This work presents an innovative honeycomb cell geometry design with enhanced in-plane energy abs... more This work presents an innovative honeycomb cell geometry design with enhanced in-plane energy absorption under quasi-static lateral loads. Numerical and experimental compression tests results under axial and lateral loads are analyzed. The proposed cell geometry was designed to overcome the limitations posed by standard hexagonal honeycombs, which show relatively low stiffness and energy absorption under loads that have a significant lateral component. To achieve this, the new cell geometry was designed with internal diagonal walls to support the external walls, increasing its stiffness and impact energy absorption in comparison with the hexagonal cell. 3D-printed unit-cell specimens made from ABS thermoplastic material were subjected to experimental quasi-static compression tests, in both lateral and axial directions. Energy absorption was compared to that of the standard hexagonal cell, with the same mass and height. Finite element models were developed and validated using experim...
A crucial step in the mathematical modeling of a gas turbine engine is the characteristic map dev... more A crucial step in the mathematical modeling of a gas turbine engine is the characteristic map development of its main components, the compressor and the turbine. Maps can be obtained from manufacturers, although they are generally not available to the user. Furthermore, the construction of these maps through experiments is expensive. Analytical models prove to be economically more advantageous. Compared to other methods, they require little experimental data to be validated. These models are based on physical principles, so the results are more accurate compared to those obtained through numerical simulations or the use of neural networks. This approach allows more flexibility to make changes to the performance characteristics of engine components. These changes may be achieved by modifying certain geometric measurements, this quality could be used in diagnostic and/or engine control systems. In this work the characteristic map of the SR-30 turbojet engine components is analytically...
A major obstacle to obtaining cost-effective experimental data on the fatigue life of sandwich pa... more A major obstacle to obtaining cost-effective experimental data on the fatigue life of sandwich panels is the prohibitive amount of time and cost required to carry out millions of cycles. On the other hand, vibration techniques applied to sandwich geometries fail to match the stress patterns that are obtained from standard flexural fatigue tests. To overcome such limitations, a vibration-based fatigue technique is proposed, which entails the use of sandwich specimens whose geometries are optimized to reproduce the stress distribution observed during three point bend loading while vibrating at the first resonant frequency. The proposed vibration technique was experimentally validated. The results, compared with the average number of cycles to failure at different stress ratios obtained via the Three-Point Bending test, showed high levels of accuracy. The proposed method is robust and time effective and indicates the possibility of attaining fatigue lifetime prediction of a wide class ...
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Papers by David Serrano