Structural Modeling and Optimization of Circular Tubes in A Mechanically Assembled Condenser

Recently mechanically assembled heat exchangers became attractive due to their cost advantage. The optimization of the tube structure was in demand because test results showed that the current tubes used in the mechanical heat exchanger may not be optimized. The objective of this study is to find sophisticated and effective structural modeling techniques so that optimization studies can be performed. Two methodologies were used in the study with a focus on the load distribution and the load sharing mechanisms between the tube and the surrounding fins. The first method is performed by analysis of the mechanics in a simple model. The close-form solutions provided explicit relationships between the load applied and the stresses generated. The second method used is a computer generated finite element analysis (FEA) model with more consideration to geometric details, material non-linearity, and boundary conditions. By understanding the load sharing and load distribution mechanisms, the tube thickness requirement can be precisely optimized. The models were applied to a currently produced mechanical condenser. It was found that the tube wall thickness could be reduced significantly.