CN-115859428-B - Pipe diameter calculation method and one-section structure of geothermal well heat exchange system

Abstract

The application relates to a pipe diameter calculation method and a one-section structure of a geothermal well heat exchange system, and relates to the field of geothermal well construction. The method comprises the steps of obtaining circulating water quantity and heat exchange quantity of a geothermal well based on heat exchange quantity requirements of users, determining the minimum pipe diameter of the inner diameter of a pumping pipe according to the relation between the circulating water quantity and the inner diameter and flow speed of the pumping pipe, the relation between the heat exchange quantity and the energy required by the total pressure drop of the pumping pipe along the path, and the relation between the heat exchange quantity and the energy required by the total pressure drop of the pumping pipe along the path, measuring the inner diameter of a heat exchange sleeve, and obtaining the maximum pipe diameter of the pumping pipe by combining the minimum wall thickness of the pumping pipe. Thereby determining the value range of the inner diameter of the water pumping pipe. The application can obtain the value range of the inner diameter of the water pumping pipe on the basis of the requirement of a user, thereby meeting the requirement of the geothermal well on heat supply quantity requirements of surrounding residents and the requirement of economy.

Inventors

• WANG ZHUOZHUO
• LIU ZHE
• WANG WEIYI
• GUO SHUAI
• DING HAIZHENG
• LIU XIAN
• YANG QIANTING
• MENG SHAN
• WEI XIAOYONG
• WANG YONGHONG
• JIANG JIAN
• WANG ZHI
• MA JINGCHEN
• HUANG YIBIN

Assignees

• 北京市工程地质研究所

Dates

Publication Date

20260512

Application Date

20221128

Claims (6)

1. 1. A pipe diameter calculation method of a geothermal well heat exchange system is characterized in that an open section (1) of the geothermal well heat exchange system comprises a coaxial sleeve (2) coaxially embedded in a heat exchange well, a water pumping pipe (3) for pumping geothermal water out of the geothermal well is arranged in the coaxial sleeve (2), the water pumping pipe (3) is vertically arranged in the heat exchange well, a submersible pump is arranged on the water pumping pipe (3), a plurality of water injection pipes (4) are vertically arranged in the coaxial sleeve (2), a separation disc (7) is arranged in the coaxial sleeve (2), a plurality of through holes (71) are formed in the separation disc (7), and the water injection pipes (4) and the water pumping pipes (3) are correspondingly penetrated and fixed in the through holes (71) one by one; the pipe diameter calculation method of the geothermal well heat exchange system comprises the following steps: Based on the heat exchange quantity requirement of a user, acquiring the circulating water quantity and heat exchange power of the geothermal well; Determining the minimum pipe diameter of the inner diameter of the water suction pipe according to the relation between the circulating water quantity and the inner diameter and the flow speed of the water suction pipe, the relation between the heat exchange power and the energy required by the total pressure drop of the water suction pipe along the path, and the relation between the heat exchange power P and the energy required by the total pressure drop of the water suction pipe along the path, wherein the relation specifically comprises that P is more than or equal to 4W; and measuring the inner diameter of the heat exchange sleeve, and acquiring the maximum pipe diameter of the water pumping pipe by combining the minimum wall thickness of the water pumping pipe, thereby determining the value range of the inner diameter of the water pumping pipe.
2. 2. The method for calculating the pipe diameter of the geothermal well heat exchange system according to claim 1, wherein the circulating water quantity Q w and the heat exchange power P of the geothermal well are obtained based on the heat exchange quantity requirement of a user; Q w =v o ·S o Wherein v o is the flow velocity of water in the water pumping pipe, S o is the effective flow area of the water pumping pipe, and S o =π(d o ÷2) 2 ,d o is the inner diameter of the water pumping pipe; Deep drop caused by pumping pipe resistance ; The energy required by the total pressure drop along the water pump pipeline is W=ρ.g.1.1.H.Q w /1000; Wherein the method comprises the steps of Is a resistance coefficient, and is obtained through table lookup or sampling detection; For geothermal water density, measured by sampling; for the gravitational acceleration of the work surface, The extension length of the pumping pipe in the geothermal well is determined according to the depth of the geothermal well; Selecting coaxial sleeve of pump chamber section according to inner diameter of geothermal well, and measuring inner diameter of coaxial sleeve of pump chamber section part of geothermal well And (2) and , The minimum value of the wall thickness of the pumping pipe is 6mm; And calculating the proper inner diameter range of the water pumping pipe according to the formula.
3. 3. The method for calculating pipe diameter of geothermal well heat exchange system according to claim 2, wherein the pipe diameter is calculated by using a calculation method of pipe diameter calculation method of geothermal well heat exchange system Wherein v i is the flow velocity of water in the water injection pipe, and the number of the water injection pipes is The inner diameter of the water injection pipe is The effective flow area of the water injection pipe is ; ; And said Wherein The minimum value of the wall thickness of the water injection pipe is 4mm; and calculating the pipe diameter range of the water injection pipe.
4. 4. The method for calculating pipe diameter of geothermal well heat exchange system according to claim 3, wherein the formula is defined by Calculating the value range of the number of the water injection pipes, wherein, Is a spacing coefficient, and 。
5. 5. The method for calculating pipe diameter of geothermal well heat exchange system according to claim 4, wherein the formula is given by Calculating the number of water injection pipes, wherein 。
6. 6. The method for calculating pipe diameter of geothermal well heat exchange system according to claim 5, wherein the pipe diameter is calculated by using a calculation method of pipe diameter calculation method of geothermal well heat exchange system 。

Description

Pipe diameter calculation method and one-section structure of geothermal well heat exchange system Technical Field The application relates to the field of geothermal well construction, in particular to a pipe diameter calculation method and an open section structure of a geothermal well heat exchange system. Background Geothermal energy use projects such as geothermal heating, geothermal power generation, geothermal agriculture, ground source heat pump and the like are not separated from corresponding geothermal development technologies, and most geothermal hot spring resources at present depend on manual excavation of geothermal wells to transfer geothermal resources deep underground to the ground and then heat exchange and heating are carried out. The coaxial sleeve heat exchange system is a device for underground heat energy exploitation and collection, and can be divided into a closed coaxial sleeve heat exchange system and an open coaxial sleeve heat exchange system according to principles. Compared with a closed coaxial sleeve heat exchange system, the open coaxial sleeve heat exchange system has higher heat exchange quantity and better heat exchange efficiency, thereby having great and profound research significance. However, in the construction process of the actual open type coaxial sleeve heat exchange system, the condition that heat is wasted due to excessive heat conversion or the heat consumption requirement of a user cannot be met due to insufficient heat conversion often occurs. In the open type coaxial double-pipe heat exchange system, the pipe diameters of the water suction pipe and the water injection pipe are selected as one of the main factors influencing the heat exchange efficiency of the open type coaxial double-pipe heat exchange system, so that the pipe diameter of the inner pipe in the open type coaxial double-pipe heat exchange system is reasonably calculated and selected according to actual conditions, and the utilization rate of geothermal energy is very necessary to be improved maximally. Disclosure of Invention In order to reduce the situation that heat waste is caused by excessive heat conversion of a heat exchange system or heat consumption requirements of users cannot be met due to insufficient heat conversion, the application provides a pipe diameter calculation method and an open section structure of a geothermal well heat exchange system. The application provides a pipe diameter calculation method and an open section structure of a geothermal well heat exchange system, comprising the following steps of obtaining circulating water quantity and heat exchange power of a geothermal well based on heat exchange quantity requirements of users; Determining the minimum pipe diameter of the inner diameter of the water suction pipe according to the relation between the circulating water quantity and the inner diameter and the flow speed of the water suction pipe, the energy required by the total pressure drop of the water suction pipe along the path, and the relation between the heat exchange power and the energy required by the total pressure drop of the water suction pipe along the path; And measuring the inner diameter of the heat exchange sleeve, and combining the minimum wall thickness of the water pumping pipe to obtain the maximum pipe diameter of the water pumping pipe. Thereby determining the value range of the inner diameter of the water pumping pipe. Through adopting above-mentioned technical scheme, can obtain the value range of drinking-water pipe internal diameter on the basis of user's demand to satisfy the geothermal well and supply heat demand and the requirement of economic nature to resident around, reduce heat transfer system conversion heat too much and cause the heat extravagant, perhaps the conversion heat is too little to lead to the condition that can't satisfy user's heat demand. Optionally, based on the heat exchange requirement of the user, acquiring the circulating water quantity Q w and the heat exchange power P of the geothermal well; Qw＝Vo·So Wherein V o is the flow velocity of water in the water pumping pipe, S o is the effective flow area of the water pumping pipe, and S o＝π((do÷2)2),do is the inner diameter of the water pumping pipe; deep drop caused by pumping pipe resistance The energy required by the total pressure drop of the water pump pipeline along the journey is W=ρ×g×1.1×H×Q w ×1000; Wherein lambda is a resistance coefficient, which can be obtained through table lookup, sampling detection can be obtained, rho is geothermal water density, which can be obtained through sampling measurement, g is the gravity acceleration of the operation ground surface, L is the extension length of a pumping pipe in a geothermal well, and can be determined according to the depth of the geothermal well; and P in unit time is more than or equal to 4R; Selecting an open section of coaxial sleeve according to the inner diameter of the geothermal well, measuring