A method for cooling a circuit comprises generating movement of fluid along a path through a closed-loop system. The method further comprises inducing turbulence in the fluid by movement of at least a portion of a turbulence-inducing device arranged in the path, and dissipating thermal energy from the circuit by the fluid. A system comprises a circuit, and a closed-loop cooling system comprising fluid for cooling the circuit and at least one active turbulence-inducing device. In one embodiment, the turbulence-inducing device is a microelectromechanical system (MEMS) device. In one embodiment, the MEMS device is solely responsible for bulk fluid movement through the closed-loop cooling system.