Weight Minimization of Natural Gas Distribution Riser Systems

This study investigates the optimal piping layout in the installation of residential natural gas riser piping systems subjected to daily temperature fluctuations. Specifically, it is desired to evaluate the optimal safe configuration for minimum weight requirements in the absence of flexible expansion joints between the riser pipe and the branches. Structural optimization is carried out using fully parametric finite element models employing the singular value decomposition algorithm. Thermally induced stresses are examined to identify the optimal layout. The results indicate that the optimal piping layout satisfies strength requirements and achieves significant weight reduction and hence cost saving compared with existing, rule-based configurations.