Durable High Efficiency Heat Engine based on Multi-Component Shape Memory Alloys (DHENG – SMA)

The emergence and proliferation of small wireless sensor networks, such as structural health monitoring sensors, has increased the demand for improved energy harvesting solutions that alleviate the need for batteries or wired power. Consequently, the interest in shape memory alloy (SMA) heat engines to harvest low-gradient heat has grown up with the development of wireless sensors. In this research, we will develop a novel heat engine, based on SMAs, to capture waste thermal energy with low temperature gradients to power small wireless sensor networks. Our approach contains three key innovation modules: 1) design of novel SMA materials with remarkable functional and structural fatigue and low thermal hysteresis, 2) design of a novel heat engine architecture with large power density and high energy conversion efficiency, and 3) design of a novel self-start management circuit (PMC) for continuous harvesting and storing electrical power. Our project goals are to achieve high power density: >50 W/kg of SMA in the Phase I, and >65 W/kg of SMA in the Phase II. We envision that the technology can be employed not only by defense manufacturers and suppliers but also by other segments such as automobiles, energy, civil infrastructures, biomedical equipment, electronics, etc.