| Thermal management and energy input are required to maintain working fluids, i.e., liquefied natural gas, liquid nitrogen, and multi-phase fluids within their optimal working conditions. Increasing a pipes' thermal resistance, e.g., utilizing vacuum insulation, is one method of minimizing energy input. A dual-wall concentric pipe employing a vacuum in the annulus, along with low emissivity surface coatings, is an achievable and economically viable solution. In this study, an experimental setup was designed and utilized to measure the air leakage mass flow rate for single-wall unloaded and mechanically loaded dual-wall fiber reinforced polymeric composite specimens. The mass flow rates were used to develop intrinsic permeability coefficients to quantify leakage, and to determine the maximum serviceable pipe length for a mechanical vacuum pump. In addition, thermal resistance equations were developed to quantify the theoretical heat loss, and an economic study was performed to ascertain the viability for three applications. |
