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Show UPDATED DEVELOPMENT PLANS After completion of Component Defmition, the design of a full-scale (350 MW J fully integrated LEBS Commercial Generating Unit was developed. Based on the information gained during the Component Definition activities, and along with the Commercial Generating Unit Design, the Design Deficiency Analysis and the Research, Development, and Test Plan were re-evaluated and updated. The activities described in the updated RD&T Plan were to be carried out in Phases II, ill & IV. PHASE II DEVELOPMENT ACTIVITIES Based on the decision not to proceed with the MIT-RSFC burner, Phase II began with further development of the advanced 10w-NOx burner. Concurrently to the LEBS program, B&W was developing an advanced 10w-NOx burner through an internally funded program. Initial results of this internally funded program looked promising, therefore, the burner concept developed in this program was determined to be a starting basis for the LEBS advanced 10w-NOx burner development. Through engineering analysis, a list of configuration variations were developed. From this list, the configurations with the greatest potential for improvement were chosen. Numerical modeling and pilot-scale testing were used concurrently through the burner development activities in Phase II. Starting with the existing advanced 10w-NOx burner concept, modeling was used to evaluate concept variations which would be expensive to build and test. These variations included changes in the number of burner air zones, zone areas and velocities, and flow splits. Parallel with this modeling effort, pilot-scale testing was used to investigate parameters that could be more efficiently evaluated with experimental test on the 5 MBtulhr scale. These included burner air swirl, air/coal ratio, and burner stoichiometry. In addition, pilot-scale testing was used to further evaluate key burner concepts identified with numerical modeling. Results from these tests were then fed back to additional model studies. This provided an efficient means to evaluate and revise likely burner concepts. Evaluations were completed using both two-dimensional (2-D) and three-dimensional (3-D) numerical flow and combustion models. Two-dimensional axisymmetric modeling was used to parametrically evaluate a range of burner configurations with faster turn-around time than would be possible with full 3-D models. An example of a typical 2-D prediction for a burner concept is shown in Figure 10. Such models proved useful to qualitatively evaluate the effect of burner design variations on fuel penetration and mixing, internal and external recirculation zones, flame shape, and near-burner temperatures. Final 12 |