Optimizing the Strength of a Condenser Tube

Extruded multi-port aluminum tubes are widely used in current condenser applications. The cross-section of the tube has multiple rectangular ports (openings) that allow refrigerant to flow through. Since the tube is working with pressurized refrigerant, the burst pressure becomes an important specification of the tube. The objective of this study is to seek the optimized cross-section configuration for a given maximum burst capability. The first part of this study utilizes a linear elastic 2-D model which shows that octagonal shaped ports perform the best up to the yield point. The second part of the study utilizes a Finite Element Method (FEM) model with more detailed dimensions and material nonlinear elastic/plastic properties. A case study shows that an octagon-port tube could outperform the commonly used rectangular-port tube in burst resistance by 27 percent.