Lightweight containment for high-energy rotating machines

Abstract

Abstract--The University of Texas Center for Electromechanics (UT-CEM), as a member of the Defense Advanced Research Projects Agency (DARPA) Flywheel Safety and Containment program, has developed a lightweight containment system for high-speed, composite rotors. The containment device, consisting of a rotatable, composite structure has been demonstrated to contain the high-energy release from a rotor burst event and is applicable to composite rotors for pulsed power applications. UT-CEM recently conducted a burst spin test of a composite flywheel inside this composite containment device at Test Devices Incorporated (TDI) of Hudson MA. The most important aspect of this design is that the free-floating containment structure dissipates the major loads (radial, torque, and axial) encountered during the burst event, greatly reducing the loads that pass through the stator structure to its attachments. The design results in significant system-level weight savings for the entire rotating machine when compared to a system with an all-metallic containment. Of equal interest to the containment design, the experimental design and instrumentation was very challenging and resulted in significant lessons learned. This paper describes the containment system design, rotor burst test setup, instrumentation for measuring loads induced by the burst event, and a detailed explanation of the successful containment test results and conclusions.

A review of critical issues in the design of lightweight flywheel rotors with composite materials

“…To absorb this rotational energy, a free-rotating liner can be placed inside the containment, thus the torque transmission can be slowed down, reducing the torque loads on the containment and thus the weight. The third approach is to use energy absorbing liner, which is typically built with "soft" K A review of critical issues in the design of lightweight flywheel rotors with composite materials 215 and ductile materials or structures [81,82]. The energy of the debris can be quickly absorbed by a shape change of the liners, thus reducing the peak forces.…”

Design and Experimental Evaluation of a Low-Cost Test Rig for Flywheel Energy Storage Burst Containment Investigation

“…More recent studies dealing with turbine disc failure were published by the Zhejiang University in China [27]. Some notable FESS-specific investigations regarding containment structures were conducted by the Center for Electromechanics at University of Austin, Texas and are described for example in [20,28,29].…”

Preliminary Design and Analysis of an Energy Storage Flywheel

“…There has been some experimental evidence showing this behavior. Particularly, the Demo IC failure conducted at the Oak Ridge National Laboratory[149], the intentional burst failure of the flywheel rotor at Munich[141]and the flywheel safety and containment program at the Defense advanced research projects agency (DARPA) [150] are good examples. Design approach to reduce flywheel risk With the significant amount of evidence showing the hazards involved with a high speed flywheel burst mode failure; it is not acceptable to downplay the issue of safety and containment.…”