Design, Fabrication, and Testing of 10 MJ Composite Flywheel Energy Storage Rotors

Herbst, J.D.; Manifold, S.M.; Murphy, Brian T.; Price, J.H.; Thompson, Richard C.; Walls, W.A.; Alexander, A.; Twigg, K.

doi:10.4271/981282

Cited by 11 publications

(9 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…21,22,24,29 By using the interference fitting in the multi-ring composite rotor, the pre-stress developed by the interference can reduce the net stresses in the rotating rotor and yield a higher rotary speed and higher energy storage capacity. [43][44][45][46][47][48][49] Besides, the variation of the fiber orientation in each ring could reduce the stresses and eventually yield a higher energy storage capacity. 29,50 A structural analysis has been performed considering not only the interference between rings but also the ring-by-ring variation of material properties due to the different fiber orientation.…”

Section: Introductionmentioning

confidence: 99%

Hollow interference fitted multi-ring composite rotor of the superconducting attitude control and energy storage flywheel

Tang

Zhang

et al. 2013

Journal of Reinforced Plastics and Composites

View full text Add to dashboard Cite

The superconducting attitude control and energy storage flywheel is a kind of energy storage flywheel. With respect to this kind of flywheel, a rotor consisting of a hollow hub and three composite cylindrical rings in interference fitted state is presented to achieve high specific energy density. The hollow hub made of high strength steel 18Ni350 is used to change the distribution of centrifugal stress, reduce the maximum radial stress and to ensure the working gap of radial magnetic bearings and motor/generator is constant when the rotor rotates at a high rotary speed. Interference has been introduced between rings or ring and hub to avoid their delamination and eventually increase the maximum speed of the rotor. In order to find out the quantitative relationship among interference, tension force, radial pre-stress and so on, we analyzed the stress distribution of the rotor subjected to centrifugal loads, the initial stresses and displacements of the multi-rings rotor in interference fitted state by mathematical methods and finite element methods. Effects of these factors, such as interference between rings, thickness ratio of rings, different materials of rings and so on, are studied in detail to make clear how they affect the stress distribution of the interference fitted multi-ring composite rotor. The results of this study will give a useful hint for the design, test and manufacture of the composite rotor for the superconducting attitude control and energy storage flywheel.

show abstract

Section: Introductionmentioning

confidence: 99%

Hollow interference fitted multi-ring composite rotor of the superconducting attitude control and energy storage flywheel

Tang

Zhang

et al. 2013

Journal of Reinforced Plastics and Composites

View full text Add to dashboard Cite

show abstract

“…A KINETIC ENERGY storage system with high energy density and long life has been under development for many applications [1][2][3][4][5][6][7][8][9][10][11][12]. Composite materials have been widely used because they can be very effective at both increasing the energy and decreasing the total mass.…”

Section: Introductionmentioning

confidence: 99%

Design and Manufacture of a Composite Flywheel Press-Fit Multi-Rim Rotor

Han

2008

Journal of Reinforced Plastics and Composites

View full text Add to dashboard Cite

The pre-compression that develops in a press-fit multi-rim rotor suppresses tensile stresses caused by the curing process and high speed rotational centrifugal forces, increasing the overall performance of the flywheel rotor. In this study, the interferences and the rim thickness of up to five rims of graphite/Ep and glass/Ep are analyzed to maximize the specific energy density (SED) of a multi-rim composite flywheel rotor. Three states are considered: (a) cured rims with residual stress prior to press-fitting; (b) a stationary press-fitted rotor; (c) a rotor at maximum rotational speed. Two methods of press-fitting rims are presented. One method has each rim machined with tapered inner and outer rim surfaces. The other method uses a guiding rim to expand the outer rim and guide the inner rim into the expanded outer rim. An optimized multi-rim rotor, composed of one glass/Ep rim and one graphite/Ep rim, is scaled to have energy storage capability of 5 kWh, and is successfully manufactured by machining tapered rims and hydraulic pressing.

show abstract

“…To generate favorable stresses in the rotor, interferences can be introduced between rims and hubs by press-fit or shrink-fit [3,16,17]. Such interferences cause the initial compressive stresses which effectively offset the tensile stresses developing during rotor spinning.…”

Section: Introductionmentioning

confidence: 99%

Design and Spin Test of a Hybrid Composite Flywheel Rotor with a Split Type Hub

Kim

Han³

et al. 2006

Journal of Composite Materials

View full text Add to dashboard Cite

A study is conducted on lowering the radial tensile stresses and increasing the performance of the fiber wound composite flywheel rotor by applying pressure on the inner surface of the rotor using a split type hub that spreads in the radial direction due to the centrifugal force. A conventional solid or ring type hub in most cases produces tensile stresses within the rotor, possibly causing delamination and eventually lowering the maximum speed of the rotor. The relationship between the stresses of the rotor and the thickness of the hub is derived and applied to the single and hybrid rotors. A hybrid composite rotor of 180 mm inner diameter and 340 mm outer diameter is designed and fabricated, which reaches only the strength ratio of 0.58 at the maximum rotating speed of 40,000 rpm. A spin test was conducted to show the improved performance of the rotor with the split type hub by measuring the mechanical strains from the rotor. The radial and circumferential strains at four different locations are measured up to 30,000 rpm using a wireless telemetry system, and they are in good agreement with the analytical calculations. The rotor has survived a spin test of up to 40,000 rpm, which corresponds to the usable energy of at least 500 W h with the safety factor of 1.7.

show abstract

Design, Fabrication, and Testing of 10 MJ Composite Flywheel Energy Storage Rotors

Cited by 11 publications

References 3 publications

Hollow interference fitted multi-ring composite rotor of the superconducting attitude control and energy storage flywheel

Hollow interference fitted multi-ring composite rotor of the superconducting attitude control and energy storage flywheel

Design and Manufacture of a Composite Flywheel Press-Fit Multi-Rim Rotor

Design and Spin Test of a Hybrid Composite Flywheel Rotor with a Split Type Hub

Contact Info

Product

Resources

About