Losses in Linear Engines

Matthew Thom*, Terence Musho, Duncan Manor, Ramanjaneya Mehar Baba Bade and Jayaram Subramnian, Benjamin M. Statler College of Engineering and Mineral Resources, West Virginia University, Morgantown, WV 26506

Field (Broad Category): Engineering (Physical Sciences & Engineering) 

Student’s Major: Mechanical/Aerospace Engineering 

This study focuses on experimentally quantifying the energy loss per cycle for flexure springs that are currently being used in the design of a 1kW natural gas, combined heat and power (CHP) generator for domestic households. The unit currently being design at WVU is based on the working principle of a resonant linear engine that minimizes the losses that are typically associated with a traditional crack driven engine. A critical component in the linear engine design, and the focus of this study, are the flexure springs. Experimental testing has been performed to test the flexure springs at several different load profiles and frequencies using a hydraulic load frame. The force and displacement data was analyzed using MATLAB and the loss per cycle was quantized. Results indicated an increase in the energy loss per cycle with increasing frequency. These losses were reasoned to be due to heat generation and windage losses. 

Funding: ARPA-E 

Program/mechanism supporting research/creative efforts: WVU's Research Apprenticeship Program (RAP) & accompanying HONR 297-level course