Thermal energy storage device

Abstract

A thermal energy storage (“TES”) device including a vessel housing a continuous volume of a TES media, an input portion, an output portion, and a plurality of thermal energy transport members connected to the input portion and / or the output portion. The input portion receives thermal energy from a thermal energy source. The received thermal energy is transported by one or more of the thermal energy transport members to the output portion and / or the TES media for storage. One or more of the thermal energy transport members connected to the output portion transport stored thermal energy from the TES media to the output portion. The output portion is coupled to an external device, such as a Stirling engine, and configured to transfer thermal energy the external device. Optionally, selected ones of the thermal energy transport members connected to both the input and output portions may be insulated from the TES media.

Description

CROSS REFERENCE TO RELATED APPLICATION(S)[0001]The present application claims the benefit of U.S. Provisional Patent Application No. 61 / 079,787, filed Jul. 10, 2008, which is incorporated herein by reference in its entirety.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0002]The invention described herein was made under federally sponsored research and development with Department of the Navy contract no. N00014-07-M-0409 and may be manufactured and used by or for the United States Government for governmental purposes without the payment of any royalties thereon.BACKGROUND OF THE INVENTION[0003]1. Field Of The Invention[0004]The present invention is directed generally to thermal energy storage devices.[0005]2. Description of the Related Art[0006]The Stirling engine was first described in an 1816 patent issued to a Scottish clergyman named Robert Stirling. Many variants of the Stirling cycle were implemented over the next century and applied to applications such as pu...

AI Technical Summary

Problems solved by technology

Philips, its licensees and others developed many versions of Stirling engines and coolers aimed at a wide range of applications, but outside of a few cryocooler applications, no significant commercialization has occurred.

The primary reasons are the inherent life and reliability limitations imposed by the sliding seal in all kinematic Stirling machines (where piston and displacer motions are constrained by conventional crankshafts and related mechanisms), and the high cost that results from no engines having crossed the threshold from demonstration machines to high level production of an engine with comprehensive design for manufacture and assembly (“DFMA”).

Single acting alpha engines can only be implemented as kinematic machines since the resonant dynamic forces acting on free pistons cannot achieve a phase relationship that enables positive work output.

They are complicated and expensive to build, and require a lubricated crankcase, piston and rod seals, and mechanical bearings that restrict performance and limit life.

Power output is difficult to vary in a kinematic design, generally being accomplished by a complex system that pumps the helium or hydrogen working fluid back and forth between the engine and a storage reservoir to change the average working pressure in the engine.

However, some sources of thermal energy are not continuous.

Further, some thermal energy sources may supply more energy than is required to operate the Stirling engine.

Images