Experimental evaluation of the efficiency of a pneumatic strain energy accumulator

There is heightened interest in research to develop materials and devices that achieve greater energy storage capacity, power density and increased energy efficiency. This work analyses the performance of a novel energy storage device, the pneumatic strain energy accumulator (pSEA), which is designed to exploit the advantageous aspects of the non-linear behaviour of elastomeric materials. An analytical method for simultaneously characterising the pneumatic energy and strain energy stored in a strain energy accumulator (SEA), and more generally for pneumatic and strain energy systems, has been employed. Component efficiency along with the expansion and contraction pressures of the pSEA are determined experimentally so that a system level efficiency calculation can be performed. Incorporating uncertainty analysis, the efficiencies of the SEA are measured to be consistently over 93% in over 800 cycles of testing. The steady-state expansion and contraction pressures of the accumulator have steady-state values with errors of less than 3 hundredths of a kilopascal from their means. © 2017 Informa UK Limited, trading as Taylor & Francis Group.