Thermal-Acoustic Wave Generation and Propagation Using Suspended Carbon Nanotube Thin Film in Fluidic Environments

A simplified analytical pressure solution for thermal-acoustic wave response generated by using suspended multiwall carbon nanotube (MWCNT) thin film in different fluidic environments is developed. The solution consists of two independent portions: the near-field solution and the far-field solution. The electricity power input is a key element to control the thermal-acoustic wave pressure level. The dependence of the solution on axial distance from the source origin is investigated for different fluidic environments. Comparison between analytical solutions and published experimental results is presented, and excellent agreement is reported. A number of numerical examples for different parameters are studied for various liquids and gases including air, argon, water, and ethanol. Accurate analytical approximations for the thermal-acoustic wave response, and amplitude functions for different temperatures in fluids of varying densities are proposed here. The relation of Rayleigh distance and critical frequency has been determined in order to enhance and optimize the thermal-acoustic effect and wave behavior in fluids. These two parameters can be modified by suitable choices of the size of thin film, the properties of surrounding media, etc. The thermal-acoustic generation properties including the electric power input, frequency, and the suspended MWCNT thin film size significantly affect the acoustic pressure performance. It is concluded here that this extended analytical work not only agrees better with experiment but also offers more convincing analytical prediction for the generation and propagation of thermal-acoustic wave in different fluids.