• Journal of the Korean Society for Aviation and Aeronautics
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• v.14 no.1
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• pp.2-8
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• 2006

Numerical analysis of the flow field in the reactive medium of End-Burring combustor is studied in order to investigate the combustion characteristics of hybrid combustion. The main part of this study is focused on the port diameter effects of oxidizer injector on the temperature distribution within the reactive field. It is found that the case having the largest port diameter(25 mm) delivers the optimum conditions for the design of End-Burring combustor where the predicted temperature field showed the most acceptable distribution.

• Transactions of Materials Processing
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• v.26 no.5
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• pp.271-276
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• 2017

A tee is the most common pipefitting used to combine or divide fluid flow. Tees can connect pipes of different diameters or change the direction of a pipe run. To manufacture tee type of stainless steel pipe, combinations of punch piercing and burr forming have been widely used in the industry. However, such method is considerably time consuming with regard to performing empirical work necessary to attain process conditions to prevent upper end tearing of the tee product and meet target tee height. Numerous experiments have shown that the piercing profile is the main cause of defects mentioned above. Furthermore, the mold design is formed through trial and error according to pipe diameters and changes in requirements. Thus, the objective of this study was to perform piercing and burring process analysis via finite element analysis using DYNAFORM to resolve problems mentioned above. An optimization design method was used to determine the piercing punch profile. Three radii of the piercing punch (i.e., large, small, and joined radii) were selected as design variables to minimize thinning of a tee pipe. Based on results of correlation and multiple regression analyses, we developed a predictive approximation model to satisfy requirements for both thickness reduction and target height. The new piercing punch profile was then applied to actual tee forming using the developed prediction equation. Model results were found to be in good agreement with experimental results.