Exhaust heat recovery device

Patent metadata

Field	Value
Publication number	US-9458792-B2
Application number	US-201314420296-A
Country	US
Kind code	B2
Filing date	Aug 1, 2013
Priority date	Aug 7, 2012
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

An exhaust heat recovery device includes: a heating part for exchanging heat between a heating fluid and a working fluid; and a condensing part for exchanging heat between the working fluid evaporated by the heating part and a heated fluid to thereby condense the working fluid. The heating part has a tube in which the working fluid flows and whose upper end portion in a vertical direction is opened and whose lower end portion in the vertical direction is closed. The heating part has a storing part provided on an upper side in the vertical direction thereof, the storing part having a tube joint part to which the upper end portion in the vertical direction of the tube is joined and storing the working fluid condensed by the condensing part. The storing part has a condensed liquid holding part for holding the condensed working fluid.

First claim

The invention claimed is:

1. An exhaust heat recovery device comprising:
a heating part that exchanges heat between heating fluid and working fluid, which is enclosed in the heating part and is capable of being evaporated and condensed, so as to evaporate the working fluid,
the heating part includes a tube through which the working fluid flows;
an upper end portion of the tube in a vertical direction opens; and
a lower end portion of the tube in the vertical direction is closed;

a condensing part that exchanges heat between the working fluid evaporated by the heating part and heated fluid so as to condense the working fluid; and
a storing part located outside of the tube is provided on an upper side of the heating part in the vertical direction and stores the working fluid condensed by the condensing part, the storing part includes a tube joint part that is joined to the upper end portion of the tube.

2. An exhaust heat recovery device comprising:
a heating part that exchanges heat between heating fluid and working fluid, which is enclosed in the heating part and is capable of being evaporated and condensed, so as to evaporate the working fluid,
the heating part includes a tube through which the working fluid flows;
an upper end portion of the tube in a vertical direction opens; and
a lower end portion of the tube in the vertical direction is closed;

a condensing part that exchanges heat between the working fluid evaporated by the heating part and heated fluid so as to condense the working fluid;
a storing part located outside of the tube is provided on an upper side of the heating part in the vertical direction and stores the working fluid condensed by the condensing part, the storing part includes:
a tube joint part that is joined to the upper end portion of the tube;

a condensed working fluid passage that introduces the working fluid condensed by the condensing part to the storing part; and
a valve that opens or closes the condensed working fluid passage and is configured to close the condensed working fluid passage when temperature of the working fluid flowing through the condensed working fluid passage reaches a predetermined standard temperature or higher.

3. The exhaust heat recovery device according to claim 2 , wherein the upper end portion of the tube is arranged on a vertically upper side of a lower end surface of the tube joint part in the vertical direction.

4. The exhaust heat recovery device according to claim 2 , further comprising:
a bypass passage through which the working fluid condensed by the condensing part flows to bypass the valve into the storing part.

5. The exhaust heat recovery device according to claim 2 , wherein:
the tube includes a fin that accelerates a heat transfer between the heating fluid and the working fluid; and
the fin is formed by plastically working an outside surface of the tube into a spiral shape.

6. The exhaust heat recovery device according to claim 2 , wherein:
the tube includes a fin that accelerates a heat transfer between the heating fluid and the working fluid; and
the fin is formed by knurling an outside surface of the tube.

7. The exhaust heat recovery device according to claim 2 , wherein:
the tube includes a groove part that is formed on an inside surface of the tube; and
the groove part absorbs the working fluid stored in the storing part by capillary force to supply the working fluid to the tube.

8. The exhaust heat recovery device according to claim 2 , further comprising a heat conduction limiting member between the heating part and the storing part, wherein the heat conduction limiting member limits a heat conduction from the heating fluid for the heating part to the working fluid in the storing part.

9. The exhaust heat recovery device according to claim 2 , wherein:
the tube is formed in a shape of a hollow cylinder having a closed end, and includes a side surface portion, a bottom portion, and a corner portion between the side surface portion and the bottom portion; and
the corner portion is formed in a shape of a circular arc.

10. The exhaust heat recovery device according to claim 2 , wherein M 1 , which is a lower limit value of a volume of the enclosed working fluid, and M 2 , which is an upper limit value of the volume of the enclosed working fluid are set to satisfy a relationship expressed by the following first mathematical formula and second mathematical formula:
M 1 =V w +0.4 V g ;  (first mathematical formula)

and
M 2 =V w /2+ V c +150exp(−11×α g F g /α w F w ),  (second mathematical formula)

where:
F g is a total sum of a heat transfer area between the heating fluid and the working fluid in the heating part;
V g is a volume of a part of the heating part through which the working fluid flows;
α g is a heat transfer coefficient of the heating fluid;
F w is a total sum of a heat transfer area between the heated fluid and the working fluid in the condensing part;
V w is a volume of a part of the condensing part in which the working fluid flows;
α w is a heat transfer coefficient of the heated fluid; and
V c is a volume of the storing part.

11. The exhaust heat recovery device according to claim 2 , wherein the storing part includes a condensed liquid holding part that holds the working fluid condensed by the condensing part.

12. The exhaust heat recovery device according to claim 2 , wherein:
the tube is one of a plurality of tubes;
the plurality of tubes includes fins respectively;
the fins accelerate a heat conduction between the heating fluid and the working fluid; and
the fins are not connected to each other.

13. The exhaust heat recovery device according to claim 12 , wherein each of the fins includes a curved surface having a shape of a circular arc projecting toward a lower side in the vertical direction.

14. The exhaust heat recovery device according to claim 2 , wherein:
the working fluid is water; and
the heating part, the condensing part, and the storing part are configured from a material that reacts with the working fluid to generate hydrogen gas when heated, the exhaust heat recovery device further comprising:
a heating fluid passage through which the heating fluid flows; and
a metal oxide receiving part in which metal oxide is enclosed and into which the hydrogen gas flows, wherein:
the metal oxide receiving part communicates with the condensing part; and
at least a part of the metal oxide receiving part is arranged in the heating fluid passage.

15. The exhaust heat recovery device according to claim 14 , further comprising a heat conduction limiting member between the heating part and the storing part, wherein:
the heat conduction limiting member limits a heat conduction from the heating fluid for the heating part to the working fluid in the storing part; and
the metal oxide receiving part is connected to the tube joint part and is arranged between the tube joint part and the heat conduction limiting member.

16. The exhaust heat recovery device according to claim 14 , wherein a part of the metal oxide receiving part is in contact with the heating fluid passage and another part of the metal oxide receiving part is in contact with outside air.

17. The exhaust heat recovery device according to claim 14 , further comprising a hydrogen gas introduction passage that is connected to an upper side of the condensing part in the vertical direction and introduces the hydrogen gas into the metal oxide receiving part.

18. An exhaust heat recovery device com

Assignees

• Denso Corp

Inventors

• Ueda Kenta
• Yamanaka Yasutoshi
• Kunikata Yuhei
• Mukoubara Yuuki
• Tamada Isao

Classifications

• F01K3/16 Primary

  Mutual arrangement of accumulator and heater · CPC title

• F01K11/00

  Plants characterised by the engines being structurally combined with boilers or condensers · CPC title

• F02G5/02 Primary

  Profiting from waste heat of exhaust gases · CPC title

• F01K23/10 Primary

  with exhaust fluid of one cycle heating the fluid in another cycle (F01K17/025 takes precedence) · CPC title

• F01K23/065

  the combustion taking place in an internal combustion piston engine, e.g. a diesel engine · CPC title