STUDY ON CHARACTERISTICS OF THERMOACOUSTIC STREAMING BY MICROGRAVITY EXPERIMENT AND NUMERICAL SIMULATION

摘要

Thermcracoustic streaming is a new thermal convection. It was discovered in our past work in which a droplet was burnt in standing sound waves in microgravity experiments. When the droplet is placed between a node and an anti-node, the flame is blown in one direction and is placed at a node and an anti-node, the flame is not blown. In the previous report, to investigate the flow field of the streaming, the authors made numerical simulations by direct numerical simulation (DNS). The DNS, however, is too inefficient to simulate the streaming, because it takes a lot of time steps to solve. We developed a time-averaged model named as "Acoustic Radiation Force model (ARF model)". The authors, however, have not investigated whether the simulations give flow field consistent with the experimentally generated streaming. To certify the simulation models, the authors visualized the flow filed of the experiments by schlieren method. Microgravity is used in the experiments to remove the effects of buoyancy. As a result, the simulation models are validated to give flow field consistent with the streaming in reality.