CN113239474B - Design method of pipe-sleeve heat exchanger for composite refrigerator in extremely-low temperature region - Google Patents
Design method of pipe-sleeve heat exchanger for composite refrigerator in extremely-low temperature region Download PDFInfo
- Publication number
- CN113239474B CN113239474B CN202110265626.5A CN202110265626A CN113239474B CN 113239474 B CN113239474 B CN 113239474B CN 202110265626 A CN202110265626 A CN 202110265626A CN 113239474 B CN113239474 B CN 113239474B
- Authority
- CN
- China
- Prior art keywords
- pipe
- heat exchanger
- low temperature
- tube
- temperature region
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/10—Geometric CAD
- G06F30/17—Mechanical parametric or variational design
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B39/00—Evaporators; Condensers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D7/00—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
- F28D7/10—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being arranged one within the other, e.g. concentrically
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
- G06F30/28—Design optimisation, verification or simulation using fluid dynamics, e.g. using Navier-Stokes equations or computational fluid dynamics [CFD]
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2500/00—Problems to be solved
- F25B2500/19—Calculation of parameters
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2113/00—Details relating to the application field
- G06F2113/08—Fluids
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
- G06F2119/08—Thermal analysis or thermal optimisation
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
- G06F2119/14—Force analysis or force optimisation, e.g. static or dynamic forces
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- General Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Geometry (AREA)
- Computer Hardware Design (AREA)
- Mechanical Engineering (AREA)
- Thermal Sciences (AREA)
- Mathematical Analysis (AREA)
- Mathematical Optimization (AREA)
- Evolutionary Computation (AREA)
- Pure & Applied Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mathematical Physics (AREA)
- Computing Systems (AREA)
- Algebra (AREA)
- Computational Mathematics (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
The invention discloses a design method of a pipe-in-pipe heat exchanger for a composite refrigerator in an extremely low temperature region, which can accurately design and calculate the pipe-in-pipe heat exchanger for the composite refrigerator in the extremely low temperature region, divide the pipe-in-pipe heat exchanger into small temperature difference heat exchange units, reduce the calculation errors of fluid physical property parameters and heat exchange wall surface heat conductivity coefficients caused by temperature changes, optimize the structural parameters of the pipe-in-pipe heat exchanger, comprehensively consider the heat exchange and flow characteristic factors of low-mass flow fluid in the pipe-in-pipe heat exchanger, and realize the performance optimization of the pipe-in-pipe heat exchanger under certain conditions. The method has important guiding significance and engineering application value for the design calculation and optimization of the tube-in-tube heat exchanger for the composite refrigerator in the extremely low temperature region, greatly improves the performance and efficiency of the composite refrigerator in the extremely low temperature region, and has very positive significance for the practicability of the tube-in-tube heat exchanger for the composite refrigerator in the extremely low temperature region, the aerospace application and the like.
Description
Technical Field
The invention belongs to the field of refrigeration and low-temperature engineering, particularly relates to a technology of a composite refrigerator in an extremely low temperature region, and particularly relates to a design method of a pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region.
Background
The ultra-low temperature zone composite refrigerator technology is an important means for extending the refrigerating temperature of a low-temperature refrigerator to 1-4K, combines the advantages of stability, high efficiency and reliability of a regenerative refrigerator and a Joule-Thompson refrigerator in different temperature zones, and becomes an important support for a plurality of advanced detection technologies and detection means.
The tube-in-tube heat exchanger for the compound refrigerator in the ultra-low temperature region is used as a core component of the compound refrigerator in the ultra-low temperature region, and the heat transfer performance and the flow resistance characteristic of the tube-in-tube heat exchanger directly influence the performance of the whole compound refrigerator in the ultra-low temperature region. Compared with the traditional pipe-in-pipe heat exchanger, the pipe-in-pipe heat exchanger for the compound refrigerator in the extremely low temperature region has the characteristics of large heat transfer temperature difference, small fluid channel, low fluid mass flow and the like, the pipe-in-pipe heat exchange for the compound refrigerator in the extremely low temperature region is used as a part with the maximum occupied space volume and mass of the Joule-Thompson cycle of the compound refrigerator, and in order to better realize space application, the space volume and the weight of the pipe-in-pipe heat exchange for the compound refrigerator in the extremely low temperature region are reduced as much as possible under the condition of meeting sufficient heat exchange conditions.
The pipe-in-pipe heat exchanger is a key part in the compound refrigerator in the extremely low temperature area. Ideally, it performs three main functions:
1) realizing high-efficiency heat exchange. The pipe sleeve heat exchanger is a key component of a composite refrigerator in an extremely low temperature region spanning from a 300K temperature region to a 4K temperature region or even a 1K temperature region, and because the precooling amount of a pre-stage precooling refrigerator is small, the realization of high-efficiency heat exchange between high-pressure fluid and low-pressure fluid is particularly important. Therefore, the tube-in-tube heat exchanger for the composite refrigerator in the extremely low temperature region is required to be of a geometric structure capable of realizing a large heat exchange area under a limited volume.
2) The pressure drop loss of the low-pressure side fluid is reduced as much as possible. The lowest refrigerating temperature of the compound refrigerating machine in the extremely low temperature region depends on the low pressure after throttling, and the fluid pressure drop of the low pressure side of the pipe-sleeve heat exchanger for the compound refrigerating machine in the extremely low temperature region is reduced as much as possible under the condition that the suction pressure of the compressor is fixed. Therefore, under the condition of meeting the requirement of sufficient heat exchange area, the lower flow resistance pressure drop of the low-pressure side of the tube-in-tube heat exchanger for the compound refrigerator in the extremely low temperature region is realized, and the heat exchanger is of great importance to the performance of the compound refrigerator.
3) Under the condition of meeting the heat exchange quantity and the flow resistance pressure drop, the volume and the weight of the pipe-in-pipe heat exchanger for the composite refrigerator in the extremely low temperature region are reduced as much as possible, and the method has important significance for realizing space application of the composite refrigerator in the extremely low temperature region.
Disclosure of Invention
In view of the defects of the existing research and technology, the invention provides a design method of a tube-in-tube heat exchanger for a composite refrigerator in an extremely low temperature region, which is characterized by comprising the following steps:
the method comprises the following steps: the design of the pipe-in-pipe heat exchanger for the compound refrigerator in the extremely low temperature region is carried out by taking the operating condition and the structural parameters of the pipe-in-pipe heat exchanger for the compound refrigerator in the extremely low temperature region and the physical property parameters of the fluid as design input parameters.
Step two: performing segmented calculation according to the operation condition of the pipe-in-pipe heat exchanger for the composite refrigerator in the ultra-low temperature region, and respectively calculating the enthalpy difference and the average logarithmic temperature difference of the inlet and the outlet of the pipe-in-pipe heat exchanger; and calculating the total heat transfer coefficient of the heat exchanger according to the structural parameters of the tube-in-tube heat exchanger for the composite refrigerator in the extremely low temperature region and the physical property parameters of the fluid.
Step three: and calculating the area of the pipe-in-pipe heat exchanger according to the enthalpy difference, the average logarithmic temperature difference and the total heat transfer coefficient of the inlet and the outlet of the pipe-in-pipe heat exchanger obtained by sectional calculation, and checking.
Step four: and calculating the total pressure drop of the pipe-in-pipe heat exchanger according to the calculated area of the pipe-in-pipe heat exchanger, the operating condition of the pipe-in-pipe heat exchanger and the fluid physical property parameters, and checking.
The second step specifically comprises the following steps:
1) dividing the pipe-in-pipe heat exchanger into a plurality of sections according to the operation condition of the pipe-in-pipe heat exchanger for the compound refrigerator in the ultra-low temperature region, and calculating the heat exchange quantity and the average logarithmic temperature difference of the heat exchanger according to the inlet and outlet parameters of the pipe-in-pipe heat exchanger and an enthalpy difference method;
2) according to fluid physical parameters and structural parameters in the tube-in-tube heat exchanger for the ultra-low temperature zone composite refrigerator; calculating the convection heat transfer coefficient of high-pressure side fluid in the pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region; calculating the convection heat transfer coefficient of the low-pressure side fluid in the pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region; calculating the heat conductivity coefficient of the heat exchange wall surface between high-pressure fluid and low-pressure fluid of the pipe-sleeve heat exchanger for the extremely low temperature region composite refrigerator at the base temperature;
3) and calculating the total heat transfer coefficient of each heat transfer unit of the pipe-in-pipe heat exchanger according to the total heat transfer coefficient calculation method of the dividing wall type heat exchanger.
The third step specifically comprises:
and calculating the heat exchange area of each heat transfer unit of the tube-in-tube heat exchanger according to an average logarithmic temperature difference method, checking the area of the heat exchanger according to the difference of the tube-in-tube heat exchange areas obtained by two successive iterative calculations, if the heat exchange requirements are met, performing the fourth step, and if the heat exchange requirements are not met, continuing to perform iterative calculation until the heat exchange area check meets the requirements.
The fourth step comprises the specific process that:
1) determining the actual heat exchange area of the pipe-in-pipe heat exchanger according to the step three, and calculating the fluid pressure drop of the low-pressure side of the pipe-in-pipe heat exchanger through a pressure drop calculation formula of the pipe-in-pipe heat exchanger;
2) checking resistance pressure drop according to the design requirement of low-pressure side pressure drop of the tube-in-tube heat exchanger for the extremely low temperature area composite refrigerator, and if the resistance pressure drop requirement is met, finishing the calculation; and if the pressure drop design requirement is not met, changing the structural parameters of the tube-in-tube heat exchanger for the composite refrigerator in the ultra-low temperature area, and repeating the second step and the third step to continue calculating until the pressure drop of the low-pressure side of the tube-in-tube heat exchanger for the composite refrigerator in the ultra-low temperature area meets the requirement.
The invention aims to divide a pipe-in-pipe heat exchanger into small temperature difference heat exchange units by adopting a design method of the pipe-in-pipe heat exchanger for the composite refrigerator in the extremely low temperature region, reduce calculation errors of physical property parameters of fluid and heat conductivity coefficient of a heat exchange wall surface caused by temperature change, accurately design and calculate the pipe-in-pipe heat exchanger for the composite refrigerator in the extremely low temperature region, optimize structural parameters of the pipe-in-pipe heat exchanger, comprehensively consider heat exchange and flow characteristic factors of low-mass flow fluid in the pipe-in-pipe heat exchanger, and realize performance optimization of the pipe-in-pipe heat exchanger under certain conditions.
Compared with the existing design method, the method has the following advantages:
(1) in the existing design method, the design method of the tube-in-tube heat exchanger for the composite refrigerator in the extremely low temperature region adopts a conventional heat exchanger design method, and the average temperature of the cold and hot ends of the heat exchanger is used as a reference temperature to calculate the physical property parameters of the fluid and the heat conductivity coefficient of the wall surface, so that the great deviation between the designed heat exchange effect and the actual heat exchange effect of the tube-in-tube heat exchanger for the composite refrigerator in the extremely low temperature region is caused. However, the design adopts a sectional calculation method, the tube-in-tube heat exchanger for the compound refrigerator in the extremely low temperature area is divided into a plurality of sections of heat exchange units, design calculation is carried out, the temperature of the cold end and the hot end of each heat exchange unit is used as a reference temperature, the design calculation of the tube-in-tube heat exchanger for the compound refrigerator in the extremely low temperature area is carried out, the error caused by the design calculation of the heat exchanger is greatly reduced, the design heat exchange effect of the tube-in-tube heat exchanger for the compound refrigerator in the extremely low temperature area is closer to the actual heat exchange effect, and the calculated value is more accurate.
(2) In the existing design method, the heat exchange performance of the heat exchanger is usually only considered for the design of the tube-in-tube heat exchanger for the compound refrigerator in the extremely low temperature region, but the resistance pressure drop problem caused by the fluid flowing through the heat exchanger is neglected, and the problem of the resistance pressure drop on the low pressure side of the tube-in-tube heat exchanger for the compound refrigerator in the extremely low temperature region is particularly critical to the performance of the compound refrigerator in the extremely low temperature region. Therefore, the design of the invention reduces the resistance pressure drop of the low-pressure side of the pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region as much as possible under the condition that the heat exchange area of the pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region is sufficient, and avoids the negative influence on the performance of the composite refrigerator in the extremely low temperature region caused by the overlarge resistance pressure drop of the low-pressure side of the pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region.
(3) The pipe-in-pipe heat exchanger for the ultra-low temperature area composite refrigerator designed by the method is applied to a pre-stage precooling heat exchange system of the ultra-low temperature area composite refrigerator, and has the following advantages compared with the pipe-in-pipe heat exchanger designed by the prior art; the pressure drop resistance of the low-pressure side of the pipe-sleeve heat exchanger for the compound refrigerating machine in the extremely low temperature region is reduced as much as possible under the condition of meeting the heat exchange area, and the total volume and the mass of the pipe-sleeve heat exchanger for the compound refrigerating machine in the extremely low temperature region are reduced as much as possible, so that the load of the precooler of the compound refrigerating machine in the extremely low temperature region is reduced, the structure of the whole compound refrigerating machine system is simplified, the structure is more compact, the reliability of the system is improved, the total mass of the compound refrigerating machine is reduced, and the space application requirement of the compound refrigerating machine in the extremely low temperature region is easier to meet.
Detailed Description
The invention relates to a design method and a process for a pipe-sleeve heat exchanger for a composite refrigerator in an extremely low temperature region, which comprises the following steps:
the method comprises the following steps: the design of the pipe-in-pipe heat exchanger for the compound refrigerator in the extremely low temperature region is carried out by taking the operating condition and the structural parameters of the pipe-in-pipe heat exchanger for the compound refrigerator in the extremely low temperature region and the physical property parameters of the fluid as design input parameters. General design input parameters include the high pressure fluid inlet temperature T of the tube-in-tube heat exchanger1Low pressure fluid inlet temperature T of tube heat exchanger2The design efficiency of the heat exchanger (generally 95-97 percent), the heat exchange wall surface material (generally stainless steel), the heat exchange fluid as helium working medium, and the inner diameter r of the inner pipe of the pipe-in-pipe heat exchanger1Inner pipe outer diameter r of pipe-in-pipe heat exchanger2Inner diameter r of outer pipe of pipe-in-pipe heat exchanger3And winding the pipe sleeve into a spiral pipe large-diameter R.
Step two: performing segmented calculation according to the operation condition of the pipe-in-pipe heat exchanger for the composite refrigerator in the ultra-low temperature region, and respectively calculating the enthalpy difference and the average logarithmic temperature difference of the inlet and the outlet of the pipe-in-pipe heat exchanger; and calculating the total heat transfer coefficient of the heat exchanger according to the structural parameters of the tube-in-tube heat exchanger for the composite refrigerator in the extremely low temperature region and the physical property parameters of the fluid. Because the temperature difference of the cold end and the hot end of the pipe-in-pipe heat exchanger for the composite refrigerator in the ultra-low temperature area is large, the heat exchange quantity is calculated by utilizing the enthalpy difference of the inlet and the outlet of the pipe-in-pipe heat exchanger.
Step three: and calculating the area of the pipe-in-pipe heat exchanger according to the enthalpy difference, the average logarithmic temperature difference and the total heat transfer coefficient of the inlet and the outlet of the pipe-in-pipe heat exchanger obtained by sectional calculation, and checking. The formula for calculating the heat exchange area of the pipe sleeve is
Here, A is the heat exchange area, Δ h is the inlet-outlet enthalpy difference of the heat exchanger, k is the total heat exchange coefficient, the area check is that the difference value of two iterative calculations before and after the area check does not exceed a certain value, and for the heat exchange tube with the diameter of 3mm, the value is generally set to be 1m2。
Step four: and calculating the total pressure drop of the pipe-in-pipe heat exchanger according to the calculated area of the pipe-in-pipe heat exchanger, the operating condition of the pipe-in-pipe heat exchanger and the fluid physical property parameters, and checking. When pressure drop checking is carried out, the total pressure drop on the low-pressure side is generally required to be not more than 3kPa for a compound refrigerator system in an extremely low temperature area.
2. The design method of the tube-in-tube heat exchanger for the very low temperature zone composite refrigerator according to claim 1, wherein the second step specifically comprises the following steps:
1) dividing the pipe-in-pipe heat exchanger into a plurality of sections according to the operation condition of the pipe-in-pipe heat exchanger for the compound refrigerator in the ultra-low temperature region, and calculating the heat exchange quantity and the average logarithmic temperature difference of the heat exchanger according to the inlet and outlet parameters of the pipe-in-pipe heat exchanger and an enthalpy difference method;
2) according to fluid physical parameters and structural parameters in the tube-in-tube heat exchanger for the ultra-low temperature zone composite refrigerator; calculating the convection heat transfer coefficient of high-pressure side fluid in the pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region; calculating the convection heat transfer coefficient of the low-pressure side fluid in the pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region; calculating the heat conductivity coefficient of the heat exchange wall surface between high-pressure fluid and low-pressure fluid of the pipe-sleeve heat exchanger for the extremely low temperature region composite refrigerator at the base temperature; according to the convective heat transfer experience correlation:
wherein
The solid wall surface heat conductivity coefficient is:
3) and calculating the total heat transfer coefficient of each heat transfer unit of the pipe-in-pipe heat exchanger according to the total heat transfer coefficient calculation method of the dividing wall type heat exchanger.
Wherein k is1Is the wall surface thermal conductivity coefficient, k2Is the high-pressure side fluid convection heat transfer coefficient, k3The heat transfer coefficient is the convection heat transfer coefficient of the fluid at the low-pressure side.
3. The design method of the tube-in-tube heat exchanger for the very low temperature zone composite refrigerator according to claim 1, wherein the third step specifically comprises the following steps:
and calculating the heat exchange area of each heat transfer unit of the tube-in-tube heat exchanger according to an average logarithmic temperature difference method, checking the area of the heat exchanger according to the difference of the tube-in-tube heat exchange areas obtained by two successive iterative calculations, if the heat exchange requirements are met, performing the fourth step, and if the heat exchange requirements are not met, continuing to perform iterative calculation until the heat exchange area check meets the requirements. Because the pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region adopts a spiral pipe structure, certain correction needs to be carried out on the basis of heat exchange of the straight pipe,
4. the design method of the tube-in-tube heat exchanger for the ultra-low temperature area composite refrigerator as claimed in claim 1, wherein the specific process of the fourth step comprises the following steps:
1) determining the actual heat exchange area of the pipe-in-pipe heat exchanger according to the step three, and calculating the fluid pressure drop of the low-pressure side of the pipe-in-pipe heat exchanger through a pressure drop calculation formula of the pipe-in-pipe heat exchanger;
wherein f is friction coefficient, L is tube length, d is tube diameter, in order to further reduce the system structure of the compound refrigerator in the extremely low temperature region, the tube-in-tube heat exchanger adopts a spiral arrangement mode, therefore, certain correction is carried out on the basis of the calculation of the pressure drop of the straight tube,
2) checking resistance pressure drop according to the design requirement of low-pressure side pressure drop of the tube-in-tube heat exchanger for the extremely low temperature area composite refrigerator, and if the resistance pressure drop requirement is met, finishing the calculation; and if the pressure drop design requirement is not met, changing the structural parameters of the tube-in-tube heat exchanger for the composite refrigerator in the ultra-low temperature area, and repeating the second step and the third step to continue calculating until the pressure drop of the low-pressure side of the tube-in-tube heat exchanger for the composite refrigerator in the ultra-low temperature area meets the requirement.
Claims (1)
1. A design method of a pipe-sleeve heat exchanger for a composite refrigerator in an extremely low temperature region is characterized by comprising the following steps:
the method comprises the following steps: designing the pipe-sleeve heat exchanger for the compound refrigerator in the extremely low temperature region by taking the operating condition and the structural parameters of the pipe-sleeve heat exchanger for the compound refrigerator in the extremely low temperature region and the physical property parameters of the fluid as design input parameters;
step two: performing segmented calculation according to the operation condition of the pipe-in-pipe heat exchanger for the composite refrigerator in the ultra-low temperature region, and respectively calculating the enthalpy difference and the average logarithmic temperature difference of the inlet and the outlet of the pipe-in-pipe heat exchanger; calculating the total heat transfer coefficient of the heat exchanger according to the structural parameters of the pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region and the physical property parameters of the fluid; the method specifically comprises the following steps:
1) dividing the pipe-in-pipe heat exchanger into a plurality of sections according to the operation condition of the pipe-in-pipe heat exchanger for the compound refrigerator in the ultra-low temperature region, and calculating the heat exchange quantity and the average logarithmic temperature difference of the heat exchanger according to the inlet and outlet parameters of the pipe-in-pipe heat exchanger and an enthalpy difference method;
2) according to fluid physical parameters and structural parameters in the tube-in-tube heat exchanger for the ultra-low temperature zone composite refrigerator; calculating the convection heat transfer coefficient of high-pressure side fluid in the pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region; calculating the convection heat transfer coefficient of the low-pressure side fluid in the pipe-sleeve heat exchanger for the composite refrigerator in the extremely low temperature region; calculating the heat conductivity coefficient of the heat exchange wall surface between high-pressure fluid and low-pressure fluid of the pipe-sleeve heat exchanger for the extremely low temperature region composite refrigerator at the base temperature;
3) calculating the total heat transfer coefficient of each heat transfer unit of the pipe-in-pipe heat exchanger according to the total heat transfer coefficient calculation method of the dividing wall type heat exchanger;
step three: calculating the area of the pipe-in-pipe heat exchanger according to the enthalpy difference, the average logarithmic temperature difference and the total heat transfer coefficient of the inlet and the outlet of the pipe-in-pipe heat exchanger obtained by sectional calculation, and checking; the method specifically comprises the following steps:
calculating the heat exchange area of each heat transfer unit of the tube-in-tube heat exchanger according to an average logarithmic temperature difference method, checking the area of the heat exchanger according to the difference of the tube-in-tube heat exchange areas obtained by two successive iterative calculations, if the heat exchange requirements are met, performing the fourth step, and if the heat exchange requirements are not met, continuing to perform iterative calculation until the heat exchange area checking meets the requirements;
step four: calculating the total pressure drop of the pipe-in-pipe heat exchanger according to the calculated area of the pipe-in-pipe heat exchanger, the operating condition of the pipe-in-pipe heat exchanger and the fluid physical property parameters, and checking; the method specifically comprises the following steps:
1) determining the actual heat exchange area of the pipe-in-pipe heat exchanger according to the step three, and calculating the fluid pressure drop of the low-pressure side of the pipe-in-pipe heat exchanger through a pressure drop calculation formula of the pipe-in-pipe heat exchanger;
2) checking resistance pressure drop according to the design requirement of low-pressure side pressure drop of the tube-in-tube heat exchanger for the extremely low temperature area composite refrigerator, and if the resistance pressure drop requirement is met, finishing the calculation; and if the pressure drop design requirement is not met, changing the structural parameters of the tube-in-tube heat exchanger for the composite refrigerator in the ultra-low temperature area, and repeating the second step and the third step to continue calculating until the pressure drop of the low-pressure side of the tube-in-tube heat exchanger for the composite refrigerator in the ultra-low temperature area meets the requirement.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110265626.5A CN113239474B (en) | 2021-03-11 | 2021-03-11 | Design method of pipe-sleeve heat exchanger for composite refrigerator in extremely-low temperature region |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110265626.5A CN113239474B (en) | 2021-03-11 | 2021-03-11 | Design method of pipe-sleeve heat exchanger for composite refrigerator in extremely-low temperature region |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113239474A CN113239474A (en) | 2021-08-10 |
| CN113239474B true CN113239474B (en) | 2022-03-29 |
Family
ID=77130277
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110265626.5A Active CN113239474B (en) | 2021-03-11 | 2021-03-11 | Design method of pipe-sleeve heat exchanger for composite refrigerator in extremely-low temperature region |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113239474B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113722900B (en) * | 2021-08-20 | 2023-10-20 | 北京航空航天大学 | Performance design and analysis method for non-design point of aviation heat exchanger |
| CN116205010B (en) * | 2023-05-06 | 2023-07-25 | 常州贺斯特科技股份有限公司 | Unbalanced design and load accounting method for phase-change cooling system by utilizing average logarithmic temperature difference |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101701755A (en) * | 2009-10-20 | 2010-05-05 | 李华玉 | Sectionalized heat absorption, sectionalized compression and sectionalized expansion gas compression type heat pump |
| CN104534719A (en) * | 2014-12-09 | 2015-04-22 | 中国科学院上海技术物理研究所 | Direct-current drive and active temperature control system of two-stage high-frequency pulse tube refrigerator and design method thereof |
| CN106642822A (en) * | 2016-11-25 | 2017-05-10 | 中国科学院上海技术物理研究所 | Secondary intermediate heat exchanger for thermal coupling coaxial two-stage pulse pipe refrigerator and design method |
| CN206973951U (en) * | 2017-05-12 | 2018-02-06 | 包头稀土研究院 | Combined type room-temperature magnetic refrigerator is back and forth exchanged heat with cold end becomes unidirectional heat exchange reversal valve |
| CN207797445U (en) * | 2017-12-29 | 2018-08-31 | 陕西仙童科技有限公司 | A kind of expanding machine and its segmented regenerator |
| CN109959283A (en) * | 2019-03-11 | 2019-07-02 | 中国空气动力研究与发展中心超高速空气动力研究所 | High-temperature cooler heating power check method and system |
| CN110705047A (en) * | 2019-09-16 | 2020-01-17 | 仲恺农业工程学院 | Design calculation method for winding tube type heat exchanger with baffle plate |
| CN111428346A (en) * | 2020-03-03 | 2020-07-17 | 西安交通大学 | Design method of interference-free geothermal heat exchanger comprehensively considering heat exchange-resistance-economic factors |
| CN111561792A (en) * | 2020-01-19 | 2020-08-21 | 华电电力科学研究院有限公司 | Method for recycling industrial low-temperature waste heat for multi-cycle cooling system |
| CN112212719A (en) * | 2020-09-15 | 2021-01-12 | 中国科学院上海技术物理研究所 | Bypass type low-temperature negative pressure heat exchanger for pre-cooling JT (joint temperature) refrigerating machine and design method |
-
2021
- 2021-03-11 CN CN202110265626.5A patent/CN113239474B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101701755A (en) * | 2009-10-20 | 2010-05-05 | 李华玉 | Sectionalized heat absorption, sectionalized compression and sectionalized expansion gas compression type heat pump |
| CN104534719A (en) * | 2014-12-09 | 2015-04-22 | 中国科学院上海技术物理研究所 | Direct-current drive and active temperature control system of two-stage high-frequency pulse tube refrigerator and design method thereof |
| CN106642822A (en) * | 2016-11-25 | 2017-05-10 | 中国科学院上海技术物理研究所 | Secondary intermediate heat exchanger for thermal coupling coaxial two-stage pulse pipe refrigerator and design method |
| CN206973951U (en) * | 2017-05-12 | 2018-02-06 | 包头稀土研究院 | Combined type room-temperature magnetic refrigerator is back and forth exchanged heat with cold end becomes unidirectional heat exchange reversal valve |
| CN207797445U (en) * | 2017-12-29 | 2018-08-31 | 陕西仙童科技有限公司 | A kind of expanding machine and its segmented regenerator |
| CN109959283A (en) * | 2019-03-11 | 2019-07-02 | 中国空气动力研究与发展中心超高速空气动力研究所 | High-temperature cooler heating power check method and system |
| CN110705047A (en) * | 2019-09-16 | 2020-01-17 | 仲恺农业工程学院 | Design calculation method for winding tube type heat exchanger with baffle plate |
| CN111561792A (en) * | 2020-01-19 | 2020-08-21 | 华电电力科学研究院有限公司 | Method for recycling industrial low-temperature waste heat for multi-cycle cooling system |
| CN111428346A (en) * | 2020-03-03 | 2020-07-17 | 西安交通大学 | Design method of interference-free geothermal heat exchanger comprehensively considering heat exchange-resistance-economic factors |
| CN112212719A (en) * | 2020-09-15 | 2021-01-12 | 中国科学院上海技术物理研究所 | Bypass type low-temperature negative pressure heat exchanger for pre-cooling JT (joint temperature) refrigerating machine and design method |
Non-Patent Citations (2)
| Title |
|---|
| 《Theoretical modeling and experimental verifications of the single-compressor-driven three-stage Stirling-type pulse tube cryocooler》;Haizheng Dang等;《Frontiers in Energy》;20180720;全文 * |
| 《用于液氮温区小型节流制冷机的套管式逆流换热器研究》;周振君等;《第十一届全国低温工程大会》;20141125;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113239474A (en) | 2021-08-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113239474B (en) | Design method of pipe-sleeve heat exchanger for composite refrigerator in extremely-low temperature region | |
| CN103542621B (en) | A kind of method for designing of general combination pipe diameter air conditioner heat exchange equipment fluid passage | |
| Wang et al. | Optimization of refrigeration system with gas-injected scroll compressor | |
| JP5243033B2 (en) | High efficiency heat exchanger for refrigeration process | |
| JP2014501381A5 (en) | ||
| CN106524554B (en) | Compact liquid-free helium 1K low-temperature refrigerating device suitable for ultrahigh vacuum environment | |
| CN101226031A (en) | Winding type spiral pipe heat exchanger | |
| WO2014054117A1 (en) | Double-tube heat exchanger and refrigerating cycle device | |
| WO2015059832A1 (en) | Heat exchanger and refrigeration cycle device using said heat exchanger | |
| CN109443061B (en) | Double-spiral fin heat exchanger with dense upper part and sparse lower part | |
| Wang et al. | Reversely-variable circuitry for finned-tube heat exchanger in air source heat pump to enhance its overall energy performance | |
| CN110705047A (en) | Design calculation method for winding tube type heat exchanger with baffle plate | |
| CN112212719B (en) | Bypass type low-temperature negative pressure heat exchanger for pre-cooling JT (joint temperature) refrigerating machine and design method | |
| US10551092B2 (en) | Pulse-tube refrigerator | |
| Zhao et al. | Development of a stepped capillary tube as a low cost throttling device for a residential heat pump system | |
| Rozhentsev et al. | Investigation of the starting modes of the low-temperature refrigerating machines working on the mixtures of refrigerants | |
| CN112906152A (en) | Design method of heat exchange-resistance type slit cold end heat exchanger for composite refrigerator | |
| Kim et al. | Experimental and numerical investigations on continuous pressure drop characteristic of tube-in-tube recuperative heat exchanger for 1.8 K cooler | |
| Chen et al. | Theoretical analysis of the impacts of refrigerant leakage on the performance of a flash tank vapor injection heat pump | |
| JP4867569B2 (en) | Heat exchanger and refrigeration air conditioner | |
| Zhao et al. | Performance analysis of woven wire screen matrix heat exchanger units | |
| KR101620107B1 (en) | Heat exchanger | |
| Qi | Quick and empirical correlations for refrigerant pressure drop in mobile air conditioning system evaporators | |
| CN111561829B (en) | Small-channel parallel pipeline heat exchanger and calculation method | |
| CN212362900U (en) | Parallel pipeline heat exchanger with small channels |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |