Energy Conversion最新文献

{"title":"Numerical Simulation of Combustion Air Systems for Large Industrial Boilers","authors":"K. Jorgensen, R. A. Wessel, J. R. Strempek","doi":"10.1115/IMECE2002-39295","DOIUrl":"https://doi.org/10.1115/IMECE2002-39295","url":null,"abstract":"Combustion air systems are an important aspect of the performance of industrial boilers and are increasingly being used as an integral means of reducing emissions. With the wide range of unique air system designs presently deployed, traditional methods of analyzing performance, based on experience, have become more difficult and less reliable. Numerical simulations are currently being used as a tool to analyze the operation and design of these air systems and how they relate to boiler performance and emission control. A proprietary CFD combustion code has been applied to a wide range of industrial boilers. Recent results from three selected studies are presented. These case studies demonstrate the benefits of using numerical simulation to: 1) analyze and optimize an existing air system, 2) validate an upgrade design, and 3) design and develop a new air system concept.© 2002 ASME","PeriodicalId":100466,"journal":{"name":"Energy Conversion","volume":"25 1","pages":"9-16"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82443936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Particle Size on Pipeline Flow of Solid-Liquid Slurry With Fixed Particle Size Distribution","authors":"P. Skudarnov, M. Daas, Cheng-Xian Lin, M. Ebadian, P. W. Gibbons, F. Erian, M. Rinker","doi":"10.1115/IMECE2002-39310","DOIUrl":"https://doi.org/10.1115/IMECE2002-39310","url":null,"abstract":"The transport properties of solid-liquid slurries having the same well-defined particle size distribution but different median particle sizes have been studied in a 22-mm I.D. horizontal pipeline flow loop. The solid-liquid slurries were glass beads-water mixtures. The particle size distribution of solids was Rosin-Rammler with median diameters of 50 mm and 250 mm. The relationship between the pressure drop in the straight horizontal sections of the flow loop and the mean slurry velocity was determined for different solids volume concentrations varying from 4.5 to 25% and mean slurry velocity ranging from 0.5 to 2.5 m/s. Critical deposition velocity was measured from visual observations. An existing empirical model of Wasp et al. that predicts the pressure gradient for a single-species slurry flow in a horizontal pipeline was used to describe the pressure drop data. The Oroskar-Turian correlation for critical velocity was used for comparison with the measured critical velocities.Copyright © 2002 by ASME","PeriodicalId":100466,"journal":{"name":"Energy Conversion","volume":"39 1","pages":"103-108"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83187780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimation of Gas and Liquid Flow Rates in Gas-Liquid Two-Phase System","authors":"K. Mori, Tetsumasa Ono, M. Kaji, T. Sawai","doi":"10.1115/IMECE2002-39311","DOIUrl":"https://doi.org/10.1115/IMECE2002-39311","url":null,"abstract":"A new method of estimating gas and liquid flow rates is proposed for a gas-liquid two-phase flow system. The method involves measurement of pressure drops in horizontal and vertical flow channels, and calculation of flow rates by Lockhart-Martinelli correlation. The method does not require the insertion of sensing device into the flow channel and does not rely on previously calibrated correlations. Experiments are performed in slug, froth and annular flow regimes for an air-water system, and the usefulness of the proposed method is examined. The results reveal that gas and liquid flow rates can be estimated with the accuracies of 45% for gas phase and 37% for liquid phase with respect to mean values.© 2002 ASME","PeriodicalId":100466,"journal":{"name":"Energy Conversion","volume":"1 1","pages":"109-113"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79950644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Schlieren and Shadowgraph Images of Transient Expanding Spherical Thin Flames","authors":"Matyas Matlo, F. Parsinejad, H. Metghalchi","doi":"10.1115/IMECE2002-39318","DOIUrl":"https://doi.org/10.1115/IMECE2002-39318","url":null,"abstract":"Experimental facilities have been built to visualize transient expanding spherical flames. Facilities include a cylindrical chamber with two end glasses for optical observation. Shadowgraph and Schlieren pictures of flame propagation have been taken using a high speed Charged Coupled Device (CCD) camera. In this paper the optical behavior of spherical flames has been investigated using both Schlieren and Shadowgraph methods. A mathematical model has been developed to predict the intensity of refracted light beams interacting with a transient expanding thin flame. Experimental results are in very good agreement with theoretical model. Schlieren and Shadowgraph techniques have also been used to view smooth, cracked and cellular flames, which are useful in determining the stability of propagating flame.Copyright © 2002 by ASME","PeriodicalId":100466,"journal":{"name":"Energy Conversion","volume":"26 1","pages":"71-76"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91218441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a Monitoring System for Near Burner Slag Formation","authors":"C. K. Tan, S. Wilcox, J. Ward","doi":"10.1115/IMECE2002-39300","DOIUrl":"https://doi.org/10.1115/IMECE2002-39300","url":null,"abstract":"A series of experiments on two different coals at a range of burner conditions have been conducted to investigate the behaviour of pf coal combustion on a 150kW pulverised fuel (pf) coal burner with a simulated eyebrow (a growth of slag in the near burner region). The simulation of a burner eyebrow was achieved by inserting an annulus of refractory material immediately in front of the face of the original burner quarl. Results obtained from monitoring the infrared (IR) radiation and sound emitted by the flame were processed into a number of features which were then used to train and test a self organising map neural network. Results obtained from the neural network demonstrated a classification success, never lower than 99.3%, indicate that it is not only possible to detect the presence of an eyebrow by monitoring the flame, but it is also possible to give an indication as to its size, over a reasonably large range of conditions.© 2002 ASME","PeriodicalId":100466,"journal":{"name":"Energy Conversion","volume":"1 1","pages":"63-69"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91142693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Intermittent Sprays","authors":"B. Jawad","doi":"10.1115/IMECE2002-39319","DOIUrl":"https://doi.org/10.1115/IMECE2002-39319","url":null,"abstract":"The purpose of this study is to gain further insight into the atomization mechanism, the variation over time in droplet size distribution and spray penetration. This is done based on effect of chamber pressure, injection pressure, and type of fuel. A laser diffraction method is used to determine droplet mean diameters, single injection with synchronized time mechanism allowed the time dependent studies. Obscuration signals are obtained through a digital oscilloscope from which arrival time of spray can be measured. The spray penetration correlation obtained is compared to other correlations obtained from other techniques used in the literature.Copyright © 2002 by ASME","PeriodicalId":100466,"journal":{"name":"Energy Conversion","volume":"62 1","pages":"77-85"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78130914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mixing and Combustion Improvement Using Jet Injection Into Swirling Flowfields","authors":"D. Lilley","doi":"10.1115/IMECE2002-39600","DOIUrl":"https://doi.org/10.1115/IMECE2002-39600","url":null,"abstract":"The aerodynamics benefits of lateral jet injection into swirling crossflow have long been recognized and used by combustion engineers. Studies are reported here on experimental and theoretical research on lateral jet injection into typical combustor flowfields for low-speed turbulent swirling flow conditions in the absence of combustion. The main flow is air in a round cross-sectioned plexiglass tube. The degree of swirl can be varied by varying the angles of the blades of an annular swirler, located upstream of the test section. Lateral jet injection is normal to the main airflow, from round-sectioned nozzles. Either a single lateral jet or two diametrically opposed jets are used for this secondary injection of air into the main airflow. The principal aim is to investigate the trajectory, penetration and mixing efficiency of the lateral injection. Flow visualization with helium-filled soap bubbles and multi-spark ionized path techniques, five-hole pitot probe time-mean velocity measurements, and single-wire time-mean velocity and turbulence data (normal and shear stress) have been obtained in the experimental research program. A fully three-dimensional computer code with two-equation turbulence model has been developed and used in the theoretical research program.Copyright © 2002 by ASME","PeriodicalId":100466,"journal":{"name":"Energy Conversion","volume":"48 1","pages":"55-62"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88205610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Study of Operability of Combustor With Inflow Oscillations","authors":"K. Su, Chenn Q. Zhou","doi":"10.1115/IMECE2002-39294","DOIUrl":"https://doi.org/10.1115/IMECE2002-39294","url":null,"abstract":"Numerical study of gas turbine combustion with the inflow oscillation has been conducted using KIVA-3V code. The simulation was based on the solution of Navier-Stokes equations with a time-marching method and models of turbulence and sprays, and a simplified kinetic mechanism of 17-species and 23-step. The transient inflow was assumed by specifying the pressure oscillation in a form of sinusoidal function. Effects of three flow patterns, i.e. quasi-steady, transition and steady patterns corresponding to the oscillation frequency ranges of n ≤ 80, 80 ≤ n ≤ 320 and n ≥ 320 Hz, on combustion performance were investigated. It is found that for the flow in quasi-steady pattern, combustion is in quasi-steady state with flow and combustion properties dependent of time and the analytical approaches for steady combustion can be applied; for the flow in steady pattern, combustion can be treated as if in steady state and the influence of oscillation can be ignored; and in transition pattern, the combustion behaves in-between. Finally, the operability of combustor with inflow oscillation was analyzed, which is useful for the analysis of combustion performance under irregular inflow conditions.Copyright © 2002 by ASME","PeriodicalId":100466,"journal":{"name":"Energy Conversion","volume":"88 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82344282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the Mathematical Modeling of Heat Transfer Characteristics of Turbulent Flames in Industrial Furnaces","authors":"E. Khalil","doi":"10.1115/IMECE2002-39296","DOIUrl":"https://doi.org/10.1115/IMECE2002-39296","url":null,"abstract":"The recent advances in numerical methods and the vast development of computers had directed the designers to better development and modifications to air flow pattern and heat transfer in combustion chambers. Extensive efforts are exerted to adequately predict the air velocity and turbulence intensity distributions in the combustor zones and to reduce the emitted pollution and noise abatement to ultimately produce quite and energy efficient combustor systems. The present work fosters mathematical modeling techniques to primarily predict what happens in three-dimensional combustion chambers simulating boiler furnaces, areo engines in terms of flow regimes and interactions. The present work also demonstrates the effect of chamber design and operational parameters on performance, wall heat transfer under various operating parameters. The governing equations of mass, momentum and energy are commonly expressed in a preset form with source terms to represent pressure gradients, turbulence and viscous action. The physical and chemical characteristics of the air and fuel are obtained from tabulated data in the literature. The flow regimes and heat transfer play an important role in the efficiency and utilization of energy. The results are obtained in this work with the aid of the three-dimensional program 3DCOMB; applied to axisymmetrical and three-dimensional complex geometry with and without swirl with liquid or gaseous fuels. The present numerical grid arrangements cover the combustion chamber in the X, R or Y and Z coordinates directions. The numerical residual in the governing equations is typically less than 0.001%. The obtained results include velocity vectors, turbulence intensities and wall heat transfer distributions in combusors. Examples of large industrial furnaces are shown and are in good agreement with available measurements in the open literature. One may conclude that flow patterns, turbulence and heat transfer in combustors are strongly affected by the inlet swirl, inlet momentum ratios, combustor geometry. Both micro and macro mixing levels are influential. The present modeling capabilities can adequately predict the local flow pattern and heat transfer characteristics in Complex combustors. Proper representation of the heat transfer and radiation flux is important in adequate predictions of large furnace performance.Copyright © 2002 by ASME","PeriodicalId":100466,"journal":{"name":"Energy Conversion","volume":"78 11 1","pages":"17-27"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87906147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Application of a Two-Dimensional Zone Model to the Design and Control of a Continuously Operated, Gas-Fired Furnace","authors":"Sara A. C. Correia, J. Ward","doi":"10.1115/IMECE2002-39297","DOIUrl":"https://doi.org/10.1115/IMECE2002-39297","url":null,"abstract":"This paper describes the development of a two-dimensional zone model to predict the throughput and thermal performance of a continuously operated gas-fired furnace heating steel bars to a nominal discharge temperature of 1250°C. Ultimately the model is intended to be a tool which can be used for the design and control of industrial furnaces. Consequently relatively short computing times are necessary and this was achieved by employing an isothermal computational fluid dynamics simulation to estimate the relative mass flows, and hence enthalpy flows to or from adjacent volume zones in the overall model. This simplified approach, which utilises a single “once off” isothermal computation of the flows, was considered to be adequate since isothermal flow models have been used successfully in the past to study the flow related behaviour of combustion systems. The coupling of a multi-zone model with a single “once off” isothermal computation of the flows enables a wide range of furnace design modifications to be studied quickly and easily. To illustrate the potential use of the model in a furnace design application, it was then used to investigate the effects of inclining the burners downwards towards the load as well as those associated with increasing the length of the furnace.Copyright © 2002 by ASME","PeriodicalId":100466,"journal":{"name":"Energy Conversion","volume":"3 1","pages":"29-35"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81921461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}