Fuzzy estimation for transient distribution of internal thermal excitation in composite overwrapped pressure vessel

Abstract

• Set up a decentralized fuzzy inference for estimation of internal thermal excitation. • The inversion method possesses a good anti-ill-posedness character. • The transient temperature of gas cylinder is reconstructed by infrared thermography. • The infrared thermography of gas cylinder is collected at the actual inspection site. The representative composite overwrapped pressure vessel of vehicle-mounted composite compressed natural gas cylinder is taken as the research object. Based on the principle of double decentralized fuzzy inference with a temporal-spatial decoupling characteristic, an inversion scheme is established by which the infrared thermography of cylinder is employed to estimate the transient distribution of internal thermal excitation. In this scheme, the error vector of time series of the finite temperature measurement points on the surface of cylinder is processed by fuzzy inference, and then the transient distribution of internal thermal excitation is estimated. The influence of the number of measurement points and measurement errors on the inversion results is studied through numerical simulation. Furthermore, combined with the on-site gas cylinder inspection process, the internal thermal excitation of cylinder is estimated using the infrared thermography of cylinder under the steam flushing process obtained from the inspection site. According to the inversion results, the transient temperature field of cylinder is reconstructed, and the reliability of reconstruction results is also verified. The results show that under the experimental conditions in this paper, the maximum deviation of the surface temperature reconstruction results of cylinder is about 1.0 °C.