双壁纳米碳管的谐振与能量耗散特点的研究

The Analysis about Double-walled Carbon Nanotubes Resonant with the Phenomenon of Energy Dissipation

运用分子动力学模拟方法模拟气体环境下双壁碳纳米管振荡器的谐振现象和能量耗散。在真空条件下建立双壁纳米碳管谐振子模型,验证双壁碳纳米管振荡器谐振现象,得到内碳管振动位移曲线及在此过程中内碳管所受回复力的变化情况,并讨论温度对同一碳管管型的谐振频率的影响。通过对谐振过程中存在的能量损耗的分析,提出从能量损耗角度来讨论摩擦的方法,得到碳管谐振过程中摩擦力的变化情况。结果表明:双壁碳纳米管的运动类似于弹簧振子的运动,其振幅的衰减快慢与温度有关,温度越高,衰减得越快;摩擦力会导致能量耗散,温度越高,内外碳管间的摩擦力也越大,能量耗散的也越多;双壁碳管中的内碳管在运动中所受的回复力与温度没有关系。

The double-walled carbon nanotube oscillator resonant phenomena and energy dissipation were simulated by use of molecular dynamics simulation.The double-walled carbon nanotube oscillator model in the vacuum was established,and the double-walled carbon nanotube oscillator resonance phenomenon was verified,the vibration displacement curve of carbon tubes versus time and the changes in restoring force of carbon tubes suffered in the process of oscillation process were obtained.The effect of temperatures on the resonance frequency of the same type of carbon tube was discussed.Based on the energy loss analysis in the process of resonant,the method to discuss the friction from the point of view of energy loss was put forward,the friction of carbon tube in the process of resonant was obtained.The simulation results show that the movement of double-walled carbon nanotube is similar to that of spring oscillator,and the amplitude attenuation speed is related with the temperature,higher temperature will result in greater amplitude attenuation speed.Friction causes the energy dissipation,the higher the system temperature,the greater the energy dissipation due to the friction.The restoring force of double-walled carbon nanotube sustains constant,which does not depended on the temperature.