  We study acoustic streaming in liquids driven by a non-dissipative acoustic
body force created by light-induced temperature gradients. This thermoacoustic
streaming produces a velocity amplitude approximately 50 times higher than
boundary-driven Rayleigh streaming and 90 times higher than Rayleigh-Benard
convection at a temperature gradient of 10 K/mm in the channel. Further,
Rayleigh streaming is altered by the acoustic body force at a temperature
gradient of only 0.5 K/mm. The thermoacoustic streaming allows for modular flow
control and enhanced heat transfer at the microscale. Our study provides the
groundwork for studying microscale acoustic streaming coupled with temperature
fields.
