Numerical simulation on onset characteristics of traveling-wave thermoacoustic engines based on a time-domain network model
Sun, Da Ming
Qiu, Li Min
Huang, Z. Y.
Date of Issue2015
Energy Research Institute
Onset characteristics of thermoacoustic engines are of great importance for understanding the internal working mechanisms of thermoacoustic conversion. A one-dimensional time-domain network model for predicting the onset characteristics of traveling-wave thermoacoustic engines with helium as working gas is built. The acoustic resistance, inertance, compliance, and thermal-relaxation effects of all the acoustic components are included. The viscous and heat transfer terms in the time-domain governing equations of the acoustic tubes and the heat exchangers are deduced from the frequency-domain linear thermoacoustic theory. Combining the time-domain governing equations of the regenerator, numerical simulations of the whole onset process are then conducted in a wide operating condition range. The complete dynamic pressure wave evolution processes are simulated successfully. It is shown that a steady standing-wave acoustic field forms in almost all parts of the traveling-wave thermoacoustic engine except for the regenerator area. Onset temperature, operating frequency, and quality factor are calculated with a relatively high accuracy. The thermal relaxation effects in the regenerator are found to have a remarkable impact on the onset characteristics, especially at high mean pressures. It is also shown that the experimental damping temperature is closer to the calculated onset temperature than the experimental onset temperature. Furthermore, the reasonable distributions of the pressure and volume flow rate and the phase relationship between them in the whole system are obtained and analyzed.
DRNTU::Science::Physics::Heat and thermodynamics
International journal of thermal sciences
© 2015 Elsevier Masson SAS. This is the author created version of a work that has been peer reviewed and accepted for publication by International Journal of Thermal Sciences, Elsevier Masson SAS. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [http://dx.doi.org/10.1016/j.ijthermalsci.2015.02.010].