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Show The B ERL has the potential to generate an enormous and overwhelming data base. However, by limiting the program to a few welldefined objectives it will accomplish the following: • Characterize a single baseline burner and thereby establish the range of diagnostics available in the facili ty. • Establish criteria for future evaluation of industrial burners. • Demonstrate the current ability and the potential for application of advanced diagnostics to the study of practical combustion devices. • Observe and document phenomena which previously have been unknown in practical combustors. • Identify scaling laws which can aid in the design of large-scale industrial combustors. During the demonstration phase of the BERL the primary objective will be to establish the system reliability and performance specifications. The ultimate goal of this program is the creation of a laboratory to conduct fundamental research that improves the effectiveness of natural gas use in burners. Effectiveness is a SUbjective term, it implies that the burner is part of a system. This system dictates the requirements against which effectiveness can be measured. For instance, a burner operating without an enclosure may be considered extremely effective if it is quiet; on the other hand, this same burner could be extremely ineffective if precise control of the flame length is important rather than noise. Thus, effectiveness depends upon application. A burner is not just a device for producing a stable flame. It is a device which allows chemical energy to be converted to thermal energy under conditions specified by particular needs. Gas burners may be premixed or diffusion burners (fuel and air supplied separately). They may operate in the laminar or turbulent flow regime. They may be designed to fire in the open air or in highly confined hot wall enclosures and they can range in capacity 3 from watts to many megawatts. It is not the intent of this program to create a laboratory capable of investigating such a diverse range of applications, but to allow fundamental studies which concentrate upon the major features of all natural gas burners. The designer of industrial equipment may define burner effectiveness as: • flame stability over the required flow range • pollutant emissions which meet specifications • heat release profiling to match process requirements • ease of ignition • minimum production costs Fundamental studies are not meant to replace development activities. Their function is to generate understanding which can the be translated into a device by the development engineer. The BERL should be concerned with the fundamentals of flame stability, pollutant formation, heat release rate, radiation transfer and noise generation under typical conditions. The ability to transfer this information from research scientist to development engineer quite often depends upon the availability of models which are developed and validated in the research laboratory. Models of burner flames require an understanding of complex chemistry and physics which occurs in turbulent reacting flows. The B ERL is intended to satisfy two basic needs: • The generation of benchmark data to characterize the stability, heat release mechanism and pollutant formation in natural gas flames. These data will be used to assess model development and evaluate combustion theories. Thus, the laboratory must be able to generate data to a well defined protocol which allows all relevant boundary conditions to be specified accurately. |