Heat storage device for an engine

Abstract

A heat recovery system for an engine is disclosed herein utilizing a heat storage unit configured to store waste exhaust heat for subsequent use on engine starts in various systems. In this way, improved system operation can be obtained by re-using such waste heat.

1 . A heat storage device for an engine, comprising:
 an inlet passage thermally coupling the heat storage device to an exhaust passage;   a stack of phase changing materials positioned radially about a central feed passage, the stack positioned within an interior of a double wall vessel; and   an outlet passage thermally coupling the heat storage device to another engine system.   
     
     
         2 . The device of  claim 1 , wherein the inlet passage is coupled to an end of the heat storage device at a centrally located position. 
     
     
         3 . The device of  claim 1 , wherein the outlet passage is coupled to another opposite end of the heat storage device, the outlet passage at a top periphery located position. 
     
     
         4 . The device of  claim 1 , further comprising a vacuum passage in fluidic communication with a vacuum space of the double wall vessel. 
     
     
         5 . The device of  claim 4 , wherein the double wall includes outer walls and inner walls, and wherein a vacuum jacket is positioned between the outer walls and the inner walls. 
     
     
         6 . The device of  claim 5 , wherein the inlet passage and the outlet passage include outer walls, inner walls, and a vacuum space between the outer walls and the inner walls, the vacuum space in fluidic communication with the vacuum jacket. 
     
     
         7 . A system for an engine, comprising:
 a heat exchanger in fluidic communication with an exhaust passage;   a heat storage device including a phase changing material;   a first pipe thermally coupling the heat exchanger to the heat storage device; and   a second pipe thermally coupling the heat storage device to another engine system.   
     
     
         8 . The system of  claim 7 , wherein the first and second heat pipes include a phase changing material. 
     
     
         9 . The system of  claim 7 , wherein the phase changing material of the heat storage device is positioned radially about a central feed passage. 
     
     
         10 . The system of  claim 7 , wherein the heat storage device includes more than one phase changing material, each phase changing material having a different phase transfer temperature. 
     
     
         11 . The system of  claim 7 , wherein the heat storage device is a double walled vessel including an inner vessel and an outer vessel separated by a vacuum jacket. 
     
     
         12 . The system of  claim 11 , further comprising a plurality of anti-radiation foils positioned within the vacuum jacket. 
     
     
         13 . The system of  claim 12 , further comprising a vacuum passage fluidically coupling the vacuum jacket to a vacuum pump. 
     
     
         14 . The system of  claim 7 , wherein the heat storage device is tilted 5 degrees from a horizontal, wherein the another system is separate from the heat exchanger and the heat storage device, wherein only the second heat pipe couples the another system to the heat storage device, wherein the another system includes a fluid conduit separate from the second heat pipe, wherein the fluid conduit is in thermal contact with the second heat pipe at a position coinciding with another heat exchanger, wherein the another heat exchanger is a location where heat transfer occurs between the second heat pipe and the fluid conduit, and wherein the another system is selected from the group consisting of a cabin heating system, a coolant system, and a transmission system. 
     
     
         15 . A heat transfer system for an engine, comprising:
 a heat exchanger coupled to an exhaust passage downstream from a catalytic converter;   a heat storage device, coupled to the heat exchanger via an inlet, including a cylindrical stack positioned between two retention plates; and   an outlet coupling the heat storage device to another engine system.   
     
     
         16 . The heat transfer system of  claim 15 , wherein the heat storage device is a double walled vessel including inner walls, outer walls, and a vacuum jacket between the inner and outer walls. 
     
     
         17 . The heat transfer system of  claim 16 , wherein the stack circumferentially surrounds a central feed passage that supplies a heat transfer fluid to the heat storage device. 
     
     
         18 . The heat transfer system of  claim 17 , further comprising one or more springs coupled to one retention plate and the inner walls of the double walled vessel. 
     
     
         19 . The heat transfer system of  claim 16 , wherein the inlet and the outlet include double walls with a vacuum space between inner and outer walls, and wherein the vacuum space is continuous with the vacuum jacket.