Shape Memory Based Self-Powered Fluid Pump

In the range of 25°C -80°C (ultra-low grade heat), a large quantity of waste heat from various processes is available unused.Special alloys made of nickel and titanium, so-called Shape Memory Alloys (SMA), could be an alternative technology to Organic Rankine Cycles to make this energy usable in the low power range.The "THEAsmart 2" research project is therefore investigating the service life and energy lifecycle of this material to test the benefits of shape memory alloys in energy recovery and the efficiency levels that can be achieved.To this end, a demonstration prototype is being built that converts thermal energy into rotary motion.The next step is to link the demonstration prototype with a conventional fluid pump to create an SMA fluid pump that is driven by the thermal energy of the fluid to be pumped.The advantage of such a pump would be that it would be energy-independent, i.e. it would be operated solely by the thermal energy of the fluid without an electrical connection.Furthermore, such a pump could contribute to energy savings if it is used in cooling circuits in which the thermal energy of the fluid is the waste product from another process.In this case, it replaces an electric pump and utilizes the "waste product" heat.The aim of the project is to investigate how and whether coil springs made of shape memory alloy are suitable for energy recovery.This is considered via the energy lifecycle: if more energy is required to manufacture a spring than this spring can convert kinetic energy from thermal energy in its lifecycle, then its use for energy recovery does not make sense in principle.As a secondary result of this research, statements about the efficiency of shape memory alloy coil springs and statements about their service life are expected.