Transient Thermofluid simulation of a Hybrid Thermoacoustic system

Abstract A transient simulation of a hybrid thermoacoustic system is used to study temporal evolution of flow structures as well as the velocity and temperature variations within the channels of the stack. The numerical results and experimental data showed good agreement with a difference of 4.29 % and 4.2 % respectively between the amplitudes of the pressure and axial velocity over one full cycle and generated identical flow structures. The simulation results further show the presence of a residual vortex layer inside the channel which can accelerate the velocity near the edges and decelerate the velocity near the center of the channel. Velocity peaks and temperature peaks or dips in the profile can be seen near the edges of the stack plates and are more prominent at resonance frequencies. At the same frequency, increasing the mean pressure shifts the peaks closer to the wall. The maximum pressure amplitude and net heat flux also increases with the mean pressure for different working fluids.