrefaction process was carried out in temperatures ranging from 200 °C to 320 °C in a non-oxidative atmosphere. The raw and torrefied materials were subjected to a wide range of tests including proximate analysis, fixed carbon content, hydrophobicity, density, and energy yield. The analyses indicated that the torrefaction process improves the fuel properties of horse chestnuts, oak acorns, and spruce cones. The properties of torrefied biomass at 320 °C were very similar to hard coal. In the case of horse chestnuts, an increase in fixed carbon content from 18.1% to 44.7%, and a decrease in volatiles from 82.9% to 59.8% were determined. Additionally, torrefied materials were characterized by their hydrophobic properties. In terms of energy yield, the highest value was achieved for oak acorns torrefied at 280 °C and amounted to 1.25. Moreover, higher heating value for the investigated forestry fruit residues ranged from 24.5 MJ·kg−1 to almost 27.0 MJ·kg−1 (at a torrefaction temperature of 320 °C).

scholarly journals Locating the “Local” in Peacebuilding

2021 ◽  
Author(s):  
Brandon Kendhammer ◽  
Wyatt Chandler
Keyword(s):  
Literature Review ◽  
National Level ◽  
Sub Saharan Africa ◽  
Extensive Literature ◽  
Post Conflict ◽  
Wide Range ◽  
Local Actors ◽  
International Donors ◽  
Sub Saharan ◽  
Subnational Conflict

Drawing on an extensive literature review and four case studies from leading examples of post-conflict local peacebuilding in sub-Saharan Africa, this report argues that the “local” in local peacebuilding is best defined as local knowledge of conflict drivers and dynamics and locally defined, contextually specific definitions of peace. This does not necessarily mean working through or empowering “traditional” actors and institutions (a highly contested category, in any case). Nor should it mean a narrow focus on subnational conflict drivers and peace actors to the detriment of assessing how national and international dynamics shape local peace challenges (and vice versa). International donors and peace actors are most successful when they operate with a keen awareness that all potential peacebuilding actors (national and local actors, but also external donors, "experts," and implementers) have their own agendas and that peacebuilding efforts that work at the sub-national level and engage local actors are not automatically endowed with legitimacy and community buy-in just because of their "localness." International actors must also be flexible and open to partnering with a wide range of local actors, including those that don’t meet preconceived international expectations about what an effective local partner looks like (often, old, male, and "traditional").

Transient Performance Analysis of an Industrial Gas Turbine Operating on Low-Calorific Fuels

2016 ◽  
Vol 139 (5) ◽  
Author(s):  
Vrishika Singh ◽  
Lars-Uno Axelsson ◽  
W.P.J. Visser
Keyword(s):  
Steady State ◽  
Energy Density ◽  
Gas Turbine ◽  
Alternative Fuels ◽  
Combustion Process ◽  
Transient Behavior ◽  
Performance Model ◽  
Transient Performance ◽  
Wide Range ◽  
Industrial Gas Turbine

The demand for more environmentally friendly and economic power production has led to an increasing interest to utilize alternative fuels. In the past, several investigations focusing on the effect of low-calorific fuels on the combustion process and steady-state performance have been published. However, it is also important to consider the transient behavior of the gas turbine when operating on nonconventional fuels. The alternative fuels contain very often a large amount of dilutants resulting in a low energy density. Therefore, a higher fuel flow rate is required, which can impact the dynamic behavior of the gas turbine. This paper will present an investigation of the transient behavior of the all-radial OP16 gas turbine. The OP16 is an industrial gas turbine rated at 1.9 MW, which has the capability to burn a wide range of fuels including ultra-low-calorific gaseous fuels. The transient behavior is simulated using the commercial software GSP including the recently added thermal network modeling functionality. The steady-state and transient performance model is thoroughly validated using real engine test data. The developed model is used to simulate and analyze the physical behavior of the gas turbine when performing load sheds. From the simulations, it is found that the energy density of the fuel has a noticeable effect on the rotor over-speed and must be considered when designing the fuel control.

FMM/GPU Accelerated BEM Simulations of Emulsion Flow in Microchannels

2013 ◽  
Author(s):  
Olga A. Abramova ◽  
Yulia A. Itkulova ◽  
Nail A. Gumerov
Keyword(s):  
Oil Recovery ◽  
Large Scale ◽  
Heterogeneous Computing ◽  
Three Dimensional ◽  
Industrial Applications ◽  
Computational Techniques ◽  
Graphics Processors ◽  
Two Phase ◽  
Scalable Algorithm ◽  
Wide Range

Modeling of motion of two-phase liquids in microchannels of different shape is needed for a variety of industrial applications, such as enhanced oil recovery, advanced material processing, and biotechnology. Development of efficient computational techniques is required for understanding the mechanisms of many effects in “liquid-liquid” systems, such as the jamming of emulsion flows in microchannels and blood cell motion in capillaries. In the present study, a mathematical model of a three-dimensional flow of a mixture of two Newtonian liquids of a droplet structure in microchannels at low Reynold’s numbers is considered. The computational approach is based on the boundary element method accelerated both via an advanced scalable algorithm (FMM), and via utilization of a heterogeneous computing architecture (multicore CPUs and graphics processors). To solve large scale problems flexible GMRES solver is developed. Example computations are conducted for dynamics of many deformable drops of different sizes in microchannels. The results of simulations and accuracy/performance of the method are discussed. The developed approach can be used for solution of a wide range of problems related to emulsion flows in micro- and nanoscales.

Transient Performance Analysis of an Industrial Gas Turbine Operating on Low-Calorific Fuels

2016 ◽  
Author(s):  
Vrishika Singh ◽  
Lars-Uno Axelsson ◽  
W. P. J. Visser
Keyword(s):  
Steady State ◽  
Energy Density ◽  
Gas Turbine ◽  
Alternative Fuels ◽  
Combustion Process ◽  
Transient Behavior ◽  
Performance Model ◽  
Transient Performance ◽  
Wide Range ◽  
Industrial Gas Turbine

The demand for more environmentally friendly and economic power production has led to an increasing interest to utilize alternative fuels. In the past, several investigations focusing on the effect of low-calorific fuels on the combustion process and steady-state performance have been published. However, it is also important to consider the transient behavior of the gas turbine when operating on non-conventional fuels. The alternative fuels contain very often a large amount of dilutants resulting in a low energy density. Therefore a higher fuel flow rate is required, which can impact the dynamic behavior of the gas turbine. This paper will present an investigation of the transient behavior of the all-radial OP16 gas turbine. The OP16 is an industrial gas turbine rated at 1.9 MW, which has the capability to burn a wide range of fuels including ultra-low-calorific gaseous fuels. The transient behavior is simulated using the commercial software GSP including the recently added thermal network modeling functionality. The steady-state and transient performance model is thoroughly validated using real engine test data. The developed model is used to simulate and analyze the physical behavior of the gas turbine when performing load sheds. From the simulations it is found that the energy density of the fuel has a noticeable effect of the rotor over-speed and must be considered when designing the fuel control.

The Destruction of Exergy During the Combustion Process for a Spark-Ignition Engine

2010 ◽  
Author(s):  
Jerald A. Caton
Keyword(s):  
Internal Combustion Engine ◽  
Combustion Engine ◽  
Combustion Process ◽  
Internal Combustion ◽  
Spark Ignition ◽  
Spark Ignition Engine ◽  
Design Parameters ◽  
Base Case ◽  
Operating Parameters ◽  
Wide Range

The second law of thermodynamics provides the mechanism for assessing the quality of energy. The non-conserved property used for this assessment is called exergy, availability or available energy. For the internal combustion engine, the exergy of the fuel is distributed among work, heat transfer, exhaust, and is destroyed by several processes. The major destruction of exergy for the internal combustion engine is during the combustion process. This paper documents this destruction for a wide range of engine operating parameters, design parameters, and fuels. A 5.7 liter, spark ignition, automotive engine was selected for this study. Operating parameters that were examined included equivalence ratio, speed, load and spark timing. Design parameters that were examined included compression ratio, expansion ratio and the use of turbocharging. Combustion parameters and oxidizer were examined as well. The fuels examined included isooctane (base), methane, propane, hexane, methanol, ethanol, hydrogen and carbon monoxide. For the part load base case (1400 rpm and a bmep of 325 kPa) using isooctane, the destruction of exergy was 21% of the fuel exergy. For many of the engine operating and design parameters, this destruction was relatively constant (between about 20 and 23%). The parameters that resulted in the greatest change of the exergy destruction were (1) exhaust gas recirculation, and (2) inlet oxygen concentration. In general, the amount of the destruction of exergy during the combustion processes was associated with the level of the combustion temperatures.

scholarly journals Development of mathematical model for co-firing pulverized coal and biomass in experimental furnace

2018 ◽  
Vol 22 (1 Part B) ◽  
pp. 709-719 ◽  
Author(s):  
Aleksandar Milicevic ◽  
Srdjan Belosevic ◽  
Ivan Tomanovic ◽  
Nenad Crnomarkovic ◽  
Dragan Tucakovic
Keyword(s):  
Mathematical Model ◽  
Turbulent Transport ◽  
Combustion Process ◽  
Computer Code ◽  
Transport Processes ◽  
Pulverized Coal ◽  
Combustion Model ◽  
Two Phase ◽  
Processes And Reactions ◽  
Wide Range

A comprehensive mathematical model for prediction of turbulent transport processes and reactions during co-combustion of pulverized fuels in furnace fired by 150 kW swirl stabilized-burner has been developed. Numerical simulations have been carried out by using an in-house developed computer code, with Euler-Lagrangian approach to the two-phase flow modelling and sub-models for individual phases during complex combustion process: evaporation, devolatilization, combustion of volatiles, and char combustion. For sub-model of coal devolatilization the approach of Merrick is adopted, while for biomass devolatilization the combination models of Merrick, and of Xu and Tomita are selected. Products of devolatilization of both the pulverized coal and biomass are considered to contain the primary gaseous volatiles and tar, which further decomposes to secondary gaseous volatiles and residual soot. The residual soot in tar and carbon in coal and biomass char are oxidized directly, with ash remaining. For volatiles combustion the finite rate/eddy break-up model is chosen, while for char oxidation the combined kinetic-diffusion model is used. The comprehensive combustion model is validated against available experimental data from the case-study cylindrical furnace. The agreement of the simulations with the data for the main species in the furnace is quite good, while some discrepancies from experimental values are found in the core zone. The presented model is a good basis for further research of co-combustion processes and is able to provide analysis of wide range of pulverized fuels, i. e. coal and biomass. At the same time, the model is relatively simple numerical tool for effective and practical use.

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