A Bionic Study on the Anti-erosion Mechanism of Laudakia stoliczkana: Experimental and Numerical Aspects

The scales of body surface of Laudakia stoliczkana have the morphology of convex hulls, which are arranged in groove structure in macroscopic scale. Its body surface skin is mainly composed of the soft layer of keratin and the hard layer of the cuticle covering on the soft layer. The coupling effect of the scale morphology and skin's structure gives Laudakia stoliczkana the excellent ability to resist the sand erosion in desert environment. Inspired by the convex surface morphology and the composite structure of the soft and hard layers of the skin of Laudakia stoliczkana, the coupling bionic samples are fabricated and the erosion resistance performance is tested. The test results show that the coupling bionic samples have good erosion resistance performance and the samples with spherical convex hull exhibit the best erosion resistance performance. Moreover, based on the theory of stress wave propagation in solid the numerical simulations of particles impacting to the coupling bionic samples and bionic layered structure are done respectively and the anti-erosion mechanism of the bionic layered structure is analyzed. The simulation results are consistent with the experimental results, which show that the coupling bionic samples can effectively reduce the amplitude of the incident stress wave, and thus can prevent the failure of samples.