Location-Based Integration of Internal Lattice Structures in a Turbine Blade for Mass Reduction and Dynamic Characteristic Comparison

The robust design and the high aspect ratio of conventional turbine blades cause resonance at lower frequencies and have a short operational life. Expensive low-dense materials can enhance their dynamic characteristics. Owing to the lattice structures well-known high strength-to-weight ratio, they can be advantageous for the turbine blades. This paper compares several lattice designs based on the percent change of mass and natural frequencies when integrated inside a turbine blade. The proposed approach involves forming a cavity inside a solid turbine blade by removing a portion of its internal volume and correlating natural frequencies numerically and experimentally through additive manufacturing using PLA and aluminum alloy. The lattice structures are integrated at three distinct locations to maximize the natural frequencies and compared by making three configurations. Five different lattice structures were utilized in this study. The removal of volume from the solid blade enhanced the natural frequencies by 9.92% and 3.69% with a 35% weight reduction. The lattice structure integrated turbine blade showed 16.44% and 8.6% enhancement in the frequencies with only 2% of mass inclusion.