Multi-scale Analysis Of Mechanical And Thermal Property Of Lightweight Natural Luffa Sponge Material

Natural selection,survival of the fittest.Life on Earth evolved over 3.5 billion years,resulting in more than 10 million species of life in the world today.In order to adapt complex living environment,such as high altitude,ocean,desert,ice field,etc.These creatures in nature often need to create better strength,stiffness,heat resistance,thermal insulation performance and other excellent characteristics under the condition of limited weight or volume.The basis of achieving these excellent characteristics is a variety of biological materials with different forms in the organism.As a kind of biological material with high porosity and hierarchical structure,luffa sponge is commonly used in People’s Daily life.Its geometry presents a unique spatial network with extremely low specific density,which can withstand quite high load.In this thesis,multi-scale thermal and mechanical analysis was carried out to explore the excellent characteristics of the unique geometric structure of the luffa material.The content of this thesis mainly includes:(1)The measurement of the basic properties of natural luffa sponge material,such as density,specific density,porosity,elastic modulus,compressive strength,thermal conductivity,etc.(2)The natural luffa sponge was scanned by a micro-CT scanner,and the 3D geometric model of it was established by image reconstruction technology.(3)The thermal and mechanical properties of natural loofah were evaluated by multi-scale thermal and mechanical analysis,which using the method of numerical simulation and experiment.(4)According to the unique geometrical characteristics of the luffa sponge structure,it was combined with the common heat insulation and energy absorption structure to carry out related bionic design,furthermore,the thermal and mechanical properties of these designed bionic structures were studied.In this thesis,the multi-scale thermal and mechanical analysis of luffa sponge material was carried out for the first time,which using the method of experiment and numerical simulation.This study provides a new research methods and ideas for bionic design of luffa sponge and other biomaterials.