This work details the effect of top membrane compliance on the performance of a MEMS based micro-heat engine and integrated thermal switch at operating speeds of 20, 40, and 100Hz and heat inputs of up to 60mJ per cycle. The engine consists of two flexible membranes encapsulating a volume of saturated working fluid. A thermal switch is used to intermittently reject heat from the engine to a constant temperature cooling sink. Mechanical work output is measured based on the engine's top membrane deflection and internal operating pressure. Three top membranes are considered; a 2micron thick silicon membrane, a 300nm thick silicon-nitride membrane, and a 3micron thick corrugated silicon membrane. The engine is shown to produce 1.0mW of mechanical power when operated at 100Hz.

Volume Subject Area:
Advanced Energy Systems
Topics:
Heat engines, Microelectromechanical systems, Switches, Membranes, Engines, Heat, Silicon, Cooling, Cycles, Deflection, Fluids, Pressure, Silicon nitride ceramics, Temperature
1.
A. Mehra, X. Zhang, A.A. Ayon, I.A., Waitz, M.A., Schmidt and C.M. Spadaccini, “A Six-Wafer Combustion System for a Silicon Micro Gas Turbine Engine,” J.MEMS, Vol.9, No. 4 (2000)
2.
H. T. Aichlmayr, D. B. Kittelson, and M. R. Zachariah. “Miniature free-piston homogeneous charge compression ignition engine-compressor concept—Part I: performance estimation and design considerations unique to small dimensions,” Chemical Engineering Science Vol.57 (2002)
3.
K. Fu, A. J. Knobloch, F.C. Marinez, D.C. Walther, C. Fernandez-Pello, A.P. Pisano, D. Liepmann, “Design and Fabrication of a Silicon-Based MEMS Rotary Engine,” Proc. ASME IMECE 2001, Paper No. MEMS-23925, New York (2001).
4.
T. S. Wiser. “Steady State Heat Transfer Characterization of a Liquid-Metal Thermal Switch,” MS Thesis, Washington State University, 2005.
5.
Weiss
L. W.
,
Cho
J. H.
,
McNeil
K. E.
,
Bahr
D. F.
,
Richards
C. D.
and
Richards
R. F.
. “
Characterization of a dynamic micro heat engine with integrated thermal switch
.”
Journal of Micromechanics and Microengineering
.
2006
,
16
S262–S269
S262–S269
6.
S.A. Whalen, D.F. Bahr, C.D. Richards, and R.F.Richards, “Characterization of a Liquid-Vapor Phase-Change Actuator,” Proc. of ASME IMECE, Florida, U.S.A., Nov. 5–11, 2005, Paper No. IMECE-82564
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