A wind-driven direct-drive refrigeration device and design method for protecting permafrost

Abstract

The present invention provides a wind-driven direct-driven refrigeration device and a design method for protecting permafrost, which belongs to the field of permafrost engineering technology. The refrigeration device includes a cabinet and a wind turbine unit installed inside the cabinet, a transmission speed-changing mechanism unit and a refrigeration unit. The wind turbine unit is used to convert wind energy into mechanical energy, the transmission speed-changing mechanism unit is used to increase the speed of the wind turbine unit output and the output speed can be adjusted autonomously, the output speed of the transmission speed-changing mechanism unit is limited within a reasonable range, and the refrigeration unit is used to transport cold to the inside of the permafrost foundation to refrigerate the permafrost and protect the permafrost. The wind-driven direct-driven refrigeration device and a design method for protecting permafrost provided by the present invention solve the technical problem of low energy utilization rate of the equipment and methods used for protecting permafrost in the prior art, and have the technical effects of reducing energy loss, high energy utilization rate, high efficiency of the refrigeration system, and good practicality.

Description

Technical Field

[0001] The present invention belongs to the technical field of permafrost engineering, and more specifically, relates to a wind-driven direct-drive refrigeration device and a design method for protecting permafrost. Background Art

[0002] my country's permafrost is mainly distributed in the Qinghai-Tibet Plateau, the "third pole". Affected by climate warming and engineering activities, the permafrost is in a state of strong degradation. The degradation of permafrost has a significant impact on the subgrade structure of railways and highways. Surveys show that the subgrade diseases caused by the degradation and thawing of permafrost on the Qinghai-Tibet Highway account for more than 75% of the total disease rate. "Protecting permafrost" is the main principle of transportation construction in permafrost areas. The cooling idea of ​​cooling the subgrade is adopted, including broken / block / flaked stone air-cooled structure, ventilation pipes, heat rods and XPS insulation layer. However, in high-temperature, ice-rich permafrost sections or thawing sections that require emergency rescue, the existing measures are not competent. For this reason, artificial refrigeration technology has begun to be introduced in the transportation field to achieve active refrigeration of permafrost areas, that is, more real-time and effective protection. The reverse transfer of heat in the refrigeration cycle requires the drive of external energy (mechanical energy, electrical energy or thermal energy). The infrastructure along the transportation line is unevenly distributed, and the technical and economic feasibility of centralized energy supply faces huge difficulties. Therefore, refrigeration solutions based on new energy sources such as solar energy and wind energy are the main ways to protect permafrost on transportation routes. For example, application number CN201711190185.7 discloses a compression refrigeration system for preventing and controlling permafrost degradation, and proposes an electric compression refrigeration system driven by solar energy and wind energy; application number CN201010005249.3 discloses a method for maintaining thermal stability of permafrost foundations and a matching solar refrigeration device, and proposes a thermal adsorption refrigeration system driven by solar energy.

[0003] The main problems in the above-disclosed documents are: for electric energy-driven refrigeration systems, there are many energy-shape conversion links in solar and wind power generation, and the utilization efficiency of solar and wind energy is relatively low. In order to match the electricity demand of the refrigeration system, the number of power generation components needs to be increased, and the equipment installation area and investment scale need to be increased accordingly; for thermal energy-driven refrigeration systems, solar collectors are limited by seasonal and diurnal fluctuations in solar radiation, and heat storage components need to be added. Chemical heat storage materials have low thermal capacity and poor durability, resulting in increased costs, increased volume, and reduced overall life. Therefore, when facing permafrost scenarios on transportation routes, there are limitations in many aspects such as equipment life, occupied space, and economic investment. It can be seen that improving energy utilization efficiency and simplifying the composition of the refrigeration system are the key to ensuring the practicality of permafrost refrigeration protection technology. Summary of the invention

[0004] The purpose of the present invention is to provide a wind-driven direct-driven refrigeration device and design method for protecting permafrost, aiming to solve the technical problems of low energy utilization, large refrigeration system volume and poor practicality of the equipment and methods used in the prior art for protecting permafrost.

[0005] To achieve the above object, the technical solution adopted by the present invention is: to provide a wind-driven direct-driven refrigeration device for protecting permafrost, comprising:

[0006] The cabinet has a plurality of accommodating cavities formed inside along its height direction;

[0007] A wind turbine unit, installed in the cabinet, for converting wind energy into mechanical energy;

[0008] A transmission speed change mechanism unit is installed in the cabinet and located below the wind turbine unit, and is used to increase the output speed of the wind turbine unit and the output speed can be adjusted autonomously. The output speed of the transmission speed change mechanism unit is limited to a reasonable range;

[0009] A refrigeration unit, installed in the cabinet and located below the transmission and speed change mechanism unit, comprising a condensing heat exchanger arranged around the wind turbine unit, the refrigeration unit is used to convert the rotary motion output by the transmission and speed change mechanism unit into a linear reciprocating motion, and to deliver cold energy to the interior of the permafrost foundation, so as to cool the permafrost and protect the permafrost;

[0010] The air flow of the wind turbine unit is used to accelerate the convection heat dissipation of the condensing heat exchanger to improve the cooling effect.

[0011] In a possible implementation, the wind turbine unit includes:

[0012] The machine base has a mounting hole in the middle;

[0013] A steel tube support, fixedly connected to the upper end of the machine base, and having a hollow interior;

[0014] A rotating shaft is vertically arranged and penetrates the inside of the steel tube bracket, one end of the rotating shaft penetrates and extends above the steel tube bracket, and the other end passes through the mounting hole and extends below the machine base, and the rotating shaft has a circumferential rotational freedom inside the steel tube bracket;

[0015] A fan hub, wherein the upper end of the rotating shaft is connected to the power output end of the fan hub, and the fan hub is used to convert wind energy into mechanical energy. After the fan hub outputs power, the power is transmitted through the rotating shaft;

[0016] A plurality of wind wheel blades are connected to the power input end of the fan hub. The plurality of wind wheel blades are arranged in a circular array and drive the fan hub to operate after rotating.

[0017] In a possible implementation, the transmission speed change mechanism unit includes:

[0018] A gear transmission speed change mechanism, having a power input end and a power output end, wherein the power output end of the wind turbine unit is connected to the power input end of the gear transmission speed change mechanism and is used to transmit input power, the speed of the power output end of the gear transmission speed change mechanism is greater than the speed of its power input end, and the speed of the power output end of the gear transmission speed change mechanism can be adjusted autonomously;

[0019] An output shaft, connected to the power output end of the gear transmission speed change mechanism, for outputting transmission power;

[0020] A speed limiter is connected to the output shaft and is used to limit the output shaft to rotate within a preset speed range. The preset speed range of the speed limiter can be adjusted autonomously.

[0021] In a possible implementation, the refrigeration unit includes:

[0022] A piston compressor, comprising a compression chamber, a piston disposed inside the compression chamber, and a crank-connecting rod mechanism connected to the piston at one end, wherein the other end of the crank-connecting rod mechanism extends outside the compression chamber and is connected to the power output end of the transmission speed change mechanism unit, wherein the transmission speed change mechanism unit is used to transmit input power to the piston compressor, and the crank-connecting rod mechanism is used to convert rotational motion into linear reciprocating motion of the piston;

[0023] Wherein, the compression chamber has an inlet and an outlet, and the compression chamber outlet is connected to the oil separator inlet, the oil separator outlet is connected to the condensing heat exchanger inlet, the condensing heat exchanger outlet is connected to the drying filter inlet, the drying filter outlet is connected to the throttling regulating valve inlet, the throttling regulating valve outlet is connected to the evaporative refrigerator inlet, and the evaporative refrigerator outlet is connected to the compression chamber inlet to form a closed circulation loop, and the closed circulation loop is filled with a coolant. The evaporative refrigerator is installed inside the permafrost foundation to protect the permafrost by transporting cold energy to the inside of the permafrost foundation.

[0024] In a possible implementation, the cabinet includes:

[0025] The cabinet body and sides are all open;

[0026] A plurality of support plates are installed inside the cabinet and spaced apart along the height direction of the cabinet. The plurality of support plates divide the internal space of the cabinet into multiple layers of the accommodating chambers. The wind turbine unit and the condensing heat exchanger are both arranged on the support plate located on the upper layer, the transmission speed change mechanism unit is arranged on the support plate located on the middle layer, and the refrigeration unit is arranged on the support plate located on the lower layer.

[0027] A plurality of ventilation panels are installed on the side of the cabinet and located above the upper support plate;

[0028] A plurality of closed panels are installed on the side of the cabinet and are located above the middle and lower support plates, and are used to close the side openings of the cabinet.

[0029] In a possible implementation, the wind rotor blades are in an airfoil shape and are made of aluminum alloy, and the surfaces of the wind rotor blades are spray-coated.

[0030] In one possible implementation, the condensing heat exchanger is an air-cooled spiral radiator, which is spiral in shape and performs heat exchange and cooling by air convection; the evaporative refrigerator is a conductive column-type heat absorber, which is column-shaped and can achieve cold conduction and cooling of permafrost foundations by direct contact; the coolant is a mixture of lubricating oil and saturated hydrocarbons, and the coolant acts as a carrier to transfer cold. The cooling temperature of the coolant is below -10°C, ensuring the temperature difference level, cold diffusion efficiency and cooling effect of permafrost.

[0031] The beneficial effect of a wind-driven direct-driven refrigeration device for protecting permafrost provided by the present invention is that: compared with the prior art, the wind-driven direct-driven refrigeration device for protecting permafrost provided by the present invention comprises a cabinet, a wind turbine unit, a transmission speed-changing mechanism unit and a refrigeration unit, and a multi-layer accommodating cavity arranged along its height direction is formed inside the cabinet; the wind turbine unit is installed in the cabinet and is used to convert wind energy into mechanical energy; the transmission speed-changing mechanism unit is installed in the cabinet and is located below the wind turbine unit, and is used to increase the output speed of the wind turbine unit, and the output speed can be independently set and adjusted, and the output speed of the transmission speed-changing mechanism unit is limited to a reasonable range; the refrigeration unit is installed in the cabinet and is located below the transmission speed-changing mechanism unit, and is used to convert the rotational motion output by the transmission speed-changing mechanism unit into a linear reciprocating motion, and transport cold to the inside of the permafrost foundation, so that the permafrost is cooled to achieve the protection target, and the technical problems of low energy utilization rate, excessively large volume of the refrigeration system and poor practicality of the equipment and method used for protecting permafrost are solved, and the technical effects of reducing energy loss, high energy utilization rate, high efficiency of the refrigeration system and good practicality are achieved.

[0032] The present invention also provides a design method for a wind-driven direct-drive refrigeration device for protecting permafrost. The design content mainly includes the piston compressor model of the refrigeration unit, the wind wheel blade model of the wind turbine unit, the gear transmission speed change mechanism model and the speed limiter model of the transmission speed change mechanism unit. The design method includes the following steps:

[0033] S1 Calculate and evaluate the cooling load on permafrost foundation;

[0034] S2 Select the piston compressor model of the refrigeration unit of the wind-driven direct-drive refrigeration device; determine the rated input power and torque corresponding to the piston compressor model, the speed range of the crank-connecting rod mechanism and the design parameter values ​​of the upper limit value component;

[0035] S3 Carry out the overall design of the refrigeration unit of the wind-driven direct-drive refrigeration device; according to the selected piston compressor model, complete the design of the refrigeration unit condensing heat exchanger, filter drier, throttling control valve, and evaporative refrigerator selection plan;

[0036] S4 selects a wind rotor blade model of a wind turbine unit of a wind-driven direct-drive refrigeration device; calculates a swept area and a rated speed of the wind rotor blade according to the rated input power and torque corresponding to the piston compressor model selected in S2, and selects a corresponding wind rotor blade model accordingly;

[0037] S5: selecting the gear transmission speed change mechanism model of the transmission speed change mechanism unit of the wind direct drive refrigeration device; according to the speed range of the crank connecting rod mechanism in S2 and the rated speed of the wind wheel blades in S4, the model of the gear transmission speed change mechanism is determined by the ratio of the two;

[0038] S6 Select the speed limiter model of the transmission speed change mechanism unit of the wind direct drive refrigeration device; determine the speed limiter model of the transmission speed change mechanism unit according to the speed upper limit value of the crank connecting rod mechanism in S2;

[0039] S7 designs and selects cabinets for wind-driven direct-drive refrigeration devices.

[0040] In a possible implementation, the swept area of ​​the wind turbine blades of the wind turbine unit depends on the rated input power, wind speed and wind energy utilization coefficient of the piston compressor of the refrigeration unit, and the calculation formula is:

[0041]

[0042] In the formula, P is the rated input power of the piston compressor, W; C p is the wind energy utilization coefficient, which ranges from 0 to 0.45 and is determined based on on-site measurements; ρis the air density, kg / m³, under standard conditions the air density is 1.29 kg / m³; μ is the wind speed, m / s, determined based on on-site measurements and historical meteorological data; A is the swept area of ​​the wind turbine unit, m².

[0043] In a possible implementation, the rotation speed of the wind turbine blades of the wind turbine unit depends on the rated input power and input torque of the refrigeration unit, and the calculation formula is:

[0044]

[0045] In the formula, T is the rated input torque of the refrigeration unit, N·m; n is the wind turbine unit speed, r / min.

[0046] The beneficial effect of the design method of a wind-driven direct-drive refrigeration device for protecting permafrost provided by the present invention is that: compared with the prior art, by calculating the compressor input power and torque of the refrigeration unit and selecting a suitable wind wheel blade model, the output power and output torque of the wind turbine unit are matched with the input power and torque of the refrigeration unit, respectively, so that the piston compressor can be started normally and work within the rated input power and input torque range, preventing the piston compressor from being overloaded. The present invention has the technical effects of reducing energy loss, high energy utilization, high refrigeration system efficiency, and good practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1 A schematic diagram of the structure of a wind-driven direct-drive refrigeration device for protecting permafrost provided by an embodiment of the present invention;

[0049] Figure 2 A schematic structural diagram of a wind turbine unit of a wind-driven direct-drive refrigeration device for protecting permafrost provided by an embodiment of the present invention;

[0050] Figure 3 A schematic structural diagram of a transmission speed change mechanism unit of a wind-driven direct-drive refrigeration device for protecting permafrost provided by an embodiment of the present invention;

[0051] Figure 4A schematic diagram of the structure of a refrigeration unit of a wind-driven direct-drive refrigeration device for protecting permafrost provided by an embodiment of the present invention;

[0052] Figure 5 A three-dimensional diagram of a wind-driven direct-drive refrigeration device for protecting permafrost provided by an embodiment of the present invention;

[0053] Figure 6 A three-dimensional diagram of an application scenario of a wind-driven direct-drive refrigeration device for protecting permafrost provided in an embodiment of the present invention.

[0054] Description of reference numerals:

[0055] 1. Cabinet; 11. Accommodation cavity; 12. Cabinet body; 13. Pallet;

[0056] 2. Wind turbine unit; 21. Machine base; 22. Steel tube bracket; 23. Rotating shaft; 24. Wind turbine hub; 25. Wind rotor blades;

[0057] 3. Transmission speed change mechanism unit; 31. Gear transmission speed change mechanism; 32. Output shaft; 33. Speed ​​limiter; 34. Coupling;

[0058] 4. Refrigeration unit; 41. Piston compressor; 411. Compression chamber; 412. Piston; 413. Crank-connecting rod mechanism; 42. Oil separator; 43. Condensing heat exchanger; 44. Dry filter; 45. Throttle regulating valve; 46. Evaporative refrigerator;

[0059] 5. Roadbed;

[0060] 6. Permafrost foundation. DETAILED DESCRIPTION

[0061] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0062] Please also read Figures 1 to 6Now, a wind-driven direct-drive refrigeration device and a design method for protecting permafrost provided by the present invention are described. The wind-driven direct-drive refrigeration device for protecting permafrost comprises a cabinet 1, a wind turbine unit 2, a transmission speed-changing mechanism unit 3 and a refrigeration unit 4. A multi-layer accommodating cavity 11 arranged along the height direction of the cabinet 1 is formed inside the cabinet 1; the wind turbine unit 2 is installed in the cabinet 1 and is used to convert wind energy into mechanical energy; the transmission speed-changing mechanism unit 3 is installed in the cabinet 1 and is located below the wind turbine unit 2, and is used to increase the output speed of the wind turbine unit 2, and the output speed can be set and adjusted independently, and the output speed of the transmission speed-changing mechanism unit 3 is limited to a reasonable range; the refrigeration unit 4 is installed in the cabinet 1 and is located below the transmission speed-changing mechanism unit 3, and comprises a condensing heat exchanger 43 arranged around the wind turbine unit 2, and the refrigeration unit 4 is used to convert the rotational motion output by the transmission speed-changing mechanism unit 3 into a linear reciprocating motion, thereby driving the refrigeration cycle process and transmitting cold to the inside of the permafrost foundation 6, so as to cool the permafrost and protect the permafrost; wherein the air flow of the wind turbine unit 2 is used to accelerate the convection heat dissipation of the condensing heat exchanger 43 to improve the refrigeration effect.

[0063] The wind-driven direct-drive refrigeration device for protecting permafrost provided by the present invention solves the technical problems of low energy utilization rate, large refrigeration system volume and poor practicability of the equipment and methods used for protecting permafrost, compared with the prior art, and has the technical effects of reducing energy loss, high energy utilization rate, high refrigeration system efficiency and good practicability.

[0064] In some embodiments, see Figures 1 to 6The wind turbine unit 2 includes a machine base 21, a steel tube bracket 22, a rotating shaft 23, a fan hub 24 and a plurality of wind rotor blades 25. A mounting hole is provided in the middle of the machine base 21; the steel tube bracket 22 is fixedly connected to the upper end of the machine base 21, and a hollow is formed inside; the rotating shaft 23 is vertically arranged and penetrates the inside of the steel tube bracket 22, one end of the rotating shaft 23 passes through and extends above the steel tube bracket 22, and the other end passes through the mounting hole and extends below the machine base 21, and the rotating shaft 23 has a degree of freedom of rotation around its circumferential direction inside the steel tube bracket 22; the upper end of the rotating shaft 23 is connected to the power output end of the fan hub 24, and the fan hub 24 is used to convert wind energy into mechanical energy. After the fan hub 24 outputs power, it transmits power through the rotating shaft 23; a plurality of wind rotor blades 25 are all connected to the power input end of the fan hub 24, and the plurality of wind rotor blades 25 are arranged in a ring array and drive the fan hub 24 to operate after rotation. Multiple wind rotor blades 25 are fixed to the fan hub 24 by anti-loosening bolts. When there is wind energy, multiple wind rotor blades 25 will be driven to rotate. The rotating shaft 23 is fixed to the fan hub 24 by a flange as a power output component. The steel tube bracket 22 is a steel tube or cylindrical structure, and the rotating shaft 23 can pass through its interior, or a bearing is installed in the steel tube bracket 22, and the rotating shaft 23 is sleeved in the bearing, so that the rotating shaft 23 can be stably rotated in the circumferential direction inside the steel tube bracket 22, and will not move up and down during the rotation process. The machine base 21 plays a role in supporting the steel tube bracket 22, and the fan hub 24 can also be fixed to the machine base 21 through a bracket. The rotating shaft 23 is arranged vertically, with the upper end connected to the fan hub 24 and the lower end used to connect to the power output end of the transmission speed change mechanism unit 3.

[0065] In some embodiments, see Figures 1 to 6The transmission speed change mechanism unit 3 includes a gear transmission speed change mechanism 31, an output shaft 32 and a speed limiter 33. The gear transmission speed change mechanism 31 has a power input end and a power output end. The power output end of the wind turbine unit 2 is connected to the power input end of the gear transmission speed change mechanism 31 and is used to transmit the input power. The speed of the power output end of the gear transmission speed change mechanism 31 is greater than the speed of its power input end. The speed of the power output end of the gear transmission speed change mechanism 31 can be set and adjusted independently; the output shaft 32 is connected to the power output end of the gear transmission speed change mechanism 31 for outputting the transmitted power; the speed limiter 33 is connected to the output shaft 32 for limiting the output shaft 32 to rotate within a preset speed range. The preset speed range of the speed limiter 33 can be set and adjusted independently. Specifically, the lower end of the rotating shaft 23 is connected to the power input end of the gear transmission speed change mechanism 31 through a coupling 34. The gear transmission speed change mechanism 31 is a speed increaser, including a first-stage cylindrical gear, a second-stage cylindrical gear, and a hydraulic transmission. The lower end of the rotating shaft 23 is connected to the first-stage cylindrical gear through a coupling 34, and the second-stage cylindrical gear is connected to the output shaft 32 through the coupling 34. The first-stage cylindrical gear and the second-stage cylindrical gear are meshed, and the gear ratio is 1: N , N It is determined based on precise design calculations, and its function is to convert the low-speed rotating shaft 23 into a high-speed rotating output shaft 32. The gear ratio is 1: N The design calculation method is the ratio of the rated speed of the wind turbine unit wind wheel blades to the speed range requirement of the compressor crank-connecting rod mechanism. The I-level cylindrical gear and the II-level cylindrical gear are adjusted by a hydraulic transmission. The function of the hydraulic transmission is to smoothly adjust the speed of the output shaft 32. Its working principle is to inject high-density liquid. When the speed changes, the liquid density will change accordingly, thereby achieving smooth regulation of mechanical energy transmission and achieving the effect of automatic stepless speed change. When the wind speed is low, the speed ratio automatically decreases, and when the wind speed is high, the speed ratio automatically increases. At the same time, by setting the speed limiter 33, the reason is that when the wind turbine unit 2 is working, the environment is greatly affected by the natural wind conditions, and sometimes it is hit by sudden gusts or strong winds. The purpose of the speed limiter 33 is to ensure the safe and reliable operation of the wind turbine unit 2 and the refrigeration unit 4.

[0066] The gear transmission speed change mechanism 31 can also adopt a gear transmission or a combination of a speed increaser and a transmission in the prior art, which can realize stepless adjustment of the rotation speed. It should be noted that the output rotation speed should be higher than the input rotation speed.

[0067] In some embodiments, see Figures 1 to 6The refrigeration unit 4 includes a piston compressor 41, which includes a compression chamber 411, a piston 412 disposed inside the compression chamber 411, and a crank-connecting rod mechanism 413 connected to the piston 412 at one end, the other end of the crank-connecting rod mechanism 413 extends to the outside of the compression chamber 411 and is connected to the power output end of the transmission speed change mechanism unit 3, the transmission speed change mechanism unit 3 is used to transmit input power to the piston compressor 41, and the crank-connecting rod mechanism 413 is used to convert the rotational motion into the linear reciprocating motion of the piston 412; wherein the compression chamber 411 has an inlet and an outlet, and the outlet of the compression chamber 411 is connected to the oil separator The inlet 42 and the outlet of the oil separator 42 are connected to the inlet of the condensing heat exchanger 43, the outlet of the condensing heat exchanger 43 is connected to the inlet of the drying filter 44, the outlet of the drying filter 44 is connected to the inlet of the throttling regulating valve 45, the outlet of the throttling regulating valve 45 is connected to the inlet of the evaporative refrigerator 46, and the outlet of the evaporative refrigerator 46 is connected to the inlet of the compression chamber 411, forming a closed circulation loop. The closed circulation loop is filled with a coolant. The evaporative refrigerator 46 is located inside the permafrost foundation 6 under the roadbed, and can be set in an inclined shape, horizontal shape, or vertical shape. It protects the permafrost by transporting cold energy to the inside of the permafrost foundation 6. The above-mentioned compression chamber 411, oil separator 42, condensing heat exchanger 43, drying filter 44, throttling control valve 45 and evaporative refrigerator 46 are all products of existing technology, and are connected to each other through pipelines to form a closed circulation loop. The crank connecting rod mechanism 413 drives the piston 412 to move back and forth, pushing the refrigerant to move into the evaporative refrigerator 46, and then transferring the cold to the evaporative refrigerator 46 to achieve the refrigeration effect and achieve the goal of protecting permafrost. The piston compressor 41 can adopt existing technology products, and its working chamber is the compression chamber 411. Other structures can refer to the existing technology. Figure 4 The arrow in the figure indicates the moving direction of the coolant.

[0068] In some embodiments, see Figures 1 to 6The cabinet 1 includes a cabinet body 12, a plurality of pallets 13, a plurality of ventilation panels (not shown in the figure) and a plurality of closed panels (not shown in the figure). The sides of the cabinet body 12 are open. The purpose of this structural form is to facilitate the installation and subsequent maintenance of each functional unit; a plurality of pallets 13 are installed inside the cabinet body 12 and are arranged at intervals along the height direction of the cabinet body 12. The plurality of pallets 13 divide the internal space of the cabinet body 12 into a multi-layer accommodating chamber 11. The wind turbine unit 2 and the condensing heat exchanger 43 are both arranged on the upper layer. The transmission speed change mechanism unit 3 is arranged on the middle-layered tray 13, and the refrigeration unit 4 is arranged on the lower-layered tray 13. The purpose of this structural form is to enable each functional unit to have an independent operating environment and prevent mutual interference between mechanical moving parts and heat exchange parts; multiple ventilation panels are installed on the side of the cabinet 12 and located above the upper tray 13; multiple closed panels are installed on the side of the cabinet 12 and located above the middle-layer and lower-layer trays 13, used to close the side opening of the cabinet 12. There are three trays 13, which are arranged horizontally, and their sizes can be large or small. They are fixedly connected to the inner wall of the cabinet 12. The three trays 13 divide the interior of the cabinet 12 into four accommodating chambers 11. The accommodating chamber 11 located at the bottom layer is a cavity, which is used to prevent water from accumulating at the foot of the roadbed slope and submerging the refrigeration device; the multi-layer accommodating chambers 11 are arranged from top to bottom in sequence as the wind turbine unit 2, the transmission speed change mechanism unit 3 and the refrigeration unit 4, and the height of the installation of the tray 13 can be adjusted. In order to ensure that wind energy can enter the accommodating cavity 11 located in the upper layer and blow the wind turbine unit 2 to operate, a ventilation panel is arranged on the side of the cabinet 12, so as not to block the wind force, improve the wind energy capture efficiency of the wind turbine unit, and not affect normal use. The closed panel can block the wind force, and can play a role in isolating and protecting the transmission speed change mechanism unit 3 and the refrigeration unit 4, protecting their mechanical motion components from being affected by external factors such as wind and dust. The cabinet 12 is in the shape of a rectangular parallelepiped, and its sides are respectively the left side, the right side, the front side and the rear side. The support plate 13 has four end edges, and three of the end edges can be connected to the inner wall of the cabinet 12 to be fixed. The purpose of placing the wind turbine unit 2 and the condensing heat exchanger 43 on the same layer is to use the air flow under the action of the wind wheel blades 25 to accelerate the convective heat dissipation of the condensing heat exchanger 43 and improve the cooling effect.

[0069] Preferably, the support plate 13 is provided with a mounting hole, through which the output shaft 32 and the rotating shaft 23 can pass, and the hole size should match the diameter of the output shaft 32 and the rotating shaft 23. The support plate 13 is provided with a mounting hole, through which the pipeline can pass.

[0070] In some embodiments, see Figures 1 to 6 The rotor blade 25 is in an airfoil shape and is made of aluminum alloy. The surface of the rotor blade 25 is sprayed with plastic. The airfoil shape can solve the yaw problem of the wind turbine unit 2 during operation. The aluminum alloy material plays a role of lightness and high efficiency, and the spraying treatment plays a role of corrosion resistance.

[0071] In some embodiments, see Figures 1 to 6 The condensing heat exchanger 43 is an air-cooled spiral radiator, which is spiral in shape and is cooled by air convection cooling; the evaporative refrigerator 46 is a conductive column heat absorber, which is column in shape and can achieve cold conduction and cool the permafrost foundation by direct contact with the permafrost; the coolant is a mixture of lubricating oil and saturated hydrocarbons, with a mass ratio of 1:3 to 1:5, in which the lubricating oil plays a role in lubricating and cooling the reciprocating friction of the piston in the compression chamber, and the saturated hydrocarbons mainly play a role in exchanging heat in the condensing heat exchanger 43 and the evaporative refrigerator 46. The main advantage of saturated hydrocarbons is that they are suitable for low-temperature refrigeration needs, with a refrigeration temperature as low as -60°C, and there is no greenhouse effect, which is green and environmentally friendly. The coolant acts as a carrier to transfer cold. The cooling temperature of the coolant is below -10°C and can be adjusted autonomously according to the needs of permafrost protection. The adjustment method is to adjust the cooling temperature level through the mass ratio of lubricating oil and saturated hydrocarbons to ensure the temperature difference level, cold diffusion efficiency and cooling effect of permafrost.

[0072] The present invention also provides a design method for a wind-driven direct-drive refrigeration device for protecting permafrost. The design content mainly includes the model of the compressor (piston compressor 41) of the refrigeration unit 4, the model of the wind wheel blade 25 of the wind turbine unit 2, the model of the gear transmission speed change mechanism 31 and the model of the speed limiter 33 of the transmission speed change mechanism unit 3, and includes the following steps:

[0073] S1 Calculate and evaluate the cooling load on permafrost foundation;

[0074] S2 Select the model of the piston compressor 41 of the refrigeration unit 4 of the wind-driven refrigeration device; determine the rated input power and torque corresponding to the model of the piston compressor 41, the speed range of the crank-connecting rod mechanism 413, and the design parameter values ​​of the upper limit value component;

[0075] S3 performs overall design of the refrigeration unit 4 of the wind-driven refrigeration device; based on the selected piston compressor 41 model, completes the design of the condensing heat exchanger 43, the drying filter 44, the throttling regulating valve 45, and the evaporative refrigerator 46 of the refrigeration unit 4;

[0076] S4: selecting the model of the wind rotor blade 25 of the wind turbine unit 2 of the wind direct-driven refrigeration device; calculating the swept area and rated speed of the wind rotor blade 25 according to the rated input power and torque corresponding to the piston compressor 41 model selected in S2, and selecting the corresponding model of the wind rotor blade 25 accordingly;

[0077] S5: selecting the model of the gear transmission speed change mechanism 31 of the transmission speed change mechanism unit 3 of the wind direct drive refrigeration device; according to the speed range of the crank connecting rod mechanism 413 in S2 and the rated speed of the wind wheel blade 25 in S4, determining the model of the gear transmission speed change mechanism 31 by the ratio of the two;

[0078] S6 Select the speed limiter 33 model of the transmission speed change mechanism unit 3 of the wind direct drive refrigeration device; determine the speed limiter 33 model of the transmission speed change mechanism unit 3 according to the upper limit value of the rotation speed of the crank connecting rod mechanism 413 in S2;

[0079] S7 performs design and selection of cabinet 1 of the wind direct-drive refrigeration device.

[0080] The beneficial effect of the design method of a wind-driven direct-drive refrigeration device for protecting permafrost provided by the present invention is that: compared with the prior art, by calculating the compressor input power and torque of the refrigeration unit 4, a suitable wind wheel blade 25 model is selected, so that the output power and output torque of the wind turbine unit 2 are matched with the input power and torque of the refrigeration unit 4, respectively, so that the piston compressor 41 can be started normally and work within the rated input power and input torque range, and the piston compressor 41 is prevented from being overloaded. The present invention has the technical effects of reducing energy loss, high energy utilization, high efficiency of the refrigeration system, and good practicality.

[0081] In the above S1, the target temperature of permafrost protection is set according to the degree of permafrost warming and degradation, and the heat storage calculation formula in heat transfer theory is used to calculate the cooling capacity required per unit area of ​​permafrost foundation and the cooling load corresponding to different times.

[0082] In the above S2, according to the permafrost foundation scenario, the permafrost protection range of a single device (i.e., the wind-driven direct-driven refrigeration device of the present invention) is planned, and the rated refrigeration power of the refrigeration unit 4 is obtained by multiplying it with the permafrost foundation heat load in S1, and the compressor model with the corresponding rated refrigeration power is selected accordingly. According to the selected compressor model, first, the rated input power and torque corresponding to the piston compressor 41 model are determined through the product manual; second, the design parameter values ​​of the components such as the volume of the compression chamber (piston compressor 41), the area of ​​the piston, the speed range and upper limit of the crank-connecting rod mechanism, etc. are determined through the relevant design manual.

[0083] In the above S7, the geometric dimensions of the upper accommodating cavity 11 of the cabinet 1 are determined according to the selection scheme of the wind turbine unit 2 in S5; the geometric dimensions of the middle accommodating cavity 11 of the cabinet 1 are determined according to the selection scheme of the transmission speed change mechanism unit 3 in S5 and S6; and the geometric dimensions of the lower accommodating cavity 11 of the cabinet 1 are determined according to the selection scheme of the transmission speed change mechanism unit 3 in S2 and S3.

[0084] In some embodiments, the swept area of ​​the wind wheel blades 25 of the wind turbine unit 2 depends on the rated input power, wind speed and wind energy utilization coefficient of the piston compressor 41 of the refrigeration unit 4, and the calculation formula is:

[0085]

[0086] In the formula, P is the rated input power of the piston compressor, W; C p is the wind energy utilization coefficient, which ranges from 0 to 0.45 and is determined based on on-site measurements; ρ is the air density, kg / m³, under standard conditions the air density is 1.29 kg / m³; μ is the wind speed, m / s, determined based on on-site measurements and historical meteorological data; A is the swept area of ​​the wind turbine unit, m².

[0087] In some embodiments, the rotation speed of the wind turbine blades 25 of the wind turbine unit 2 depends on the rated input power and input torque of the refrigeration unit 4, and the calculation formula is:

[0088]

[0089] In the formula, T is the rated input torque of the refrigeration unit, N·m; n is the wind turbine unit speed, r / min.

[0090] In the design process of the refrigeration device, the output power and output torque of the wind turbine unit 2 should simultaneously meet the input power and torque requirements of the piston compressor 41 of the refrigeration unit 4, so that the piston compressor 41 can operate smoothly. Specifically, the wind energy utilization coefficient is determined by the form and rotation speed of the wind rotor blade 25, generally between 0-0.45, and is determined based on on-site measurements; ρ is the air density, kg / m³, under standard conditions (0℃, 1 standard atmospheric pressure 1atm), the air density is about 1.29 kg / m³, and is specifically determined according to the local altitude and other geographical conditions; μ is the wind speed, m / s, which is determined based on on-site measurements and historical meteorological data; A is the wind turbine swept area, m². The swept area of ​​the wind turbine unit 2 is the projected area of ​​the circle generated by the tip movement of the wind rotor blade 25 when it rotates on a plane perpendicular to the wind direction, that is, the area of ​​wind energy intercepted by the wind turbine unit 2. The swept area of ​​the wind turbine unit 2 is determined by the geometric form, installation scheme and geometric dimensions of the wind rotor blade 25.

[0091] Generally, the stroke of the piston compressor 41 is fixed, and as the piston 412 rotates n 0 increases, the driving power consumed PFor different types of piston compressors 41, the rated input power P 0 and torque T 0. Input power P 0. Torque T 0. Piston 412 speed n 0 is expressed by the second formula. The speed of the compressor piston 412 should be maintained at 1500-3000 r / min, which is higher than the wind turbine speed. The speed of the wind rotor blade 25 is directly related to the wind speed. Under different wind speed conditions, the maximum output power and torque are obtained corresponding to the optimal wind rotor speed. For a certain model (rated output power) of wind turbine unit 2, speed control is very important. Therefore, it is necessary to determine the model of the piston compressor 41 according to the permafrost refrigeration demand. First, it is necessary to match the gear ratio of the transmission speed change mechanism unit 3 to 1 according to the rated speed range of the piston compressor 41 and the speed level of the wind turbine unit 2: N Second, the output power and torque of the wind turbine unit 2 meet the rated input power and torque of the piston compressor 41 to ensure that the piston compressor 41 can start normally under the drive of the wind turbine unit 2 and work within the rated input power and torque range to prevent the piston compressor 41 from overloading.

[0092] Due to the adoption of the above structure, the present invention has achieved the following technical progress compared with the prior art: (1) The wind turbine is used to convert wind energy into mechanical energy, and then the compressor is directly driven to move through the speed change mechanism to realize the refrigeration cycle. The improved refrigeration method eliminates the steps of converting mechanical energy into electrical energy and then converting electrical energy into mechanical energy, thereby reducing the energy loss during the conversion process. (2) A speed change mechanism (i.e., transmission speed change mechanism unit 3) is provided between the wind turbine unit 2 and the piston compressor 41 of the refrigeration unit 4, so that the rotation speed of the wind turbine unit 2 can match the rotation speed of the piston compressor 41 of the refrigeration unit 4.

[0093] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A wind-driven direct-drive refrigeration device for protecting permafrost, characterized in that: include: The cabinet has a plurality of accommodating cavities formed inside along its height direction; A wind turbine unit, installed in the cabinet, for converting wind energy into mechanical energy; A transmission speed change mechanism unit is installed in the cabinet and located below the wind turbine unit, and is used to increase the output speed of the wind turbine unit and the output speed can be adjusted autonomously. The output speed of the transmission speed change mechanism unit is limited to a reasonable range; A refrigeration unit is installed in the cabinet and is located below the transmission and speed change mechanism unit, and includes a condensing heat exchanger arranged around the wind turbine unit, the refrigeration unit is used to convert the rotational motion output by the transmission and speed change mechanism unit into a linear reciprocating motion, and to transmit cold energy to the interior of the permafrost foundation, so as to cool the permafrost and protect the permafrost; Wherein, the air flow of the wind turbine unit is used to accelerate the convection heat dissipation of the condensing heat exchanger to improve the cooling effect; The wind turbine unit comprises: The base has a mounting hole in the middle; A steel tube support, fixedly connected to the upper end of the machine base, and having a hollow interior; A rotating shaft is vertically arranged and penetrates the inside of the steel tube bracket, one end of the rotating shaft penetrates and extends above the steel tube bracket, and the other end passes through the mounting hole and extends below the machine base, and the rotating shaft has a circumferential rotational freedom inside the steel tube bracket; A fan hub, wherein the upper end of the rotating shaft is connected to the power output end of the fan hub, and the fan hub is used to convert wind energy into mechanical energy. After the fan hub outputs power, the power is transmitted through the rotating shaft; A plurality of wind wheel blades are connected to the power input end of the fan hub, and the plurality of wind wheel blades are arranged in a circular array and drive the fan hub to operate after rotating; The transmission speed change mechanism unit comprises: A gear transmission speed change mechanism, having a power input end and a power output end, wherein the power output end of the wind turbine unit is connected to the power input end of the gear transmission speed change mechanism and is used to transmit input power, the speed of the power output end of the gear transmission speed change mechanism is greater than the speed of its power input end, and the speed of the power output end of the gear transmission speed change mechanism can be independently set and adjusted; An output shaft, connected to the power output end of the gear transmission speed change mechanism, for outputting transmission power; A speed limiter connected to the output shaft and used to limit the output shaft to rotate within a preset speed range, and the preset speed range of the speed limiter can be adjusted autonomously; The refrigeration unit comprises: A piston compressor, comprising a compression chamber, a piston disposed inside the compression chamber, and a crank-connecting rod mechanism connected to the piston at one end, wherein the other end of the crank-connecting rod mechanism extends outside the compression chamber and is connected to the power output end of the transmission speed change mechanism unit, wherein the transmission speed change mechanism unit is used to transmit input power to the piston compressor, and the crank-connecting rod mechanism is used to convert rotational motion into linear reciprocating motion of the piston; Wherein, the compression chamber has an inlet and an outlet, and the compression chamber outlet is connected to the oil separator inlet, the oil separator outlet is connected to the condensing heat exchanger inlet, the condensing heat exchanger outlet is connected to the drying filter inlet, the drying filter outlet is connected to the throttling regulating valve inlet, the throttling regulating valve outlet is connected to the evaporative refrigerator inlet, and the evaporative refrigerator outlet is connected to the compression chamber inlet to form a closed circulation loop, and the closed circulation loop is filled with a coolant. The evaporative refrigerator is installed inside the permafrost foundation to protect the permafrost by transporting cold energy to the inside of the permafrost foundation.

2. A wind-driven direct-drive refrigeration device for protecting permafrost according to claim 1, characterized in that: The cabinet comprises: The cabinet body and sides are all open; A plurality of support plates are installed inside the cabinet and spaced apart along the height direction of the cabinet. The plurality of support plates divide the internal space of the cabinet into multiple layers of the accommodating chambers. The wind turbine unit and the condensing heat exchanger are both arranged on the support plate located on the upper layer, the transmission speed change mechanism unit is arranged on the support plate located on the middle layer, and the refrigeration unit is arranged on the support plate located on the lower layer. A plurality of ventilation panels are installed on the side of the cabinet and located above the upper support plate; A plurality of closed panels are installed on the side of the cabinet and are located above the middle and lower support plates, and are used to close the side openings of the cabinet.

3. A wind-driven direct-drive refrigeration device for protecting permafrost according to claim 1, characterized in that: The wind wheel blades are in an airfoil shape and are made of aluminum alloy. The surfaces of the wind wheel blades are spray-coated.

4. A wind-driven direct-drive refrigeration device for protecting permafrost according to claim 1, characterized in that: The condensing heat exchanger is an air-cooled spiral radiator, which is spiral in shape and is cooled by air cooling; the evaporative refrigerator is a conductive column heat absorber, which is column in shape and can achieve cold conduction and heat absorption; the coolant is a mixture of lubricating oil and saturated hydrocarbons, and the coolant acts as a carrier to transfer cold.

5. A design method for a wind-driven direct-drive refrigeration device for protecting permafrost according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1 Calculate and evaluate the cooling load on permafrost foundation; S2 Select the piston compressor model of the refrigeration unit of the wind-driven direct-drive refrigeration device; determine the rated input power and torque corresponding to the piston compressor model, the speed range of the crank-connecting rod mechanism and the design parameter values ​​of the upper limit value component; S3 Carry out the overall design of the refrigeration unit of the wind-driven direct-drive refrigeration device; according to the selected piston compressor model, complete the design of the refrigeration unit condensing heat exchanger, filter drier, throttling control valve, and evaporative refrigerator selection plan; S4 selects a wind rotor blade model of a wind turbine unit of a wind-driven direct-drive refrigeration device; calculates a swept area and a rated speed of the wind rotor blade according to the rated input power and torque corresponding to the piston compressor model selected in S2, and selects a corresponding wind rotor blade model accordingly; S5: selecting the gear transmission speed change mechanism model of the transmission speed change mechanism unit of the wind direct drive refrigeration device; according to the speed range of the crank connecting rod mechanism in S2 and the rated speed of the wind wheel blades in S4, the model of the gear transmission speed change mechanism is determined by the ratio of the two; S6 Select the speed limiter model of the transmission speed change mechanism unit of the wind direct drive refrigeration device; determine the speed limiter model of the transmission speed change mechanism unit according to the speed upper limit value of the crank connecting rod mechanism in S2; S7 designs and selects cabinets for wind-driven direct-drive refrigeration devices.

6. A design method for a wind-driven direct-drive refrigeration device for protecting permafrost according to claim 5, characterized in that: The swept area of ​​the wind turbine unit's wind rotor blades depends on the rated input power, wind speed and wind energy utilization coefficient of the piston compressor of the refrigeration unit, and the calculation formula is: In the formula, P is the rated input power of the piston compressor, W; C p is the wind energy utilization coefficient, which ranges from 0 to 0.45 and is determined based on on-site measurements; ρ is the air density, kg / m³, under standard conditions the air density is 1.29 kg / m³; μ is the wind speed, m / s, determined based on on-site measurements and historical meteorological data; A is the swept area of ​​the wind turbine unit, m².

7. A design method for a wind-driven direct-drive refrigeration device for protecting permafrost according to claim 6, characterized in that: The rotation speed of the wind turbine blades depends on the rated input power and input torque of the refrigeration unit, and the calculation formula is: In the formula, T is the rated input torque of the refrigeration unit, N·m; n is the wind turbine unit speed, r / min.

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