Underground heat-exchange system

Patent metadata

Field	Value
Publication number	US-2016209083-A1
Application number	US-201314913731-A
Country	US
Kind code	A1
Filing date	Nov 19, 2013
Priority date	Oct 8, 2013
Publication date	Jul 21, 2016
Grant date	—

Abstract

An underground heat exchange system is provided to reduce energy consumption for circulation of a heat transfer medium and reduce construction, management, and maintenance costs. The underground heat exchange system includes: a double-pipe heat exchanger that is buried underground to convert a heat transfer medium into a usable form; a medium collector that collects the heat transfer medium that has dispersed its heat via a heat consumption area to circulate the same to the ground heat exchanger; and a plurality of circulation loops. The medium collector includes first and second reservoirs that are arranged in two tiers: upper and lower, spaced apart from each other, an upstream pump is provided in a first circulation loop between the first and second reservoirs, and the second reservoir is placed higher than the first reservoir. The ground heat exchanger may enhance heat exchange efficiency by increasing the contact area and time between the ground and the heat transfer medium.

First claim

What is claimed is:

1 . An underground heat exchange system comprising:
a double-pipe heat exchanger that is buried underground to convert a heat transfer medium into a usable form; a medium collector that collects the heat transfer medium that has dispersed its heat via a heat consumption area to circulate the same to the ground heat exchanger; and a plurality of circulation loops, wherein the medium collector comprises first and second reservoirs that are arranged in two tiers which are upper and lower reservoirs that are spaced apart from each other, and wherein an upstream pump is provided in a first circulation loop between the first and second reservoirs, and the second reservoir is placed higher than the first reservoir.

2 . The underground heat exchange system of claim 1 , wherein the height difference between the first reservoir and the second reservoir is set taking the depth of the ground heat exchanger and the heat transfer rate into account.

3 . The underground heat exchange system of claim 1 , wherein an on-off valve is further provided in the second circulation loop between the second reservoir and the ground heat exchanger to adjust a water level or pressure of the second reservoir by means of the upstream pump.

4 . The underground heat exchange system of claim 3 , wherein a water level sensor is further provided at the second reservoir, and a controller is further provided among the upstream pump, on-off valve, and water level sensor to allow the upstream pump, on-off valve, and water level sensor to work in conjunction with one another.

5 . The underground heat exchange system of claim 1 , wherein an intermediate reservoir capable of storing the heat transfer medium that is converted into a usable form by the ground heat exchanger is further provided in the third circulation loop arranged between the ground heat exchanger and the heat consumption area.

6 . The underground heat exchange system of claim 5 , wherein the intermediate reservoir is placed higher than the first reservoir and lower than the second reservoir.

7 . The underground heat exchange system of claim 5 , wherein an extraction pump is further provided in the third circulation loop between the intermediate reservoir and the ground heat exchanger to extract the heat transfer medium from the ground heat exchanger.

8 . The underground heat exchange system of claim 1 , wherein the ground heat exchanger comprises:
an inner pipe that is connected to one end of the second circulation loop running from the second reservoir; an outer cylinder member that forms a double-pipe structure by the insertion and placement of the inner pipe, and that is open at one end and closed at the other to enable the heat transfer medium flowing along the outer surface of the inserted inner pipe to exchange heat with the ground; and a blocking cover that closes off the opening of the outer cylinder member, and that comprises a through hole for inserting the inner pipe and an extraction port for connecting to the third circulation loop leading to the heat consumption area.

9 . The underground heat exchange system of claim 8 , wherein the blocking cover further comprises: a fastening recess corresponding to the extremity of the opening of the outer cylinder member; and seals formed on every contact surface of the through hole to ensure water-tightness and air-tightness.

10 . The underground heat exchange system of claim 8 , wherein a fixing blade is further provided on the outer surface of the inner pipe so as to be held in place by being screwed onto a flange surface of the through hole of the blocking cover.

11 . The underground heat exchange system of claim 8 , wherein a flow rate reducing means for reducing the flow rate of the heat transfer medium is further provided either on the outer surface of the inner pipe inserted into the outer cylinder member or on the inner periphery of the outer cylinder member.

12 . The underground heat exchange system of claim 11 , wherein the flow rate reducing means is in the form of helical guide flanges or screw threads.

13 . The underground heat exchange system of claim 11 , wherein the flow rate reducing means further comprises collision members for creating a vortex in the heat transfer medium.

14 . The underground heat exchange system of claim 13 , wherein the collision members are protrusions or irregular bumps formed on the bottom or wall surface.

15 . The underground heat exchange system of claim 8 , wherein the outer cylinder member is divided into a blocking area where there is a need to block the heat transfer between the heat transfer medium and the ground, and an active area where there is a need to facilitate heat transfer between the heat transfer medium and the ground, depending on the depth to which the whole body is buried underground, and the blocking area and the active area are made of different materials with different thermal conductivity.

16 . The underground heat exchange system of claim 15 , wherein the blocking area of the outer cylinder member is 5 to 6 m deep from the opening.

17 . The underground heat exchange system of claim 16 , wherein the outer cylinder member is configured in such a way so as to wrap the outer surface of the blocking area with an insulation member.

Assignees

• Univ Seoul Ind Coop Found

Inventors

• Yu Byung Deok
• Min Hyunsoo
• Jeon Junjin

Classifications

• F24J3/081 Primary

  Mechanical Engineering · mapped topic

• F24J2003/087

  Mechanical Engineering · mapped topic

• F24J2003/089

  Mechanical Engineering · mapped topic

• F24T10/17 Primary

  using tubes closed at one end, i.e. return-type tubes · CPC title

• F24T2010/56

  Control arrangements · CPC title