Study On The Basic Properties Of Heating Elements Containing Carbon Nanotubes Composites

When an aircraft flies through the clouds at subsonic speed,its surface may be hit by super-cooled water droplets and hence ice layer may be formed.Aircraft icing is a huge threat to the aircraft's performance,aerodynamics and security,it can cause even a crash.The anti-icing and de-icing problems are of great importance in aircraft design.In recent years,the electro-thermal de-icing technology,has drawn more and more attentions due to its advantages such as low energy consumption,good anti-icing/de-icing effect and control tractability.Carbon nanotubes(CNTs)have excellent mechanical properties,electrical conductivity and heat transfer performance.The stiffness,melting point and conductivity of CNTs are much higher than traditional metal materials.The present paper studies the possibility of using thin polymer film which contains CNTs as a heating element,the main contents of the paper are as follows:(1)The CNTs/epoxy resin composite and the nonwoven CNTs/epoxy resin composite were both manufactured.The electrical and mechanical properties of the two composites were tested and analyzed.The nonwoven CNTs/epoxy resin composite was chosen since it had higher efficiency and safety performance as the heating element.(2)A new electro-thermal anti-icing scheme was proposed and manufactured,which integrates the skin,the heating elements,the electric insulating layer and the thermal insulation layer into a whole mold.The experimental system to test the new anti-icing scheme was set up.The test data showed that the temperature of the flat plate-shaped heating device rose to a high temperature at a rather fast speed in laboratory environment,so it is possible reach de-icing requirement quickly.(3)The experimental results were verified by numerical simulation and theoretical analysis.Firstly,the modified rule of mixture and Halpin-Tsai model were used to predict the mechanical property of nonwoven CNTs/epoxy resin composite,the theoretical prediction has good agreement with the experimental results.And based on the mechanics of composite materials,the mechanical property of the sample was analyzed too.Secondly,the heating process of the skin sample under room temperature was calculated.Also,the heating process was simulated by FLUENT using instant heat transfer model,the results agreed well with experiment results.The nonwoven CNTs /epoxy resin composite have the advantages of simple production process,good electrical conductivity,heat transfer performance,and mechanical properties.It can be used as new electro-heating material,and has beneficial effect for the electro-thermal anti-icing/de-icing technology.