KR20160004109A - Heat exchange apparatus for ship - Google Patents

Abstract

A heat exchange apparatus for a ship is disclosed. According to an embodiment of the present invention, the heat exchange apparatus for a ship comprises: a seawater channel which is formed by penetrating the bottom of a hull in a longitudinal direction; and a heat exchange part for cooling water which is arranged in the seawater channel and allows cooling water circulating in a cooling system for a ship to flow thereinto. Therefore, the present invention performs heat exchange between the cooling water and seawater outside the hull by exposing the heat exchange part for cooling water to the seawater.

Description

[0001] HEAT EXCHANGE APPARATUS FOR SHIP [0002]

The present invention relates to a ship heat exchanger.

Liquefaction installations may be provided in vessels, fixed platforms or floating offshore installations, eg LNG - FPSO (Liquefied Natural Gas - Floating Production Storage Offloading). In the cooling system of the liquefaction plant, fresh water is used as cooling water, and the heated cooling water is generally cooled by seawater. For this purpose, seawater is drawn into the hull through a sea chest installed under the hull. However, in the United States and Canada, where shale gas production is actively conducted in the recent years, for environmental reasons, it is prohibited to draw seawater into the hull to cool the cooling water. As a workaround, large air coolers may be installed on the upper part of the hull, but the efficiency of heat exchange may deteriorate, causing problems with ship stability and excessive drying cost.

The background art of the present invention is disclosed in Korean Patent Laid-Open Publication No. 10-2013-0049890 (Mar. 05, 201, Mud tank of drill ship).

It is an object of the present invention to provide a ship heat exchanger capable of performing heat exchange between cooling water and seawater outside the hull by exposing the cooling water heat exchanger to seawater without drawing seawater into the hull.

According to an aspect of the present invention, there is provided a watercraft comprising: a seawater channel formed through a lower portion of a hull in a longitudinal direction; And a cooling water heat exchanger disposed in the seawater channel and through which the cooling water circulating in the ship cooling system enters and exits.

The seawater channel includes: a first chamber formed at a lower portion of a bow of the hull; A second chamber formed under the stern of the hull; And two branch channels formed in the longitudinal direction of the lower portion of the hull and the lower portion of the starboard of the hull and connected to the first chamber at one end and the second chamber at the other end, Wherein the first chamber and the second chamber are formed with seawater exits and the first chamber and the second chamber may have a cross sectional area greater than the sum of the cross sectional areas of the two branch channels.

The two branch channels may be formed symmetrically with respect to the center line of the ship.

A variable propeller installed in the branch channel for controlling a flow rate of seawater passing through the branch channel; And a control unit for controlling the variable propeller.

A first sensor unit for sensing inflow temperature, outflow temperature and flow rate of seawater in the branch channel; And a second sensor unit for sensing an inflow temperature, an outflow temperature, and a flow rate of the cooling water in the cooling water heat exchanging unit, wherein the controller controls the first sensor unit and the second sensor unit, The flow rate of the seawater passing through the branch channel can be controlled by controlling the variable propeller so that the outflow temperature of the seawater is less than a predetermined value.

The variable propeller can adjust the direction in which the seawater passes through the branch channel.

According to the embodiments of the present invention, by arranging the cooling water heat exchanger in the sea water channel formed through the hull in the longitudinal direction, the cooling water heat exchanger is exposed to seawater without drawing seawater into the hull, Can be performed. As a result, it is possible to avoid the restrictions of some countries prohibiting the cooling of cooling water by drawing seawater into the hull, and it is possible to secure the appropriate level of heat exchange efficiency required for the ship cooling system.

1 is a schematic view of a ship heat exchanger according to an embodiment of the present invention.
Fig. 2 is a sectional view taken along the line I-I 'in Fig.
3 is a view showing a control unit.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Hereinafter, preferred embodiments of a ship heat exchanger according to the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals designate like or corresponding components, A duplicate description will be omitted.

FIG. 1 is a schematic view of a ship heat exchanger according to an embodiment of the present invention. FIG. 2 is a sectional view taken along line I - I 'of FIG. 1, and FIG. 3 is a view showing a control unit.

1 to 3, a ship heat exchanger according to an embodiment of the present invention includes a seawater channel 100, a cooling water heat exchanger 200, a variable propeller 300, a first sensor unit 400, A second sensor unit 500 and a control unit 600. [

The seawater channel 100 may be formed through the hull 10 in the longitudinal direction of the ship.

That is, the sea water outlets 111 and 121 of the sea water channel 100 may be formed on the fore and aft foreheads of the hull 10, respectively. As a result, seawater can be naturally introduced into the sea water channel 100 during ship operation.

The seawater channel 100 may be formed at the bottom of the hull 10 so as to be always immersed in seawater.

The seawater channel 100 may include a first chamber 110, a second chamber 120, a first branch channel 130, and a second branch channel 140.

The first chamber 110 may be formed at the lower portion of the bow of the hull 10.

A first seawater inlet / outlet 111 may be formed in the front side of the bow of the first chamber 110.

The seawater can pass between the outside of the hull 10 and the first chamber 110 through the first seawater inlet / outlet 111.

The second chamber 120 may be formed below the stern of the hull 10.

A second seawater inlet / outlet 121 may be formed on the aft side of the second chamber 120.

The seawater can pass between the outside of the hull 10 and the second chamber 120 through the second seawater inlet 121.

The first branch channel 130 may be formed in the longitudinal direction of the ship at the port downstream of the hull 10.

The second branch channel (140) may be formed in the longitudinal direction of the ship at the bottom of the starboard of the ship (10).

The first branch channel 130 may connect the first chamber 110 and the second chamber 120, and the cooling water heat exchanging part 200 may be disposed therein. Similarly, the second branch channel 140 may connect the first chamber 110 and the second chamber 120, and the cooling water heat exchanger 200 may be disposed therein.

The first chamber 110, the second chamber 120, the first branch channel 130 and the second branch channel 140 are formed under the hull 10 so that the upper space is filled with a ballast tank .

The space of the hull 10 between the first branch channel 130 and the second branch channel 140 can be utilized as a cargo window, a machine room, and the like.

The first branch channel 130 and the second branch channel 140 may be formed symmetrically with respect to the center line C of the ship. As a result, torque is generated due to the seawater passing through the first branch channel 130 and the second branch channel 140, thereby preventing the hull 10 from rotating.

The cross sectional area of the first chamber 110 may be greater than the sum of the cross sectional areas of the first branch channel 130 and the second branch channel 140. Similarly, the cross-sectional area of the second chamber 120 may be greater than the sum of the cross-sectional areas of the first branch channel 130 and the second branch channel 140. As a result, the flow velocity of the seawater flowing into the first branch channel 130 and the second branch channel 140 is greater than the flow velocity of the seawater flowing into the first chamber 110 or the second chamber 120, The heat exchange efficiency can be improved in the cooling water heat exchanger 200 disposed in the first branch channel 130 and the second branch channel 140. [ In addition, when sea water is forced to flow into the first branch channel 130 and the second branch channel 140 by the variable propeller 300 at the time of berth, the first chamber 110 or the second chamber 120 is filled with seawater It is possible to prevent an excessive flow field from being formed around the ship.

The cooling water heat exchanger 200 may be disposed in the seawater channel 100, specifically, the first branch channel 130 and the second branch channel 140, respectively.

The cooling water heat exchanging part 200 may include a plurality of pipes through which cooling water flows.

The cooling water, for example, fresh water, is circulated in the ship cooling system 20 mounted on the ship and can enter and exit the cooling water heat exchanging part 200 to be maintained at a predetermined temperature or lower.

The ship cooling system 20 means a facility used to lower the temperature of a cooling target material, for example a shale gas, in a heating device in a ship, for example, a liquefaction facility.

The variable propeller 300 may be disposed in the first branch channel 130 and the second branch channel 140, respectively.

The variable propeller 300 may control the flow rate through the first branch channel 130 and the second branch channel 140 by being controlled by the controller 600. [

For example, when the demand for heat exchange is small in the cooling water heat exchanging part 200, the control part 600 can operate the variable propeller 300 at a slow speed or operate at a slow speed, If the exchange demand is high, the variable propeller 300 will be able to operate at a high speed.

The variable propeller 300 may adjust the direction in which the seawater passes through the first branch channel 130 and the second branch channel 140.

For example, the variable propeller 300 may flow seawater from the first chamber 110 to the second chamber 120 or from the second chamber 120 to the first chamber 110. As a result, the variable propeller 300 can adjust the direction in which the seawater enters and exits according to the external environment of the ship, so that the problem does not occur near the ship due to seawater entering and exiting the seawater channel 100.

For this purpose, the variable propeller 300 can be switched in the direction of rotation or can be arranged at each end of the branch channels 130 and 140, respectively. The variable propeller 300 may be disposed at each of the opposite ends of the branch channels 130 and 140 in preparation for failure.

The first sensor unit 400 can sense the inflow temperature, the outflow temperature, and the flow rate of the seawater in the branch channels 130 and 140.

The inflow temperature of the seawater sensed by the first sensor unit 400 is determined by the temperature of the seawater at the point where the seawater flows into the branch channels 130 and 140 and the temperature of the outflow of the seawater from the branch channels 130 and 140 The flow rate of the seawater is the flow rate of the seawater passing through the branch channels 130 and 140, respectively.

The second sensor unit 500 can sense the inflow temperature, the outflow temperature, and the flow rate of the cooling water in the cooling water heat exchanging unit 200.

The inlet temperature of the cooling water sensed by the second sensor unit 500 is determined by the temperature of the cooling water at the point 201 where the cooling water flows into the cooling water heat exchanging unit 200 and the outlet temperature of the cooling water is the cooling water heat exchanging unit 200, and the flow rate of the cooling water refers to the flow rate of the cooling water passing through the cooling water heat exchanging part 200, respectively.

The results sensed by the first sensor unit 400 and the second sensor unit 500 may be transmitted to the controller 600.

The control unit 600 may control the variable propeller 300 according to the results detected by the first sensor unit 400 and the second sensor unit 500. [

Specifically, the control unit 600 controls the rotation speed of the variable propeller 300 such that the outflow temperature of the seawater is equal to or lower than a predetermined value, for example, 50 ° C or lower and the outflow temperature of the cooling water is equal to or lower than a predetermined value, So that the flow rate of the seawater passing through the branch channels 130 and 140 can be controlled.

If the temperature of seawater exceeds 50 ℃, chlorine gas, which can cause environmental pollution in seawater, may be generated. Therefore, it is necessary to control the outflow temperature of seawater to 50 ℃ or less.

It is necessary to control the outflow temperature of the cooling water, that is, the temperature at which the cooling water is introduced into the ship cooling system 20 to a maximum temperature for performing the function in the ship cooling system 20, for example, 36 ° C or less.

The flow rate of seawater passing through the branch channels (130, 140) can be derived from the following equation.

(Equation)

In the equation m _sw is the sea water (mass) flow rate, m _cw is (mass) flow rate of cooling water, C _{p, sw} is a specific heat of water, C _{p, cw} is specific heat of the cooling water, T _{i, sw} is the sea water inlet temperature, T _{o, sw} is the water outlet temperature, T _{i, cw} is the inlet temperature of the cooling water, T _{o, cw} means the outlet temperature of the cooling water, respectively.

And C _{p, sw} and C _{p, cw} is the unique properties of each water and the cooling water, T _{o, sw} is 50 _℃, T _{o, cw} because it is subject to each set to 36 ℃, a first sensor unit 400 T _{i , sw} are detected by the second sensor unit 500, respectively, m _sw can be calculated from the above equation by detecting T _{i , c w,} and m _cw .

The control unit 600 may control the rotational speed of the variable propeller 300 so that the flow rate of the seawater satisfies m _sw calculated in the above equation.

The reason why the first sensor unit 400 senses the outflow temperature of the seawater is to check whether the outflow direction of the seawater can be changed by the variable propeller 300 and the outflow temperature of the seawater is below 50 ° C. Likewise, the reason why the second sensor unit 500 senses the outflow temperature of the cooling water is to check whether the outflow temperature of the cooling water is 36 캜 or less. The control unit 600 may increase the rotation speed of the variable propeller 300 if the outflow temperature of the seawater or the cooling water does not become the preset value or less.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit of the invention as set forth in the appended claims. The present invention can be variously modified and changed by those skilled in the art, and it is also within the scope of the present invention.

10: Hull 20: Ship Cooling System
100: sea water channel 110: first chamber
111: First sea water inlet / outlet 120: Second chamber
121: second seawater entrance 130: first branch channel
140: second branch channel 200: cooling water heat exchanger
300: variable propeller 400: first sensor unit
500: second sensor unit 600:

Claims (6)

A seawater channel formed through a lower portion of the hull in a longitudinal direction; And
And a cooling water heat exchanger disposed in the seawater channel for allowing cooling water circulating in the ship cooling system to flow in and out. The method according to claim 1,
Wherein the seawater channel comprises:
A first chamber formed at a lower portion of the bow of the hull;
A second chamber formed under the stern of the hull; And
Two branch channels formed longitudinally in the lower portion of the hull and the lower portion of the starboard of the hull and connected to the first chamber at one end and the second chamber at the other end, Including,
Wherein the first chamber and the second chamber are formed with seawater entrances,
Wherein the first chamber and the second chamber have a cross sectional area larger than the sum of the cross sectional areas of the two branch channels. 3. The method of claim 2,
Wherein the two branch channels are formed symmetrically with respect to the center line of the ship. The method according to claim 2 or 3,
A variable propeller installed in the branch channel for controlling a flow rate of seawater passing through the branch channel; And
And a control unit for controlling the variable propeller. 5. The method of claim 4,
A first sensor unit for sensing inflow temperature, outflow temperature and flow rate of seawater in the branch channel; And
And a second sensor unit for sensing an inflow temperature, an outflow temperature and a flow rate of the cooling water in the cooling water heat exchanging unit,
Wherein the control unit controls the variable propeller so that the outflow temperature of the seawater and the cooling water is less than a preset value according to a result sensed by the first sensor unit and the second sensor unit to control the flow rate of the seawater passing through the branch channel A heat exchanger for ships. 5. The method of claim 4,
Wherein the variable propeller adjusts the direction in which the seawater passes through the branch channel.

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