A method for calculating the heat balance of aquaculture ponds

Abstract

This invention discloses a method for calculating the heat balance of aquaculture ponds, comprising the following steps: S1. Determining the heat exchange terms of the aquaculture pond; S2. Calculating the heat exchange terms of the aquaculture pond; S3. Calculating the instantaneous heat or cooling consumption of the aquaculture pond. If the instantaneous heat or cooling consumption does not need to be calculated, proceed directly to step 4; S4. Calculating the heat load or cooling load of the aquaculture pond. If the heat load or cooling load is known, proceed sequentially to steps 5 and 6, or proceed to steps 5 or 6 separately; S5. Calculating the thermal resistance of the enclosure structure of the aquaculture pond; S6. Calculating the indoor air design temperature of the aquaculture pond. The method provided by this invention can not only be used to evaluate the operating conditions and energy consumption levels of existing or planned aquaculture ponds; it also provides the technical parameters required for the configuration of heat and cold sources, structural design, and ventilation and air conditioning design of the workshop where the pond is located; and it can be applied not only to the aquaculture field but also to other civilian sites, agricultural sites, and industrial workshops.

Description

Technical Field

[0001] This invention belongs to the field of energy-saving and emission-reduction design and evaluation in aquaculture, specifically, it relates to a method for calculating the heat balance of aquaculture ponds. Background Technology

[0002] my country is a major producer, trader, and consumer of aquatic products, ranking first in the world in aquatic product output and being the only country in the world where aquaculture production exceeds fishing production. Factory aquaculture, with its advantages of centralized waste treatment, effective reduction of environmental pollution, suitability for large-scale farming, high degree of automation, and low operating costs, has become the development trend of the aquaculture industry in the 21st century. Past research and engineering efforts have focused primarily on system design, aquaculture equipment, water purification, and heat transfer.

[0003] Reference 1 (Wei Jingguang, Wu Siting, Qin Qiwei, Lei Xiaoxia, Zhan Zhouling, Xu Qiongyue, Cao Helong. An Aquaculture System [P]. Chinese Patent: CN202410752577.1, 2024-08-16) discloses an aquaculture system, including an aquaculture pond, a filtration device, a deaeration device, a biochemical pond, a return water device, and a sedimentation removal device. The aquaculture pond has an inlet system at its bottom and a drain outlet on its side wall. The filtration device is connected to the drain outlet via a pipe for filtering the aquaculture water flowing out of the drain outlet. The deaeration device is connected to the filtration device for removing carbon dioxide from the water discharged from the filtration device. The biochemical pond is used to remove heavy metal ions from the water discharged from the deaeration device. The return water device is connected to both the biochemical pond and the aquaculture pond for sending the water discharged from the biochemical pond back into the aquaculture pond. The sedimentation removal device is located inside the aquaculture pond and can move along the inner bottom surface of the pond, scooping up sediment at the bottom of the pond during its movement. This aquaculture system can clean the culture tanks, reduce sedimentation inside, and thus improve the quality of the culture water.

[0004] Reference 2 (Huang Yaorong. A recirculating aquaculture unit and aquaculture system [P]. Chinese Patent: CN202410575458.3, 2024-06-28) relates to the field of aquaculture technology, specifically to a recirculating aquaculture unit and aquaculture system, including a circular shell and a triangular trough. This invention, by incorporating a rotating cleaning component, a circular shell, a triangular trough, and a drain pipe, allows floating impurities to enter the circular shell through the triangular trough during use, thus treating the floating impurities. Driven by a second motor, the connecting plate and scraper rotate, and the cleaning brushes on the connecting plate and scraper clean the inner walls of the circular shell, circular shell, and movable shell. Floating impurities are discharged through the drain pipe, and settled impurities can be discharged by controlling the opening and closing of a second valve. This effectively reduces the adsorption of impurities inside the aquaculture unit, improves the cleaning effect of the aquaculture unit, and facilitates aquaculture use. This invention has the advantages of effectively improving the cleanliness and ease of use of aquaculture.

[0005] Reference 3 (Yan Jing, Zhao Sifan, Deng Deng. An aquaculture tank and aquaculture equipment [P]. Chinese Patent: CN202322984760.8, 2024-06-14) relates to an aquaculture tank and aquaculture equipment, including a container body, a water pump, and filter blocks. The container body includes a receiving tank for storing water. The upper outer wall of the container body is provided with a receiving block with a mounting slot, and the mounting slot is connected to the receiving tank. The number of filter blocks corresponds to the number of receiving blocks, and multiple filter blocks are installed in multiple mounting slots. The water pump is fixed at the lower end of the container body, and the water pump's pumping end passes through the container body and is connected to the receiving tank. The water pump's outlet end is connected to the receiving tank through the mounting slot. By observing the flow rate of the water after dilution and filtration through the filter block, it can be determined whether the filter block needs to be replaced. In the process of circulating water treatment, the filter block is usually built into the inside of the aquaculture equipment, allowing the filter block to be in direct contact with the water, which makes it inconvenient to replace it in time. This can lead to the accumulation of excessive impurities in the filter block, resulting in unclean water quality.

[0006] Reference 4 (Zheng Zhican. A device and method for purifying aquaculture using internal circulation [P]. Chinese Patent: CN202211105929.1, 2024-08-16) relates to the field of circulation purification technology, and more specifically to a device and method for purifying aquaculture using internal circulation, including a main body structure. The main body structure includes an aquaculture tank, the inner surface of which has a groove. The front of the top of the aquaculture tank has a tank opening cover, and the front of the tank opening cover has an opening handle fixedly connected to it. Both sides of the openable lid are fixedly connected with hinges. A baffle is provided in the middle of the top of the inner surface of the breeding box. A baffle fixing block is fixedly connected to the front of the baffle and the top of the back. A baffle fixing bolt is provided at the bottom of each of the six baffle fixing blocks. Side connecting plates are provided in the middle of both sides and the back of the breeding box. Side fixing bolts are provided at the top and bottom of the outer sides of the four side connecting plates. A circulation and purification structure is provided on the back of the openable lid of the box. The circulation and purification structure includes a circulation block. A groove is opened on one side of the back of the circulation block.

[0007] Reference 5 (Li Weidong, Yao Xingrui, Li Wenqing, Deng Jing, Yao Rongcai, Li Zhanzeng, Chang Wenan. A method for treating aquaculture wastewater and a comprehensive system for treating aquaculture wastewater [P]. Chinese Patent: CN201710927596.3, 2023-10-03) relates to a comprehensive system for treating aquaculture wastewater and a method for treating aquaculture wastewater using the above-mentioned device. The comprehensive system for treating aquaculture wastewater includes a collection tank, a bioreactor, an aeration regulating tank, and a coagulation sedimentation tank connected in sequence. The collection tank is equipped with a screen. The upper end of the bioreactor is equipped with an inlet, which is connected to the outlet of the collection tank. The coagulation sedimentation tank and the aeration regulating tank are respectively equipped with a stirrer. A horizontally arranged rotating shaft is installed in the bioreactor. Multiple support rods are fixedly installed on the rotating shaft. The support rods are arranged perpendicular to the rotating shaft. Spiral blades are fixedly installed at the free ends of the support rods. The outer surface of the blades is uneven and coated with a microbial degradation agent. The advantages of this invention are its high efficiency in degrading aquaculture pollution and its low cost.

[0008] Reference 6 (Wang Jiulong. Research on Optimization Design of Low-Energy Factory Fish Farming Pond [D]. Yinchuan: Yinchuan University, 2022) established a mathematical heat transfer model for factory fish farming ponds, determined the boundary conditions of the fish pond heat transfer model, and used the FLUENT software package in ANSYS simulation software to simulate the steady-state heat transfer process of the fish pond, obtaining a three-dimensional steady-state heat transfer temperature distribution cloud map of the fish pond. Experiments were designed to verify and compare the simulation results. The experimental results show that the established fish pond heat transfer model conforms to the actual fish pond heat transfer process. When carrying out the heat preservation optimization design of the fish pond, the relevant optimization results can be obtained by changing the relevant parameters of the heat transfer model.

[0009] In summary, past studies have paid little attention to the energy balance of aquaculture ponds, making it inconvenient to conduct energy-saving design and assessment for aquaculture ponds. Summary of the Invention

[0010] This invention provides a method for calculating the heat balance of aquaculture ponds, which is suitable for the analysis of operating conditions and energy-saving design of aquaculture ponds in various climate zones. It provides calculation methods for parameters such as the heat or cooling consumption of the pond, the load or cooling load, the thermal resistance of the enclosure structure, and the indoor air design temperature, so as to realize the heat balance calculation and energy-saving assessment of aquaculture ponds.

[0011] This invention is achieved through the following technical solution:

[0012] A method for calculating the heat balance of an aquaculture pond includes the following steps:

[0013] S1. Determine the heat exchange components of the aquaculture pond;

[0014] S2. Calculate the heat exchange term of the aquaculture pond;

[0015] S3. Calculate the instantaneous heat or cooling consumption of the aquaculture pond. If it is not necessary to calculate the instantaneous heat or cooling consumption, proceed directly to step 4.

[0016] S4. Calculate the heat load or cold load of the aquaculture pond. If the heat load or cold load is known, you can proceed to steps 5 and 6 sequentially, or you can proceed to steps 5 or 6 separately.

[0017] S5. Calculate the thermal resistance of the enclosure structure of the aquaculture pond;

[0018] S6. Calculate the indoor air design temperature of the aquaculture pond.

[0019] Preferably, the heat exchange component of the aquaculture pond in step S1 includes the following: heat exchange capacity of the pond wall. Q 1. Heat exchange at the bottom of the pool Q 2. Heat exchange at the pool opening Q 3. Hydration and Heat Exchange Q 4. Replenishing Qi and exchanging heat Q 5. Other heat exchange Q 6.

[0020] Preferably, the calculation method for each heat exchange term in step S2 includes the following:

[0021] (1) Heat exchange in the pool wall Q 1

[0022] Q 1= α 1 K 1 F1( t s - t k )

[0023] Q 1 — Heat exchanged through the pool wall, W;

[0024] α 1 — Temperature difference correction factor for the pool wall;

[0025] K 1 — Heat transfer coefficient of the pool wall, W / (m²) 2 ·℃);

[0026] F 1 — Area of ​​the pool wall, m 2 ;

[0027] t s —The temperature of the pool water, in °C;

[0028] t k —The temperature of the air outside the pool wall, in °C;

[0029] (2) Heat exchange at the bottom of the pool Q 2

[0030] Q 2= α 2 K 2 F 2( t s - t d )

[0031] Q 2 — Heat exchange at the bottom of the pool, W;

[0032] α 2 — Temperature difference correction factor at the bottom of the pool;

[0033] K 2 — Heat transfer coefficient at the bottom of the pool, W / (m²) 2 ·℃);

[0034] F 2 — Area of ​​the pool bottom, m 2 ;

[0035] t d —Temperature of the soil outside the pool bottom, °C;

[0036] (3) Heat exchange at the pool inlet Q 3

[0037] Heat exchange at pool openingQ 3. Including convection heat transfer at the pool inlet Q 31 Heat exchange with pool opening evaporation Q 32

[0038] Convection heat transfer at pool opening Q 31

[0039] Q 31 = α 31 K 31 F 3( t s - t k )

[0040] Q 31 —Heat exchanged via convection at the pool outlet, W;

[0041] α 31 —Temperature difference correction factor for convection heat transfer at the pool opening;

[0042] K 31 —Heat transfer coefficient of convective heat transfer at the pool opening, W / (m²) 2 ·℃);

[0043] F 3 — Area of ​​the pool opening, in meters 2 ;

[0044] Evaporation heat exchange at pool outlet Q 32

[0045] Q 32 = 0.28α 32 rF 3g

[0046] Q 32 —Evaporation heat transfer at the pool outlet, W;

[0047] α 32 —Correction factor for evaporative heat transfer at the pool outlet;

[0048] r —Heat of condensation of water vapor, kJ / kg;

[0049] g — the amount of water vapor evaporated per unit area, kg / (m²) 2·h);

[0050] F 3 — Area of ​​the pool opening, in meters 2 ;

[0051] (4) Water replenishment and heat exchange Q 4

[0052] Q 4= c s r s V 4( t s- t j )

[0053] Q 4 — Hydration and heat exchange, W;

[0054] c s —Specific heat of water replenishment, J / (kg·℃);

[0055] r s —Water density, kg / m³ 3 ;

[0056] V 4 — Volumetric flow rate of replenishment water, m 3 / s;

[0057] t j —Inlet water temperature for water replenishment, °C;

[0058] (5) Replenishing Qi and exchanging heat Q 5

[0059] Q 5= α 5 c q r q V 5( t s - t q )

[0060] Q 5 — Replenishing Qi and exchanging heat, W;

[0061] A 5 — Add the correction factor for the heat exchange;

[0062] c q—Specific heat of Qi replenishment, J / (kg·℃);

[0063] r q — Density of supplementary gas, kg / m³ 3 ;

[0064] V 5 — Volumetric flow rate of supplementary gas, m 3 / s;

[0065] t q —Intake temperature for supplemental air, °C;

[0066] (6) Other heat exchange Q 6

[0067] Other heat exchange values ​​are determined by the specific aquaculture process; heat loss is recorded as a positive value, and heat gain as a negative value.

[0068] Preferably, in step S3, the heat consumption of the aquaculture pond is calculated. Q R and cooling capacity Q L It includes the following:

[0069] Heat consumption

[0070] Q R = Q 1+ Q 2+ Q 3+ Q 4+ Q 5+ Q 6

[0071] If the sum of the above six items is positive, the calculation result is the heat consumption. Q R

[0072] If the sum of the above six items is negative, the calculation result is the cooling load. Q L

[0073] Q L =- Q R .

[0074] Preferably, in step S4, the heat load of the aquaculture pond is calculated. Q R ， or cooling load Q L ， It includes the following:

[0075] Heat load of aquaculture ponds Q R ， This refers to the heat consumption under the most unfavorable working conditions in winter, also known as the design heat consumption.

[0076] Cooling load of aquaculture ponds Q L ， This refers to the cooling load under the most unfavorable operating conditions in summer, also known as the design cooling load.

[0077] Preferably, the calculation of the thermal resistance of the enclosure structure of the aquaculture pond in step S5 includes the following:

[0078] Winter operating conditions:

[0079] (1) Design thermal resistance of the pool wall R 1 ’

[0080] R 1 ’ = 1 / K 1 ， = ( Q R ， -Q 2 ， -Q 3 ， -Q 4 ， -Q 5 ， -Q 6 ， ) / α 1 ， F 1 ， ( t s ， - t k ， )

[0081] R 1 ’ —Design thermal resistance of the pool wall, (m) 2 ·℃) / W;

[0082] K 1 ， —Design heat transfer coefficient of the pool wall, W / (m²) 2 ·℃);

[0083] Q 2 ， —The pool bottom is designed for heat exchange in W;

[0084] Q 3 ， —Designed heat exchange capacity of the pool opening, W;

[0085] Q 4 ， —The design for replenishing water generates heat in W;

[0086] Q 5 ， —The heat exchange capacity of the Qi-replenishing design is in W;

[0087] Q 6 ， —Other design heat exchange capacity, W;

[0088] α 1 ， —Design temperature difference correction coefficient for the pool wall;

[0089] F 1 ， —Design area of ​​the pool wall, m 2 ;

[0090] t s ， —Design temperature of the pool water, °C;

[0091] t k ， —Design air temperature outside the pool wall, °C;

[0092] (2) Design thermal resistance of the pool bottom R 2 ’

[0093] R 2 ’ = 1 / K 2 ， = ( Q R ， -Q 1 ， -Q 3 ， -Q 4 ， -Q 5 ， -Q 6 ， ) / α 2 ， F 2 ， ( t s， - t d ， )

[0094] R 2 ’ —Design thermal resistance of the pool bottom, (m) 2 ·℃) / W;

[0095] K 2 ， —Design heat transfer coefficient of the pool bottom, W / (m²) 2 ·℃);

[0096] Q 1 ， —The heat exchange capacity of the pool wall is designed in W;

[0097] A 2 ， —Design temperature difference correction coefficient for the pool bottom;

[0098] F 2 ， —Designed pool bottom area, m 2 ;

[0099] t s ， —Design temperature of the pool water, °C;

[0100] t d ， —Design soil temperature outside the pool bottom, °C.

[0101] Preferably, summer operating conditions:

[0102] During summer operation, calculating the design thermal resistance of the pond walls and bottom only requires considering the heat load of the aquaculture pond. Q R ， Change to cooling load Q L ， .

[0103] Preferably, the calculation of the indoor air design temperature of the aquaculture pond in step S6 includes the following:

[0104] Winter operating conditions:

[0105] Once the structural design, aquaculture process, and configuration of heat and cold sources for aquaculture ponds are fixed, the indoor air design temperature must satisfy the following equation:

[0106] Q 1 ， + Q3 ， = Q R ， -( Q 2 ， + Q 4 ， + Q 5 ， + Q 6 ， ).

[0107] Preferably, summer operating conditions:

[0108] During summer operation, to calculate the indoor air design temperature of aquaculture ponds, it is only necessary to consider the heat load of the aquaculture ponds. Q R ， Change to cooling load Q L ， .

[0109] Beneficial effects: The energy balance calculation method for aquaculture ponds provided by this invention can be used to assess the operating conditions and energy consumption levels of existing or planned aquaculture ponds; the heating and cooling load calculation method can provide a basis for the design and selection of heating and cooling sources for aquaculture farms; the thermal resistance calculation method for the building envelope can provide a basis for the design of the building envelope; and the indoor air temperature calculation method can provide a design basis for the ventilation and air conditioning system of aquaculture workshops. This invention can be used not only in the field of aquaculture but also in other agricultural and animal husbandry fields or industrial workshops. Attached Figure Description

[0110] Figure 1 This is a schematic diagram of the operation steps of the present invention. Detailed Implementation

[0111] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings: These embodiments are implemented based on the technical solution of the present invention, and provide detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to the following embodiments.

[0112] like Figure 1 As shown:

[0113] The dimensions of the tilapia fry rearing pond in a certain workshop are: 9m long, 8m wide, and 2m deep. The heat transfer coefficient of the pond wall is 0.96W / (m²). 2 The optimal water temperature in summer is 28℃, the highest indoor air temperature is 35℃, and the heat transfer coefficient at the bottom of the pool is 0.27W / (m²). 2 The temperature of the soil outside the pool bottom is 28℃, and the heat transfer coefficient of convective heat transfer at the pool opening is 3.47 W / (m²). 2The correction factor for evaporative heat transfer at the pool outlet is 0.25 (℃). The condensation heat of water at 28℃ is 2528 kJ / kg. At a room temperature of 35℃ and a relative humidity of 70%, the amount of water vapor evaporated per unit area is 0.24 kg / (m²). 2 The average water replenishment flow rate is 0.1 m³ / h. 3 / h, specific heat of makeup water 4200J / (kg·℃), density 1000kg / m³ 3 The maximum water supply temperature is 35℃, and the average air supply flow rate is 116.0847 m³ / h. 3 / h, the highest temperature is 35℃, the specific heat of air at 35℃ is 1005 J / (kg·℃), and the density is 1.144 kg / m³. 3 .

[0114] S1. Determine the heat exchange components of the aquaculture pond;

[0115] The heat exchange components of the tilapia fry rearing ponds include the following: heat exchange capacity of the pond walls. Q 1. Heat exchange at the bottom of the pool Q 2. Heat exchange at the pool opening Q 3. Hydration and Heat Exchange Q 4. Replenishing Qi and exchanging heat Q 5;

[0116] S2. Calculate the heat exchange term of the aquaculture pond;

[0117] No calculations are needed; proceed directly to step 4.

[0118] S3. Calculate the instantaneous heat or cooling consumption of the aquaculture pond. If it is not necessary to calculate the instantaneous heat or cooling consumption, proceed directly to step 4.

[0119] No calculations are needed; proceed directly to step 4.

[0120] S4. Calculate the heat load or cold load of the aquaculture pond. If the heat load or cold load is known, you can proceed to steps 5 and 6 sequentially, or you can proceed to steps 5 or 6 separately.

[0121] (1) Pool wall design for heat exchange Q 1 ，

[0122] Q 1 ， = α 1 K 1 F 1( t s - t k )=1.0×0.96×[(9+8)×2×2]×(28-35)=-456.96W

[0123] Q 1 — Heat exchanged through the pool wall, W;

[0124] α 1 — Temperature difference correction factor for the pool wall;

[0125] K 1 — Heat transfer coefficient of the pool wall, W / (m²) 2 ·℃);

[0126] F 1 — Area of ​​the pool wall, m 2 ;

[0127] t s —The temperature of the pool water, in °C;

[0128] t k —The temperature of the air outside the pool wall, in °C;

[0129] (2) Heat exchange design at the bottom of the pool Q 2 ，

[0130] Q 2 ， = α 2 K 2 F 2( t s - t d )=1.0×0.27×(9×8)×(28-28)=0W

[0131] Q 2 — Heat exchange at the bottom of the pool, W;

[0132] α 2 — Temperature difference correction factor at the bottom of the pool;

[0133] K 2 — Heat transfer coefficient at the bottom of the pool, W / (m²) 2 ·℃);

[0134] F 2 — Area of ​​the pool bottom, m 2 ;

[0135] t d —Temperature of the soil outside the pool bottom, °C;

[0136] (3) Heat exchange design at the pool opening Q 3 ，

[0137] Pool opening design for heat exchange Q 3， Including pool outlet design for convective heat transfer Q 31 ， The design of the pool opening facilitates evaporation and heat exchange. Q 32 ，

[0138] Pool opening design for convective heat transfer Q 31 ，

[0139] Q 31 ， = α 31 K 31 F 3( t s - t k )=1.0×3.47×(9×8)×(28-35)=-1748.88W

[0140] Q 31 —Heat exchanged via convection at the pool outlet, W;

[0141] α 31 —Temperature difference correction factor for convection heat transfer at the pool opening;

[0142] K 31 —Heat transfer coefficient of convective heat transfer at the pool opening, W / (m²) 2 ·℃);

[0143] F 3 — Area of ​​the pool opening, in meters 2 ;

[0144] Pool opening design for evaporative heat exchange Q 32 ，

[0145] Q 32 ， = 0.28α 32 rF 3g=0.28×0.25×2528×(8×9)×0.24=3057.88W

[0146] α 32 —Correction factor for evaporative heat transfer at the pool outlet;

[0147] Q 32 —Evaporation heat transfer at the pool outlet, W;

[0148] r —Heat of condensation of water vapor, kJ / kg;

[0149] g — the amount of water vapor evaporated per unit area, kg / (m²) 2 ·h);

[0150] F 3 — Area of ​​the pool opening, in meters 2 ;

[0151] Q 3 ， = Q 31 ， + Q 32 ， =-1748.88+3057.88=1039W

[0152] (4) Water replenishment design for heat exchange Q 4 ，

[0153] Q 4 ， = c s r s V 4( t s- t j )=4200×1000×(0.1÷3600)×(28-35)=-816.67W

[0154] Q 4 — Hydration and heat exchange, W;

[0155] c s —Specific heat of water replenishment, J / (kg·℃);

[0156] r s —Water density, kg / m³ 3 ;

[0157] V 4 — Volumetric flow rate of replenishment water, m 3 / s;

[0158] t j —Inlet water temperature for water replenishment, °C;

[0159] (5) Gas replenishment design for heat exchange Q 5 ，

[0160] Q 5 ， = α 5 c q r q V 5( t s - t q )

[0161] =1.0×1005×1.144×(116.0847÷3600)×(28-35)=-259.52W

[0162] Q 5 — Replenishing Qi and exchanging heat, W;

[0163] A 5 — Add the correction factor for the heat exchange;

[0164] c q —Specific heat of Qi replenishment, J / (kg·℃);

[0165] r q — Density of supplementary gas, kg / m³ 3 ;

[0166] V 5 — Volumetric flow rate of supplementary gas, m 3 / s;

[0167] t q —Intake temperature for supplemental air, °C;

[0168] Cooling load of aquaculture ponds Q L ， This refers to the cooling load under the most unfavorable operating conditions in summer, also known as the design cooling load.

[0169] Q L ， =- Q L ， =-( Q 1 ， + Q 2 ， + Q 3 ， + Q4 ， + Q 5 ， )

[0170] =-(-456.96W+0+1039-816.67-259.52)=224.15W

[0171] The dimensions of the breeding pond in a certain seedling workshop are: 5m long, 3m wide, and 1.5m deep. The optimal water temperature in winter is 28℃, the minimum indoor air temperature is 5℃, the designed heat exchange at the bottom of the pond is 517W, the designed heat exchange at the mouth of the pond is 2008W, the designed heat exchange for water replenishment is 968W, the designed heat exchange for air replenishment is 527W, and the designed heat consumption of the breeding pond is 5000W.

[0172] S1. Determine the heat exchange components of the aquaculture pond;

[0173] The heat exchange components of an aquaculture pond include the following: heat exchange capacity of the pond walls. Q 1. Heat exchange at the bottom of the pool Q 2. Heat exchange at the pool opening Q 3. Hydration and Heat Exchange Q 4. Replenishing Qi and exchanging heat Q 5;

[0174] S2. Calculate the heat exchange term of the aquaculture pond;

[0175] No calculations are needed; proceed directly to step 4.

[0176] S3. Calculate the instantaneous heat or cooling consumption of the aquaculture pond. If it is not necessary to calculate the instantaneous heat or cooling consumption, proceed directly to step 4.

[0177] No calculations are needed; proceed directly to step 4.

[0178] S4. Calculate the heat load or cold load of the aquaculture pond. If the heat load or cold load is known, you can proceed to steps 5 and 6 sequentially, or you can proceed to steps 5 or 6 separately.

[0179] Heat consumption design of aquaculture ponds Q R ， =5000W;

[0180] The pool bottom is designed for heat exchange. Q 2 ， =517W;

[0181] The design of the pool opening facilitates heat exchange. Q 3 ， =2008W;

[0182] Hydration design for heat exchange Q 4 ， =968W;

[0183] The design of replenishing Qi allows for heat exchange. Q 5 ， =527W;

[0184] S5. Calculate the thermal resistance of the enclosure structure of the aquaculture pond;

[0185] Winter operating conditions:

[0186] (1) Design thermal resistance of the pool wall R 1 ’

[0187] R 1 ’ = 1 / K 1 ， = ( Q R ， -Q 2 ， -Q 3 ， -Q 4 ， -Q 5 ， -Q 6 ， ) / α 1 ， F 1 ， ( t s ， - t k ， )

[0188] =(5000-517-2008-968-527) / 1.0×[(5+3)×2×1.5]×(28-5)

[0189] =980 / 552

[0190] =1.78(m 2 ·℃) / W.

[0191] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for calculating the heat balance of an aquaculture pond, characterized in that, Includes the following steps: S1. Determine the heat exchange parameters of the aquaculture pond, wherein the heat exchange parameters include the heat exchange capacity of the pond wall. Q 1. Heat exchange at the bottom of the pool Q 2. Heat exchange at the pool opening Q 3. Hydration and Heat Exchange Q 4. Replenishing Qi and exchanging heat Q 5. Other heat exchange Q 6. Other heat exchange Q 6. This is determined by the specific breeding process; heat loss is taken as a positive value, and heat gain is taken as a negative value. S2. Calculate the heat exchange term of the aquaculture pond; S3. Calculate the instantaneous heat or cooling demand of the aquaculture pond, specifically including the following steps: Calorie consumption: Q R = Q 1+ Q 2+ Q 3+ Q 4+ Q 5+ Q 6 If the sum of the above six items is positive, the calculation result is the heat consumption. Q R If the sum of the above six items is negative, the calculation result is the cooling load. Q L Q L =- Q R ， If you do not need to calculate instantaneous heat or cooling consumption, proceed directly to step 4; S4. Calculate the heat load or cooling load of the aquaculture pond, specifically including the following steps: Heat load of aquaculture ponds Q R ， This refers to the heat loss under the most unfavorable operating conditions in winter, also known as the design heat loss. Cooling load of aquaculture ponds Q L ， This refers to the cooling load under the most unfavorable operating conditions in summer, also known as the design cooling load. If the heat load or cooling load is known, you can proceed to steps 5 and 6 sequentially, or you can proceed to steps 5 or 6 separately. S5. Calculate the thermal resistance of the enclosure structure of the aquaculture pond; S6. Calculate the indoor air design temperature of the aquaculture pond.

2. The method for calculating the heat balance of an aquaculture pond according to claim 1, characterized in that, Step S2, which calculates the heat exchange term of the aquaculture pond, includes the following steps: (1) Heat exchange in the pool wall Q 1 Q 1= α 1 K 1 F 1( t s - t k ) Q 1 — Heat exchanged through the pool wall, W; α 1 — Temperature difference correction factor for the pool wall; K 1 — Heat transfer coefficient of the pool wall, W / (m²) 2 ·℃); F 1 — Area of ​​the pool wall, m 2 ; t s —The temperature of the pool water, in °C; t k —The temperature of the air outside the pool wall, in °C; (2) Heat exchange at the bottom of the pool Q 2 Q 2= α 2 K 2 F 2( t s - t d ) Q 2 — Heat exchange at the bottom of the pool, W; α 2 — Temperature difference correction factor at the bottom of the pool; K 2 — Heat transfer coefficient at the bottom of the pool, W / (m²) 2 ·℃); F 2 — Area of ​​the pool bottom, m 2 ; t d —Temperature of the soil outside the pool bottom, °C; (3) Heat exchange at the pool inlet Q 3 Heat exchange at pool opening Q 3. Including convection heat transfer at the pool inlet Q 31 Heat exchange with pool opening evaporation Q 32 Convection heat transfer at pool opening Q 31 Q 31 = α 31 K 31 F 3( t s - t k ) Q 31 —Convective heat transfer at the pool outlet, W; α 31 —Temperature difference correction factor for convection heat transfer at the pool opening; K 31 —Heat transfer coefficient of convective heat transfer at the pool opening, W / (m²) 2 ·℃); F 3 — Area of ​​the pool opening, in meters 2 ; Evaporation heat exchange at pool outlet Q 32 Q 32 = 0.28α 32 rF 3g Q 32 —Evaporation heat transfer at the pool outlet, W; α 32 —Correction factor for evaporative heat transfer at the pool outlet; r —Heat of condensation of water vapor, kJ / kg; g — the amount of water vapor evaporated per unit area, kg / (m²) 2 ·h); F 3 — Area of ​​the pool opening, in meters 2 ; (4) Water replenishment and heat exchange Q 4 Q 4= c s ρ s V 4( t s- t j ) Q 4 — Hydration and heat exchange, W; c s —Specific heat of water replenishment, J / (kg·℃); ρ s —Water density, kg / m³ 3 ; V 4 — Volumetric flow rate of replenishment water, m 3 / s; t j —Inlet water temperature for water replenishment, °C; (5) Replenishing Qi and exchanging heat Q 5 Q 5= α 5 c q ρ q V 5( t s - t q ) Q 5 — Replenishing Qi and exchanging heat, W; α 5 — Add the correction factor for the heat exchange; c q —Specific heat of Qi replenishment, J / (kg·℃); ρ q — Density of supplementary gas, kg / m³ 3 ; V 5 — Volumetric flow rate of supplementary gas, m 3 / s; t q —Intake temperature for supplemental air, °C.

3. The method for calculating the heat balance of an aquaculture pond according to claim 1, characterized in that, Step S5, which calculates the thermal resistance of the enclosure structure of the aquaculture pond, includes the following steps: Winter operating conditions: (1) Design thermal resistance of the pool wall R 1 ’ R 1 ’ = 1 / K 1 ， = ( Q R ， -Q 2 ， -Q 3 ， -Q 4 ， -Q 5 ， -Q 6 ， ) / α 1 ， F 1 ， ( t s ， - t k ， ) R 1 ’ —Design thermal resistance of the pool wall, (m) 2 ·℃) / W; K 1 ， —Design heat transfer coefficient of the pool wall, W / (m²) 2 ·℃); Q 2 ， —The pool bottom is designed for heat exchange in W; Q 3 ， —Designed heat exchange capacity of the pool opening, W; Q 4 ， —The design for replenishing water generates heat in W; Q 5 ， —The heat exchange capacity of the Qi-replenishing design is in W; Q 6 ， —Other design heat exchange capacity, W; α 1 ， —Design temperature difference correction coefficient for the pool wall; F 1 ， —Design area of ​​the pool wall, m 2 ; t s ， —Design temperature of the pool water, °C; t k ， —Design air temperature outside the pool wall, °C; (2) Design thermal resistance of the pool bottom R 2 ’ R 2 ’ = 1 / K 2 ， = ( Q R ， -Q 1 ， -Q 3 ， -Q 4 ， -Q 5 ， -Q 6 ， ) / α 2 ， F 2 ， ( t s ， - t d ， ) R 2 ’ —Design thermal resistance of the pool bottom, (m) 2 ·℃) / W; K 2 ， —Design heat transfer coefficient of the pool bottom, W / (m²) 2 ·℃); Q 1 ， —The heat exchange capacity of the pool wall is designed in W; α 2 ， —Design temperature difference correction coefficient for the pool bottom; F 2 ， —Designed pool bottom area, m 2 ; t s ， —Design temperature of the pool water, °C; t d ， —Design soil temperature outside the pool bottom, °C.

4. The method for calculating the heat balance of an aquaculture pond according to claim 3, characterized in that, Step S5, which calculates the thermal resistance of the enclosure structure of the aquaculture pond, includes the following steps: Summer operating conditions: During summer operation, calculating the design thermal resistance of the pond walls and bottom only requires considering the heat load of the aquaculture pond. Q R ， Change to cooling load Q L ， .

5. The method for calculating the heat balance of an aquaculture pond according to claim 3, characterized in that, Step S6, which calculates the indoor air design temperature for the aquaculture pond, includes the following steps: Winter operating conditions: Once the structural design, aquaculture process, and configuration of heat and cold sources for aquaculture ponds are fixed, the indoor air design temperature must satisfy the following equation: Q 1 ， + Q 3 ， = Q R ， -( Q 2 ， + Q 4 ， + Q 5 ， + Q 6 ， )。 6. The method for calculating the heat balance of an aquaculture pond according to claim 3, characterized in that, Step S6, which calculates the indoor air design temperature for the aquaculture pond, includes the following steps: Summer operating conditions: During summer operation, to calculate the indoor air design temperature of aquaculture ponds, it is only necessary to consider the heat load of the aquaculture ponds. Q R ， Change to cooling load Q L ， .

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