Abstract
ABSTRACTShark skin surfaces show non-smoothness characteristics due to the presence of a riblet structure. In this study, biomimetic shark skin was prepared by using the polydimethylsiloxane (PDMS)-embedded elastomeric stamping (PEES) method. Scanning electron microscopy (SEM) was used to examine the surface microstructure and fine structure of shark skin and biomimetic shark skin. To analyse the hydrophobic mechanism of the shark skin surface microstructure, the effect of biomimetic shark skin surface microstructure on surface wettability was evaluated by recording water contact angle. Additionally, protein adhesion experiments and anti-algae adhesion performance testing experiments were used to investigate and evaluate the anti-biofouling properties of the surface microstructure of biomimetic shark skin. The recorded values of the water contact angle of differently microstructured surfaces revealed that specific microstructures have certain effects on surface wettability. The anti-biofouling properties of the biomimetic shark skin surface with microstructures were superior to a smooth surface using the same polymers as substrates. Moreover, the air layer fixed on the surface of the biomimetic shark skin was found to play a key role in their antibiont adhesion property. An experiment into drag reduction was also conducted. Based on the experimental results, the microstructured surface of the prepared biomimetic shark skin played a significant role in reducing drag. The maximum of drag reduction rate is 12.5%, which is higher than the corresponding maximum drag reduction rate of membrane material with a smooth surface.
Highlights
Bionics has been defined as biologically inspired design which has been adapted or derived from nature (Bhushan, 2009)
This observation indicates that the surface morphology of the dermal denticles on shark skin can be simulated by means of replication techniques
In this study, the microstructures of the shark skin surface were replicated on the surface of PDMS and PU sheets by the PEES method
Summary
Bionics has been defined as biologically inspired design which has been adapted or derived from nature (Bhushan, 2009). A fine example of bionic design is the biomimetic drag reduction that is achieved using a special microstructure surface which emulates the non-smooth surface of certain natural organisms. Such an example is the shark skin effect, which is defined as a mechanism of fluid drag reduction by a riblet. Sharks’ skin has been extensively studied for decades because of its drag-reduction and antifouling properties (Friedmann et al, 2010; Han and Zhang, 2008; Kesel and Liedert, 2007)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
