KR100720819B1 - Calculation for heating coil length in Tankers - Google Patents

Abstract

Disclosed is a method for calculating a heating coil length of a tank in a ship considering ship operating conditions. The method for calculating a heating coil length in consideration of the vessel operating condition may include selecting a tank in a vessel in which the heating coil is to be installed and inputting data necessary for sailing the vessel and basic information of the vessel (S1); Calculating an effective temperature difference (LMTD) between the heat source of the heating coil and the cargo, and calculating a total amount of Q _heating required to increase the temperature of the cargo (S2); Calculating a heating coil internal heat transfer coefficient h _i , preliminarily setting the length L of the heating coil to calculate an external heat transfer coefficient h _o , and calculating a total heat transfer coefficient U _coil of the heating coil (S3). ); Calculating an amount of heat loss (Q _loss ) of cargo in the tank and a _total amount of heat (Q _total ) required for cargo temperature rise and heat loss replenishment (S4); Calculating a total length L _coil of the heating coil by calculating a total heat transfer area A _coil of the heating coil required for cargo temperature rise and heat loss replenishment (S5); Compared with the total length L of the heating coil and the total length L of the _preset heating coil, the result is output if the length is the same, and if the length is not the same, until the length is the same. After repeating the steps S3 to S5 and outputs a result (S6).

Cargo tank, heating coil heat transfer area, ship, total heat transfer coefficient, heat loss

Description

Calculation method of heating coil length in consideration of ship operating conditions {Calculation for heating coil length in Tankers}

1 illustrates the shape and heat loss area of a wing tank among tanks applicable to a cargo tank of a ship.

Figure 2 shows the shape and heat loss area of the center tank of the tank applicable to the cargo tank of the ship.

Figure 3 shows the shape and heat loss area of the side tank of the tank applicable to the cargo tank of the ship.

Figure 4 illustrates the shape and heat loss area of the ballast tank of the tank applicable to the cargo tank of the ship.

5 is an optimal design code flow diagram of the cargo tank heating system.

6 is a flow chart of heat loss calculation at the deck of the wing tank.

7 is a flow chart for calculating heat loss to the atmosphere through the air layer of the side ballast tank.

8 is a flow chart of heat loss calculation from the lateral ballast tank to the sea channel.

9 is a flow chart for calculating heat loss at the bottom of the vessel.

10 is a layout of a heating coil in a cargo tank of a typical ship.

The present invention is a method for calculating the length of the heating coil required in the tank of the vessel by the operating area of the vessel, the speed of the vessel, the type of cargo, the automatic calculation of the required length of the heating coil by the respective input conditions The present invention relates to a method of calculating the length of a heating coil in consideration of ship operating conditions, which can standardize various types of ships, thereby preventing waste of materials and reducing labor.

In general, all vessels are equipped with steam producing boilers. Referring to Figure 10 the structure of the boiler for producing steam as follows. FIG. 10 is a view illustrating a heating coil arrangement in a cargo tank of a conventional ship, and as illustrated in FIG. 10, a tanker ship maintains a constant temperature to pump cargo. Install a heating coil in the cargo tank. The structure of the heating coil is composed of the main pipe for supplying steam from the boiler, the heating coil to increase the cargo temperature, the condensate pipe back to the boiler, the heating coil is about 30cm above the bottom of the tank horizontally 'U' It is connected in the form of a child.

The heating coil installed as described above is typically calculated by simply calculating the length of the heating coil in accordance with the Heat Calculation formula of the Japanese Ship Design Standard (JSDS) without thorough examination of the ship operating conditions in the ship design. Unnecessarily excessively calculated length of unnecessary air consumption and materials are consumed, or the length of the heating coil below the appropriate level is calculated to meet the needs of the ship owners, and also, the ship specifications and operating conditions for each ship construction There is a problem that the amount of work of the designer is increased by manually calculating the length of the matching heating coil.

Therefore, an object of the present invention is to calculate the length of the heating coil of the appropriate level required by the vessel according to the operating area of the vessel, the speed of the vessel, the type of cargo, the standardization of various types of vessels can be standardized for the length of the heating coil It is to provide a method of calculating the length of the heating coil in consideration of the ship operating conditions that can be overestimated unnecessarily to avoid unnecessary waste of air and material consumption, and satisfactorily meet the needs of the user.

In order to achieve the above object, the present invention relates to a method for calculating the length of a heating coil installed to maintain a constant temperature so as to pump cargo in a cargo tank of a ship using a known computer system equipped with an input device. The method may include: inputting information of a tank in a ship to which a heating coil is to be installed, data necessary for voyage of the ship and basic information of the ship to the computer system through an input device of the computer system (S1); Using the data input in the step S1 to calculate the effective temperature difference (LMTD) between the heat source of the heating coil and the cargo in the central processing unit of the computer system, and calculates the amount of heat (Q _heating ) required to increase the temperature of the cargo Step S2; The heating coil internal heat transfer coefficient h _i is calculated by the central processing unit of the computer system using the data input in the step S1, and the external heat transfer coefficient h _o is calculated by temporarily setting the length L of the heating coil. Calculating a total heat transfer coefficient (U _coil ) of the heating coil (S3); Using the data input in step S1, the central processing unit of the computer system calculates the heat loss amount (Q _loss ) of cargo in the tank, and calculates the _total heat quantity (Q _total ) required for the cargo temperature rise and heat loss replenishment. Step S4; Cargo temperature rise and heat loss in the central processing unit of the computer system using the effective temperature difference (LMTD) of step S2, the overall heat transfer coefficient (U _coil ) of step S3 and the _total heat transfer amount (Q _total ) of step S4. Calculating a total heat transfer area A _coil of the heating coil required for replenishment, and calculating a total length L _coil of the heating coil (S5); The total length L of the heating coil of step S5 and the total length L of the _preset heating coil of step S3 are compared by the central processing unit of the computer system, and the result is output when the lengths are the same. , If the length is not equal to the heating coil length calculation method in consideration of the ship operating conditions consisting of the step (S6) of repeatedly outputting the result after the step S3 to S5 until the length is the same.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 shows the shape and heat loss area of the wing tank of the tank applicable to the cargo tank of the ship, A1 represents the heat loss area through the deck, A2 is through the air layer of the ballast (Ballast) tank A3 represents the heat loss area to the atmosphere, A3 represents the heat loss area to the sea through the air layer of the ballast tank, A4 represents the heat loss area to the sea through the air layer of the bottom ballast, and A5, A6, A7 The heat loss area to the rounding tank is shown.

Figure 2 shows the shape and heat loss area of the center tank of the tank applicable to the cargo tank of the ship, A1 represents the heat loss area through the deck, A3 is the heat to the sea through the air layer of the bottom ballast Loss area, A2, A4, A5, A6 represents the heat loss area to the surrounding tank.

Figure 3 shows the shape and heat loss area of the side tank of the tank applicable to the cargo tank of the ship, A1 shows the heat loss area through the deck, A2 is the heat loss to the atmosphere through the vertical wall surface A3 is the area of heat loss to the sea through the vertical wall, A4 is the area of heat loss to the sea through the air layer of the bottom ballast, and A5, A6, A7 is the area to the surrounding tank. It shows the heat loss area.

In addition, Figure 4 shows the shape and heat loss area of the ballast tank of the tank applicable to the cargo tank of the ship, A1 shows the heat loss area through the deck, A2 is the heat to the atmosphere through the vertical wall Loss area, A3 is the heat loss area to the sea through the vertical wall, A4 is the heat loss area to the sea through the bottom, and A5, A6 is the heat inflow area to the cargo tank. A7 and A8 represent the heat loss area to the surrounding tank.

In one embodiment according to the present invention of the heating coil for the wing (wing) tank shown in Figure 1 of the type of tank that can be applied to the cargo (Cargo) tank of all ships as shown in Figure 1 to Figure 4 The calculation method is explained with an example.

FIG. 5 is a flowchart illustrating an optimal design code of a cargo tank heating system. As shown in FIG. 5, in step S1, a heating coil of a wing tank, a center tank, a side tank, and a ballast tank provided in the vessel is installed. Selecting at least one inner tank, in one embodiment according to the invention is selected a wing tank as shown in FIG.

As described above, a wing tank, which is a tank in which the heating coil is to be installed, is selected, and in step S1, data necessary for sailing the vessel and basic information of the vessel are input. The necessary data for the navigation of the vessel is the temperature conditions of the operating region, the wind around the vessel, the vessel navigation speed and the basic information of the vessel is a heat source injected into the vessel heating coil, the type of cargo loaded in the vessel tank, the heating coil Material, diameter, and size of the tank by the basic design.

In addition, as a heat source injected into the ship heating coil can be used to select hot water, hot oil, steam, etc., the above data is input through the input device of a known computer system, each step described below is Although not shown, it will be apparent to those skilled in the art that the software is executed by the central processing unit of the computer system having the input device.

In the step S2, the effective temperature difference LMTD between the heat source of the heating coil and the cargo is calculated by the central processing unit of the known computer system using the data input in the step S1.

That is, LMTD, which is an effective temperature difference between the heat source of the heating coil and Cargo,

..................................식 1

Equation 1

Wherein, T1 is the steam temperature inside the heating coil, t1 is the initial cargo temperature, T2 is the condensation temperature inside the heating coil, t2 is the cargo final temperature.

In step S2, the amount of Q _heating required to increase the cargo temperature is calculated by the central processing unit of the computer system using the data input in step S1.

That is, if the amount of heat required to increase the temperature of the cargo (Cargo) is Q _heating ,

............................ 식2

Equation 2

은 탱크 내부의 카고 체적 (㎥)이고,

는 카고의 비중 (kg/㎥)이며,

는 카고의 비열 (kcal/kg℃)이고,

는 가열시간 (hr)을 나타낸다.Can be expressed as

Is the cargo volume (m 3) inside the tank,

Is the specific gravity of the cargo (kg / ㎥),

Is the specific heat of cargo (kcal / kg ° C),

Denotes a heating time (hr).

In step S3, the heating coil internal heat transfer coefficient h _i is calculated using the data input in step S1, which is a capacity of the heat source inside the heating coil to transfer heat in the central processing unit of the computer system.

The heat transfer coefficient h _i inside the coil when using a heat source of hot water and hot oil can be calculated by Equation 3 to be described later.

.................................. 식3

Equation 3

는 가열 코일의 내부직경, k는 가열 코일의 열전도율, Pr은 Prandtl number, Re는 열원의 Reynolds number이며 다음과 같다.here,

Is the inner diameter of the heating coil, k is the thermal conductivity of the heating coil, Pr is the Prandtl number, and Re is the Reynolds number of the heat source.

................................ 식3a

Equation 3a

(kg/㎡hr)는Heat source mass flow rate in coil

(kg / ㎡hr) is

.................................... 식3b

Equation 3b

는 열원 소비량 (kg/hr)을 나타내며,

Represents heat source consumption (kg / hr),

.................................... 식3c

Equation 3c

When using a steam heat source, the coil internal heat transfer coefficient h _i may be calculated by Equation 4 to be described later.

......................................... 식4

Equation 4

Here, Re is Reynolds number of steam, and the following equation 4a.

................................................식4a

Equation 4a

In step S3, the length L of the heating coil to be installed in the tank in the ship is temporarily set, and in the central processing unit of the computer system using the data input in the step S1 and the length L of the preset heating coil. An external heat transfer coefficient h _o , which is the ability of the cargo outside the coil to receive heat, is calculated.

Since the cargo is stagnant in the tank, the heat transfer coefficient outside the heating coil depends on the natural convection heat transfer coefficient, and since the heating coil is installed as a horizontal heat transfer tube, Using McAdams' theory, the external heat transfer coefficient h _o is

...................................... 식5

Equation 5

Where Gr is the Grashof number,

...................................... 식5a

Equation 5a

It can be calculated by, β is expansion coefficient (Expansion Coe, 1 / ℃),

...................................... 식5b

Equation 5b

Where Pr is the Prandtl number,

................................................ 식5c

Equation 5c

는 카고의 비열이다.Can be calculated by

Is the specific heat of cargo.

The constant c and the index n follow Table 1.

Flow format Range of Gr / Pr c n Laminar Flow 10 ^{9 4-10} 0.53 1/4 turbulence 10 ^{9-10 13} 0.13 1/3

Table 1

In the step S3, the overall heat transfer coefficient of the heating coil in the central processing unit of the computer system using the data input in the step S1 and the calculated internal heat transfer coefficient h _i and the calculated external heat transfer coefficient h _o . Calculate (U _coil ).

(kcal/㎡hr℃)는 다음과 같다.That is, overall heat transfer coefficient of heating coil

(kcal / m 2 hr ° C) is as follows.

..............................식6

Equation 6

는 가열 코일의 외부직경(Outside diameter of heating coil)(m)이고,

는 가열 코일의 내부직경(Inside diameter of heating coil)(m)이며, k는 가열 코일의 열전도율(Thermal conductivity of heating coil(kcal/mhr℃)이고,

는 가열 코일의 내부 오염계수(Inside fouling factor of heating coil)(㎡hr℃/kcal)이며,

는 가열 코일의 외부 오염계수(Outside fouling factor of heating coil)(㎡hr℃/kcal)이다. here,

Is the outside diameter of heating coil (m),

Is the inner diameter of the heating coil (m), k is the thermal conductivity of the heating coil (kcal / mhr ℃),

Is the inside fouling factor of heating coil (㎡hr ° C / kcal),

Is the outside fouling factor of heating coil (m 2 hr / kcal).

In step S4 in the central processing unit of the computer system to calculate the respective wall by the heat loss of the data to the selected tank type in the step S1 to calculate the heat loss (Q _loss) of the cargo in the tank. That is, as shown in Figure 1, the heat loss amount for each wall surface of the wing tank is the heat loss amount (Q ₁ ) through the heat loss area (A1) through the deck, the heat loss area to the atmosphere through the air layer of the ballast tank ( A2) heat loss amount (Q ₂ ), ballast tank heat loss to sea through air layer (A3) heat loss amount (Q ₃ ), bottom ballast tank heat loss area to sea through air layer (A4) Heat loss amount (Q ₄ ) through (), heat loss amount (Q ₅ , Q ₆ , Q ₇ ) through the heat loss area (A5, A6, A7) to the surrounding tank, the amount of heat loss of cargo in the wing tank (Q _loss ) is equal to the sum of the heat losses of the respective wall surfaces (Q ₁ + Q ₂ + Q ₃ + Q ₄ + Q ₅ + Q ₆ + Q ₇ ).

Looking at the process of calculating the overall heat transfer coefficient and the heat loss amount in the deck with reference to Figure 6 as follows. FIG. 6 is a flowchart illustrating a heat loss calculation in a deck of a wing tank, and as shown in FIG. 6, the heat loss in the deck is determined by the wind speed outside the deck after assuming a temperature at the deck surface. The heat flux by forced convection is calculated, and the heat flux by natural convection by cargo is then calculated in the deck of the wing tank. Comparing the heat flux by the forced convection and the heat flux by the natural convection by the cargo computed above, the said deck surface until the heat flux by the forced convection and the heat flux by the natural convection by the cargo become equal After the temperature is continuously changed, the deck surface temperature is determined when the same heat is applied, the overall heat transfer coefficient at the deck is calculated, and the amount of heat loss at the deck is calculated.

)은Heat loss from deck

)silver

........................................... 식 7

Equation 7

은 갑판에서의 총괄 전열계수,

은 갑판에서 열손실 면적(㎡)이며,ΔT₁은 최고 오일상승 온도와 대기온도차(℃)이다.here,

Is the overall heat transfer coefficient at deck,

Is the heat loss area in m 2 of the deck, and ΔT ₁ is the maximum oil rise and atmospheric temperature difference in ° C.

In addition, the process of calculating the heat loss amount to the atmosphere through the air layer of the ship side ballast tank of the wing tank will be described with reference to FIG. FIG. 7 is a flowchart illustrating the heat loss calculation to the atmosphere through the air layer of the ship side ballast tank, and as shown in FIG. 7, the heat loss amount to the atmosphere through the air layer of the ship side ballast tank of the wing tank is shown in FIG. 7. After assuming the internal air temperature, the forced convection heat flux due to wind speed is calculated, the natural convection heat flux in the cargo tank is calculated, and the heat flux due to forced convection and the natural flux in the cargo tank are the same. The assumed ballast tank internal air temperature is continuously changed until it is lost, the air temperature inside the ballast tank is determined when the same heat flux is obtained, and the ship side overall heat transfer coefficient is calculated. Calculate the heat loss of.

)은Heat loss to the atmosphere through the air layer of the ballast tank (

)silver

............................................. 식 8

Equation 8

는 밸러스트 탱크의 공기층을 통한 대기로의 열손실에서 총괄전열계수,

는 밸러스트 탱크의 공기층을 통한 대기로의 열손실 면적(㎡)이며,△T₂는 최고 오일상승 온도와 대기온도차(℃)이다.here,

Is the overall heat transfer coefficient at heat loss to the atmosphere through the air layer of the ballast tank,

Is the heat loss area (m 2) to the atmosphere through the air layer of the ballast tank, and ΔT ₂ is the maximum oil rise temperature and the air temperature difference (° C.).

In addition, the process of calculating the heat loss amount from the ship side ballast tank of the wing tank to the sea channel will be described with reference to FIG. 8 is a flowchart illustrating the heat loss calculation from the ship side ballast tank to the seawater channel, and as shown in FIG. 8, the heat loss amount from the ship side ballast tank of the wing tank to the seawater channel is assumed after the air temperature inside the ballast tank. Calculate the forced convection heat flux due to the double speed, calculate the natural convection heat flux in the cargo tank, and then assume the above assumptions until the forced convection heat flux due to the double speed and the heat flux due to natural convection in the cargo tank are equal. The air temperature inside the ballast tank is continuously changed to determine the air temperature inside the ballast tank when the same heat flux is obtained, and then the ship's total heat transfer coefficient is calculated, and then the amount of heat loss to the ship's atmosphere is calculated. .

........................................... 식 9

Equation 9

는 밸러스트 탱크의 공기층을 통한 바다로의 열손실에서 총괄전열계수,

는 상기 밸러스트 탱크의 공기층을 통한 바다로의 열손실 면적(㎡)이며, △T₃는 최고 오일상승 온도와 해수 온도차(℃)이다.here,

Is the overall heat transfer coefficient at heat loss to the sea through the air layer of the ballast tank,

Is the heat loss area (m 2) to the sea through the air layer of the ballast tank, and ΔT ₃ is the maximum oil rise temperature and the seawater temperature difference (° C.).

In addition, the process of calculating the heat loss amount from the bottom of the ship of the wing tank is described with reference to FIG. 9 is a flowchart illustrating the heat loss calculation at the bottom of the ship. As shown in FIG. 9, the heat loss at the bottom of the wing tank is assumed to be forced convection by the speed of the ship after assuming the air temperature in the ballast tank. Calculate the heat flux by the airflow, calculate the heat flux by the natural convection by the cargo, and then the assumed ballast until the forced convection heat flux due to the ship's speed is equal to the heat flux by the natural convection in the cargo tank. The air temperature in the ballast tank is determined by continuously changing the air temperature inside the tank to determine the ballast tank air temperature when the same heat flux is obtained, and then calculating the total heat transfer coefficient at the bottom of the ship, and then the amount of heat loss from the bottom of the ship to the seawater of the ballast tank. To calculate.

.......................................... 식 10

Equation 10

는 배 밑바닥 밸러스트 탱크의 공기층을 통한 바다로의 열손실에서 총괄전열계수,

는 배 밑바닥 밸러스트 탱크의 공기층을 통한 바다로의 열손실 면적(㎡)이고, △T₄는 최고 오일상승 온도와 해수 온도차(℃)이다.here

Is the overall heat transfer coefficient from the heat loss to the sea through the air layer of the ship's bottom ballast tank,

Is the heat loss area (m 2) to the sea through the air layer of the ship's bottom ballast tank, and ΔT ₄ is the maximum oil rise temperature and seawater temperature difference (° C).

In the process of calculating the heat loss amount of the surrounding tank to the air layer, the heat loss amount of the surrounding tank to the air layer is assumed to be the temperature at the surface of the separator plate of the surround and cargo tanks, and then the outside of the separator plate (surround The heat flux by natural convection by the air layer in the tank) is calculated, and the heat flux by natural convection by cargo is then calculated inside the separator plate (in the cargo tank). Comparing the heat flux due to natural convection with air and the heat flux due to natural convection with cargo calculated above, until the heat flux due to natural convection of air is equal to the heat flux due to natural convection of cargo. The assumed separator surface temperature is continuously changed to determine the separator plate temperature when the same heat flux is obtained, and then the overall heat transfer coefficient to the air layer of the surrounding tank is calculated, and then to the air layer of the surrounding tank. Calculate the heat loss of.

............................................ 식 11

Equation 11

써라운딩 탱크의 공기층으로의 열손실에서 총괄전열계수,

는 써라운딩 탱크의 공기층으로의 열손실 면적(㎡)이고, △T₅는 최고 오일상승 온도와 공기 온도차(℃)이며,

,

또한 상기

와 동일한 방법으로 산출할 수 있다.here,

Overall heat transfer coefficient from heat loss to the air layer of the surrounding tank,

Is the heat loss area to the air layer of the surrounding tank (㎡), ΔT ₅ is the maximum oil rise temperature and the air temperature difference (℃),

,

Also above

It can be calculated in the same way as.

는 상기에서 산출된 열손실량의 합으로 나타낼 수 있다. 즉

는,Heat loss of cargo in the cargo tank

Can be expressed as the sum of the heat losses calculated above. In other words

Is,

..................... 식 12

Equation 12

It can calculate by

)과 열손실량(

)을 이용하여 상기 컴퓨터 시스템의 중앙처리 장치에서 카고(Cargo) 온도 상승 및 열손실 보충에 필요한 전체 전열량(

)을 산출한다. 즉

은,In step S4, the amount of heat required to increase the temperature of the cargo calculated in step S2 (

) And heat loss

Total heat transfer amount required for cargo temperature rise and heat loss replenishment in the central processing unit of the computer system.

) Is calculated. In other words

silver,

=

+

....................................식 13

=

+

Equation 13

It can calculate by

) 상기 S3단계에서 산출된 총괄 전열 계수(

) 및 상기 S2단계에서 산출된 가열 코일의 열원과 카고와의 유효 온도차(

)를 이용하여 상기 컴퓨터 시스템의 중앙처리 장치에서 카고 온도 상승 및 열손실 보충에 필요한 가열 코일의 전체 전열 면적(

)을 산출한다.In step S5 and the total amount of heat required to increase the cargo temperature and heat loss calculated in step S4 and (

) The overall heat transfer coefficient calculated in step S3 (

) And the effective temperature difference between the heat source and the cargo of the heating coil calculated in step S2 (

), The total heat transfer area of the heating coil required for cargo temperature rise and heat loss

) Is calculated.

=

+

와

=

*

*

에 의해서, 가열 코일의 전열 면적

은 다음과 같다. In other words,

=

+

Wow

=

*

*

By heat transfer area of heating coil

Is as follows.

=

/

*

.............................. 식 14

=

Of

*

Equation 14

이므로, 가열 코일의 전체길이는

은 다음과 같다.Also,

Therefore, the overall length of the heating coil

Is as follows.

...................................... 식 15

Equation 15

)와 상기 S3단계에서 가설정된 가열 코일의 전체 길이(L)를 상기 컴퓨터 시스템의 중앙처리 장치에서 비교하여 그 길이가 같은 경우에는 결과를 출력하며, 그 길이가 같지 않을 경우에는 그 길이가 같아질 때까지 상기 S3단계부터 S5단계를 반복 실행한 후 결과를 출력한다.In step S6 the total length of the heating coil calculated in step S5 (

) And the total length L of the heating coil set in step S3 are compared in the central processing unit of the computer system, and the result is output if the length is the same, and the length is the same if the length is not the same. Repeat step S3 to step S5 until the output and then output the result.

The present invention is not limited to the above-described specific preferred embodiments, and various modifications can be made by any person having ordinary skill in the art without departing from the gist of the present invention claimed in the claims. Of course, such changes will fall within the scope of the claims.

As described above, in the method of calculating the length of the heating coil in consideration of the ship operating conditions according to the present invention, the length of the heating coil of an appropriate level required for the corresponding ship is calculated according to the ship's operating area, the speed of the ship, and the type of cargo. By this, standardization of various vessels is possible, the length of the heating coil is unnecessarily overcalculated to prevent unnecessary air consumption and material consumption, and the appropriate level of heating coil can be manufactured to satisfy the user's needs as well. It is a very useful invention to improve the work efficiency by reducing the workload of the designer.

Claims (2)

In the method for calculating the length of the heating coil which is installed to maintain a constant temperature so as to pump the cargo in the cargo tank of the ship using a known computer system equipped with an input device, Inputting information of a tank in a ship to which a heating coil is to be installed, data necessary for voyage of the ship, and basic information of the ship to the computer system through an input device of the computer system (S1); Using the data input in the step S1 to calculate the effective temperature difference (LMTD) between the heat source of the heating coil and the cargo in the central processing unit of the computer system, and calculates the amount of heat (Q _heating ) required to increase the temperature of the cargo Step S2; The heating coil internal heat transfer coefficient h _i is calculated by the central processing unit of the computer system using the data input in the step S1, and the external heat transfer coefficient h _o is calculated by temporarily setting the length L of the heating coil. Calculating a total heat transfer coefficient (U _coil ) of the heating coil (S3); Using the data input in step S1, the central processing unit of the computer system calculates the heat loss amount (Q _loss ) of cargo in the tank, and calculates the _total heat quantity (Q _total ) required for the cargo temperature rise and heat loss replenishment. Step S4; Cargo temperature rise and heat loss in the central processing unit of the computer system using the effective temperature difference (LMTD) of step S2, the overall heat transfer coefficient (U _coil ) of step S3 and the _total heat transfer amount (Q _total ) of step S4. Calculating a total heat transfer area A _coil of the heating coil required for replenishment and calculating a total length L _coil of the heating coil (S5); The total length L of the heating coil of step S5 and the total length L of the _preset heating coil of step S3 are compared by the central processing unit of the computer system, and the result is output when the lengths are the same. , If the length is not the same, and repeating the steps S3 to S5 until the length is the same and outputting the result (S6); Heating coil length calculation method in consideration of the vessel operating conditions consisting of. The method of claim 1; Of the data input to the computer system through the input device in the step S1 is the data required for the ship navigation, the temperature conditions of the operating area, the wind around the ship, the ship navigation speed, the basic information of the ship is injected into the ship heating coil A method of calculating the length of a heating coil in consideration of the ship operating conditions, characterized in that the heat source, the type of cargo loaded in the ship tank, the material and diameter constituting the heating coil, and the size of the tank according to the basic design.

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