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Among other products made at its plant in Rheinfelden, Evonik manufactures AEROSIL®, which is used in many everyday products such as toothpaste, paints and coatings, and LED lamps. AEROSIL® improves the properties of these products and in many cases makes them more energy-efficient, e.g. as a component of heat-insulating refrigerator doors. AEROSIL® is a white powder and chemically speaking a kind of sand that is produced in a combustion process. This fumed silica is produced from hydrogen, the chemical compound chlorosilane and dehumidified air. Previously, Evonik produced the hydrogen needed for this process using natural gas in the so-called steam reforming process. However, this gives rise to specific CO2 emissions.

Decoupling is an important link in the control of combustion process of circulating fluidized bed boiler (CFBB). In this paper, the method of fuzzy is used in decoupling process, and the fuzzy decoupling device is designed based on the model of object with certain load. Then the control effect is compared with the simulation result which without decoupling device, and the contrast results showed that the method has a good decoupling capability. The method is easy to realize and simple to design, besides it has a good characteristics in adjusting the object model, it is valuable in the actual industry.

Regarding the power, the efficiency and the emission of the low speed diesel engine, this paper has studied the matching and optimizing technique in the diesel engine combustion process emphatically, proposed the electrically controlled fuel injecting system with the high-pressured common rail as well as the humid air motor method and the system plan. The practice proved that the fuel injecting system with the high-pressured common rail and the humid air motor system can improve the combustion process most efficiently, thus enhance the diesel engine’s performance, and reduce the pollutant discharge.

The use of simulation tools such as CFD leads to a detailed fundamental understanding of the complex processes during coal combustion. Thus, mathematical modeling provides an important instrument for research and development of the oxy-coal combustion technology which represents one of the promising CO2 capture and storage (CCS) technologies. In this process, coal is burnt in an atmosphere consisting of pure O2 mixed with recycled flue gas leading to an exhaust gas with high CO2 concentration which is ready for storage after further conditioning. However, the specific conditions of the oxy-coal combustion process require several adjustments in the CFD code which was originally been developed for conventional air-firing combustion. Accordingly, advanced sub-models concerning global homogeneous and heterogeneous chemistry as well as gas phase radiation have been developed and implemented in IFK’s CFD code AIOLOS.

In order to overcome the noise caused influence on the result of neutral network training, the paper introduces the RANSAC algorithm into the neutral network training and puts forward a RANSAC-BP neutral network training algorithm. In this algorithm a t-distribution based confidence interval is constructed to replace the distance threshold, which overcomes the weakness that the threshold selection in the neutral network training has to rely on experience; the algorithm culls noisy data during neutral network training and then re-train the neutral network with noise free data, thus making the neutral network training algorithm less sensitive to data noises. This algorithm has been validated by a simulation experiment. At the phase of model analysis, taking the optimal working conditions as the reference points, the paper takes the partial differential of the function (the relation between inputs and outputs, trained through RANSCK-BP) as the transfer function, which portrays how the small changes in the input parameters influence the output parameters. This provides a method to analyze the sensitivity of the combustion optimization model.

In actual operating spaces encumbered with technical tools and equipment there is a possibility of filling them with combustible mixtures. As a rule, feedback mechanisms providing interaction between flame/initial mixture motion and compression waves generated during the combustion process are possible and exist in reactive mixtures. Below are some known examples of such mechanisms [1]

According to the characteristics of boiler combustion process, we use image processing technique to extract features that characterize the features of flame. On requirements of good real-time performance boiler burning diagnose system, we develop a set of PC add DSP real-time image acquisition and burning diagnosis system on the 200MW boilers. The results show that the system is simple, practical, and can realize combustion diagnosis in the boiler operation process. The system provides a reliable basis for the safety of the power station boilers and economic operation, and has certain engineering application prospects.

Tracking features and exploring their temporal dynamics can aid scientists in identifying interesting time intervals in a simulation and serve as basis for performing quantitative analyses of temporal phenomena. In this paper, we develop a novel approach for tracking subsets of isosurfaces, such as burning regions in simulated flames, which are defined as areas of high fuel consumption on a temperature isosurface. Tracking such regions as they merge and split over time can provide important insights into the impact of turbulence on the combustion process. However, the convoluted nature of the temperature isosurface and its rapid movement make this analysis particularly challenging.

The article presents the results of experimental studies conducted on a large-scale 235 MWe CFB (Circulating Fluidized Bed) boiler, in which the primary air distribution system was modified. The modification was connected with the change of internal geometry of primary air channels as well as internal space of plenum chamber. The obtained results have shown, that the optimization of primary air flow has a great influence on the intensity of the combustion process and the temperature distribution along the height of combustion chamber. As a result, the NOx emission has been reduced by up to ten percent and the temperature profile in the combustion chamber has been revealed to be more uniform.

In this chapter, combustion process is improved by computing control settings with clustering algorithms. The framework involves learning from a high-dimensional data stream generated by the combustion process. Thus the system's dynamics is captured. The concepts of virtual age of the boiler and the control settings are introduced. The confidence of applying a control setting to improve boiler performance is quantified. The framework is easy to implement and it handles a large number of process variables. The ideas introduced in this paper have been implemented at a 20 MW boiler controlled with a standard control system. That system makes run-time recommendations to the standard control system.

Even though China has built several kinds of BBDF machine and burning equipments which established the base for BBDF industrialization, there are still several difficulties faced by Chinese scholars. Some of them are biomass gathering, mechanical abrasion of the equipment in briquetting process and sediment of clinker, and cauterization of the hearth in combustion process,which greatly limit the development of BBDF industry. Thus, this paper argues that the difficulties should be solved within BBDF technology research and application in actual engineering. Moreover, the application status of BBDF technology was addressed and analyzed in this paper. By summing up the successful and the failing experiences, some methods to deal with the difficulties are recommended and a proposal of BBDF development model in China was also provided.

Modern engines are complex mechatronic systems and require periodic maintenances during whole lifecycle. In present time mobile diagnostic methods are very effective tools applicable for all combustion engines. This paper deals with an out of montage diagnostic of internal combustion engines. Principles of the diagnostic method are based on sound evaluation of a running engine. This method can control dysfunctions in mechanical and thermodynamic side of the engine

The article presents an optimization method of combustion process in a power boiler. This solution is based on the artificial immune systems theory. A layered optimization system is used, to minimize CO and NOx emission. Immune inspired optimizer SILO is implemented in each of three units of Ostroleka Power Plant (Poland). The results from this implementation are presented. They confirm that presented solution is effective and usable in practice.

Monitoring the combustion process for electricity generation using coal as a primary resource is of a major concern to the pertinent industries, power generation companies in particular. The carbon content of fly ash is indicative of the combustion efficiency. The determination of this parameter is useful to characterise the efficiency of coal burning furnaces. Traditional methods such as Thermogrametric Analysis (TGA) and Loss on Ignition which are based on ash collection and subsequent analysis, proved to be tediously difficult, time consuming and costly. Thus, a need for a new technology was inevitable and needed to monitor the process in a more efficient method yielding a better exploitation of the resources at a lower cost. The main aim of this work is to introduce a new automated system which can be bolted onto a furnace and work online. The system consists of three main components, namely, a laser instrument for signal acquisition, a neural network tool for training, learning and simulation, and a database system for storage and retrieval. The components have been designed, adapted and tuned for knowledge acquisition of this multidimensional problem. The system has been tested for a range of coal ashes and proved to be efficient.

A classification of combustion processes is presented which can be used for discussing influences of microgravity. Profound effects of gravity on combustion arise from the large fractional density changes that generally are associated with combustion. thus it seems to be rather the rule than the exception that combustion experiments under microgravity conditions reveal previously unanticipated phenomena. A few of these phenomena and their theoretical explanations are presented here. Particular attention is devoted to flame balls and to alcohol droplet combustion. Some accomplishments of these and other microgravity combustion studies are summarized. Finally, combustion topics which appear to hold greatest promise for benefiting from future microgravity experiments are indicated.

Under the background of HUADIAN oil shale synthetic utilization project in china, oil shale from HUADIAN were pyrolyzed simulating Brazil PETROSIX technology and semi-coke samples were obtained. In this research, combustion of the bl-ends between oil shale(OS) and OS semicoke(SC) mixture were initially investigated in TGA. From the TGA experiments, three main different reaction regions were observed for most of the samples. Furthermore, a fluidized bed reactor was established and the related fluidized combustion experiments of the blends were performed. It was observed that many factors, such as bed temperature, apparent fluidized velocity, individual weights of the blends, ejected total weight, and the particle size had effect on burnout time. The results showed that burnout time was fairly linear with particle size, which indicated that chemical kinetics, rather than diffusion, significantly influenced the combustion process. The research may provide theoretical foundation for further effective exploitation and economical application of oil shale and semicoke.

The D.I. Diesel engine injection strategies give special importance to the processes of spray penetration and mixture formation in the combustion chamber, because of their important role on soot and NOx formation. The purpose of this paper is to clarify in some way the influence of injection strategies by combination of optical diagnostics such as Laser Induced Exciplex Fluorescence technique (LIEF) and natural flame emission in a transparent D.I. Diesel engine of the production size. The influence of engine operating conditions, which are the presence of a pre-injection and swirl number is studied. Measurement of the injection rate and injected individual quantities is yield, then spray development is studied in the engine environment. Finally, by recording intensified pictures of the first reaction zones, it is shown how swirl intensification could influence the start of combustion.

The present work reports on the application of optical measurement-techniques to combustion-processes as they are investigated at the “Lehrstuhl A fur Thermodynamik ” of the “Technische Universitat Munchen”. The outstanding characteristics of the optical measurementtechniques in combustion research are described, and their potentials for the determination of important process-variables are explained with applications of various kinds, which cover the range from explosions up to transient supersonic combustion.

The tasks of air pollution control in the different emission source areas of traffic,industrial processes and industrial furnaces as well as domestic heating systems are manifold. Basically, emission reductions are possible by changing to lower-emission processes or low-emission fuels, improving the process, e.g., the combustion process: primary prevention measures, exhaust gas purification: secondary measures.

The most important anthropogenic source groups of air pollution are industrial furnaces and industrial processes, traffic, small-scale businesses and domestic furnaces as well as special sources such as animal confinement systems, spray cans etc.

The free radicals which provided the impetus for life’s beginning also damage the same biomolecules that they helped to originate. Biological life is a combustion process which needs oxygen, but it is also endangered by reactive oxygen metabolites, so-called reactive oxygen species. It was suggested by Harman that life originated as a result of free radical reactions, selected free radical reactions to play a major part in metabolism, and assured evolution by employing them to provide for mutation and death (Harman 1984). The historical roots of the concept of oxidative injury in biological systems, and particularly in dermatopathology, are heterogeneous.

Flames embody an array of highly complex physico-chemical phenomena. Their complexity is, in part, a consequence of fluid dynamical and other instabilities which render them prone to irregular behavior, or at least to complicated patterns in space-time. Another complexity is due to the large number of chemical reactions which nearly always contribute to the combustion process. Both of these difficulties are often ignored in analytical treatments, although some major advances achieved in the last decade have served to clarify a few issues in the first category. There have also been analyses illustrating the effects which multiple reactions may have on flames (e.g., see [5], [6], [7], [8], and [9], and related issues in [1]).

The key to the understanding of his general mode of proceeding lies in a more or less casual remark of Mayer’s in a letter to his friend Carl Baur from July 24th 18411. Here he speaks of a “System of Physics” which he has brought back with him from a voyage to the East Indies. This might sound somewhat conceited for a young doctor with scanty knowledge of physics, were it not for Mayer’s almost proverbial modesty. Yet exactly this non-professionalism is a necessary condition for his further investigations, as he discloses the gaps in established science, without deformation professionelle, and on the other hand is compelled to become acquainted with doctrinal physics well enough to be able, if necessary, to recognize his new ideas as chimeras. His point of departure “from physical and pathological investigations” is thereby not so much his oft-quoted discovery of bright red veinous blood, and his (in fact incorrect) explanation whereafter the reduced loss of heat in the human body in the tropics effects a lowered combustion process in the blood, but the clearly stated question “Can the mechanical effect produced in the animal by the expenditure of combustion develop or not?”2. His intention to answer this question for physiology leads Mayer into physics without constraint.

A hybrid rocket is so named because one of the propellant components is liquid and the other solid. Normally the oxidizer is liquid and the fuel is solid. In a typical design (Fig. 7-1), the oxidizer is sprayed in at the head end of a solid cylindrical fuel grain. It is apparent that once the liquid oxidizer is injected, the combustion process proceeds according to natural law and the geometric constraints designed into the grain and is not subject to external control. It is very important, therefore, to understand the details of the combustion if it is to occur in the manner desired by the designer.