Plate-fin type phase-change heat storage device based on coupling of stepped fins and stepped phase-change materials
By coupling the tiered fins with the tiered phase change material, the problem of insufficient heat storage power in the directed energy weapon thermal management system under high heat load conditions was solved, achieving efficient heat management and temperature control, and improving the system's thermal management efficiency.
Patent Information
- Application Number
- CN202511730026.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-24
- Publication Date
- 2026-02-06
AI Technical Summary
The thermal management system of directed energy weapons is difficult to manage effectively under high heat load conditions. Traditional phase change thermal storage systems have insufficient thermal storage power due to spacecraft size and weight limitations, and cannot meet the requirements for efficient thermal management.
The plate-fin phase change thermal energy storage device adopts a tiered fin coupling with a tiered phase change material. Through the matching design of the tiered fins and the phase change material, it ensures that the fluid temperature is always higher than the melting point of the phase change material, and gradually lowers the melting point to match the fluid temperature changes. It utilizes the high latent heat of the phase change material for effective heat management.
It significantly improves the thermal storage power of the heat fluid and phase change material, enhances the temperature control capability, reduces fluid temperature fluctuations, and optimizes the efficiency of the thermal management system.
Smart Images
Figure CN121474915A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of phase change heat storage, in particular to a plate-fin type phase change heat storage device based on coupling of stepped fins and stepped phase change materials. BACKGROUND
[0002] The directed energy weapon is an advanced weapon system, and its working principle is to use high-energy laser, microwave or particle beam and other energy forms to implement precise attack and interception on the target at the speed close to the speed of light. The wide application of such weapons indicates that energy war is likely to become the main form of future war. However, the energy conversion rate of the existing directed energy weapon is only 20-35%, and most of the energy is dissipated in the form of heat. The heat emitted during each operation reaches 10 6 W, and the local heat flux density is between 100-750 W / cm 2 If this heat is not properly managed, it may cause damage to the system structure and electronic components, and affect the performance and reliability of the weapon. Therefore, effective heat management is crucial to ensure the normal operation of the directed energy weapon. Since the heat load of the directed energy weapon has a pulsating characteristic, the high heat load lasts for a short time within a pulsating cycle. If the heat management design is based on the instantaneous peak heat load, the required cooling system will be very large, which is contradictory to the volume and weight requirements of the equipment in the limited airborne environment. The phase change heat storage technology can solve this problem.
[0003] The traditional phase change heat storage system uses the high latent heat of the phase change material and the characteristic that the temperature is basically unchanged during the phase change process to control the fluid temperature. However, under the condition that the size and weight of the spacecraft are strictly limited, the heat storage power of these systems needs to be further optimized. SUMMARY
[0004] The present application provides a plate-fin type phase change heat storage device based on coupling of stepped fins and stepped phase change materials, which uses coupling of stepped fins and stepped phase change materials to ensure that the high latent heat of the phase change material is fully utilized during the flow of the fluid. When the high-temperature fluid enters the heat storage system, the heat is first conducted from the fluid to the high-melting-point phase change material, triggering the phase change process. As the temperature of the fluid gradually decreases along the flow path, the fluid is still in a superheated state relative to the melting point of the phase change material when it contacts the phase change material with a lower melting point, which allows the remaining heat in the fluid to be effectively absorbed by the phase change material. When the fin spacing is reduced, the unit thermal resistance is also gradually reduced, which is more conducive to temperature conduction.
[0005] The plate-fin type phase change heat storage device based on coupling of stepped fins and stepped phase change materials provided by the present application comprises an inlet portion, a heat storage portion and an outlet portion. The heat storage part comprises multiple layers of heat fluid and phase change heat storage layer arranged in intervals; The phase change heat storage layer is a coupling structure of stepped fins and stepped phase change materials, the stepped fins and the stepped phase change materials are arranged in at least three levels along the flow direction, and are coupled in each level correspondingly; The width interval of the stepped fins decreases gradually along the flow direction, and the melting point of the stepped phase change materials decreases gradually along the flow direction.
[0006] Further, the heat fluid layer and the phase change heat storage layer are arranged alternately.
[0007] Further, the heat storage part is divided into multiple layers by horizontal partitions, and the heat fluid layer and the phase change heat storage layer are arranged in independent layers respectively.
[0008] Further, each level of the stepped fins is formed by S-shaped connection of straight fins to form multiple phase change material cavities with equal intervals, and the stepped phase change materials are filled in the phase change material cavities, and each phase change material cavity is closed by a partition at both ends along the flow direction.
[0009] Further, the stepped phase change materials account for 64% of the volume of the phase change heat storage layer.
[0010] Further, the heat fluid layer is formed into a heat fluid channel by sawtooth fins.
[0011] Further, the inlet part and the outlet part are both round rectangular column structures.
[0012] Further, the stepped fins and the stepped phase change materials are arranged in three levels along the flow direction; The first level: the melting point of the phase change material is 288 K, the width interval of the stepped fins is 2.85 mm, and the length is 0.132 m; The second level: the melting point of the phase change material is 285 K, the width interval of the stepped fins is 2.22 mm, and the length is 0.161 m; The third level: the melting point of the phase change material is 283 K, the width interval of the stepped fins is 2.06 mm, and the length is 0.13 m.
[0013] Beneficial effects: Compared with the prior art, the significant advantages of the present application are that the fin spacing of the stepped fin and the stepped phase change material coupling structure is from large to small, the melting point of the phase change material is from high to low, the matched phase change material melting point is also reduced synchronously when the fluid temperature is reduced, the fluid temperature can be always higher than the melting point of the phase change material, the high latent heat of the material can be fully utilized, the high temperature can be more transmitted out, the temperature regulation of the directed energy weapon is realized, compared with the single-stage heat storage device with unchanged structure and material, the heat transfer temperature difference between the heat fluid and the phase change material is optimized, and the fluid temperature is reduced. The present application significantly improves the heat storage power between the heat fluid and the phase change material, and enhances the temperature regulation ability of the system. BRIEF DESCRIPTION OF DRAWINGS
[0014] Figure 1 It is a three-dimensional diagram of the stepped change of the heat fluid layer and the phase change heat storage layer of the present application; Figure 2 It is a schematic diagram of the overall appearance of the present application; Figure 3 It is a schematic diagram of the heat fluid layer structure of the present application; Figure 4 It is a schematic diagram of the cross section of the heat storage part of the present application; Figure 5 It is a comparison of the FLUENT simulation and the heat network model calculation results of the outlet temperature of the heat fluid under two kinds of heat storage devices; Figure 6 It is a schematic diagram of the temperature change of the inlet heat fluid in the embodiment; Figure 7 In (a) and (b), it is a schematic diagram of the outlet temperature of the heat fluid in the second and third stages of the single-stage heat storage device and the stepped fin and stepped phase change material coupled heat storage device in embodiment one; Figure 8 In (a) and (b), it is a power comparison diagram of the second and third stages of the single-stage heat storage device and the stepped fin and stepped phase change material coupled heat storage device in embodiment one; Figure 9 In (a) and (b), it is a schematic diagram of the outlet temperature of the heat fluid in the second and third stages of the single-stage heat storage device and the optimized stepped fin and stepped phase change material coupled heat storage device mentioned in embodiment two; Figure 10 It is a power comparison diagram of the single-stage heat storage device and the optimized stepped fin and stepped phase change material coupled heat storage device in embodiment two. DETAILED DESCRIPTION
[0015] The technical solutions of the present application will be further described below in combination with the drawings and embodiments.
[0016] As Figures 1-4The illustrated plate-fin phase change heat storage device based on the coupling of stepped fins and stepped phase change materials includes an inlet portion, a heat storage portion, and an outlet portion.
[0017] The heat storage portion internally includes multiple layers of heat fluid layers 1 and phase change heat storage layers 2 arranged alternately and at intervals.
[0018] The heat storage portion is internally divided into multiple layers by horizontal partitions 3, and the heat fluid layers 1 and the phase change heat storage layers 2 are arranged in separate layers.
[0019] The phase change heat storage layer 2 is a coupling structure of stepped fins 201 and stepped phase change materials 202, and the stepped fins 201 and the stepped phase change materials 202 are arranged in at least three stages along the flow direction and are coupled correspondingly at each stage.
[0020] The width interval of the stepped fins 201 decreases step by step along the flow direction, and the melting point of the stepped phase change materials 202 decreases step by step along the flow direction.
[0021] Each stage of the stepped fins 201 is formed by S-shaped connection of straight fins to form multiple phase change material cavities at equal intervals, and the stepped phase change materials 202 are filled in the phase change material cavities, and each phase change material cavity is closed by a 1mm partition at both ends along the flow direction.
[0022] The overall shape is as shown Figure 2 The size is 220 mm x 423 mm x 12.2 mm, and the mass M = 0.7 kg. Three stages are arranged along the flow direction, and the melting points of the phase change materials are 288 K, 285 K, and 283 K along the path, respectively. The intervals of the straight fins at each stage are 2.85 mm, 2.22 mm, and 2.06 mm, respectively, the distribution lengths are 0.132 m, 0.161 m, and 0.13 m, respectively, and the heights are uniformly H pcm = 1 mm; the heat fluid layer 1 adopts a zigzag turbulence structure as shown in Figure 3 to form a heat fluid channel, with an interval d fluid = 1.6 mm and a height H fluid = 2.4 mm.
[0023] Through the coupling of stepped fins and stepped phase change materials, in the initial stage of the system, the heat fluid contacts the phase change material with the highest melting point, triggering melting and heat conduction, effectively reducing the fluid temperature; as the fluid flows along the device, it enters the subsequent section, matching the phase change materials with step-by-step decreasing melting points to adapt to the decrease of the fluid temperature, maintaining the superheat between the fluid and the phase change materials, and ensuring continuous and effective heat conduction.
[0024] In the phase change material filling layer, the volume fraction of phase change material is 64%, which can guarantee the heat storage capacity of the device while reserving space for the skeleton structure, ensuring that the plate-fin skeleton and the spacer plate can stably play the supporting and heat transfer roles. The phase change latent heat of the material is 236 kJ / kg.
[0025] The inlet and outlet parts are both round rectangular cylinders, and the radius of the round part is r =6 mm, and 6063 aluminum alloy material is used, which is selected for its light weight, high strength, good thermal conductivity, easy processability, corrosion resistance, and cost-effectiveness. The fins are also made of 6063 aluminum alloy, which is manufactured by stamping and fixed by welding to ensure the structural stability and heat exchange efficiency of the device.
[0026] The phase change materials are filled into the fin spacing in layers according to the melting point difference. The specific operation is as follows: first, seal the outlet of the device, then inject the low-melting-point phase change material in a molten state, and wait for it to solidify; then, fill the medium-melting-point and high-melting-point phase change materials in the same melting-solidification process. After all three layers of phase change materials are filled and solidified, open the sealed end of the device to complete the entire filling process.
[0027] Example one: this example compares a single-stage heat storage device with a phase change side fin spacing of 3.6 mm and a phase change material melting point of 288 K with a graded fin and graded phase change material coupled heat storage device with a phase change side fin spacing of 3.6 ~ 2.0 mm and a phase change material melting point of 288 ~ 284 K, the specific structure is shown in the figure. The plate-fin skeleton of this case is made of 6063 aluminum alloy by stamping and welding; the thermal physical parameters of the heat fluid and the plate-fin skeleton are shown in Table 1:
[0028] In the early stage of simulation, in order to verify the effectiveness of the established model, the calculation results of the thermal network method are compared and analyzed with the FLUENT simulation results. Two kinds of single-stage uniform heat storage unit structures are selected for verification: the structure parameters of example one are d fluid =1.5 mm, H fluid =1.5 mm, d pcm =3 mm, H pcm =6 mm; in example two d fluid =2.5 mm, H fluid =1.5 mm, d pcm =5 mm, H pcm=10 mm. Under the condition of a constant inlet temperature of 26.85 ℃, the effects of the two structures on the outlet temperature of the hot fluid were investigated. For example... Figure 5 As shown, the FLUENT simulation results are highly consistent with the calculation results of the thermal network model, and the curves basically overlap, indicating that the thermal network model has reliable calculation accuracy and can meet the requirements of subsequent simulations.
[0029] A three-dimensional transient thermal network model of the thermal storage device is established using numerical calculations; such as... Figure 6 The inlet heat flow adopts a periodic unsteady-state inlet condition with a period of 60 seconds and a heat duty cycle of 5:1, with a temperature range of 282 ~ 321 K and a maximum temperature rise of 39 K; the initial temperature of the device is 282 K.
[0030] First, analyze the temperature change of the heat fluid after passing through the heat storage device, such as... Figure 7 (a) and Figure 7 As shown in (b), the results indicate that the fluid temperature in each section of the thermal storage system coupled with the tiered fins and tiered phase change material is lower than that of a single-stage thermal storage device. The final peak outlet temperature decreased from 310 K to 306 K, a reduction of 1.29%; the temperature fluctuation amplitude decreased from 28 K to 24 K, a reduction of 14.29%. This demonstrates that the thermal storage system coupled with the tiered fins and tiered phase change material performs better in suppressing temperature overshoot and can recover to a lower level more quickly after reaching the peak temperature.
[0031] Further analysis of the thermal power of the thermal storage device was conducted under the condition of a constant inlet hot fluid temperature of 321 K. The power comparison between the second and third sections of the device was compared. Figure 8 (a) and Figure 8 As shown in (b), the thermal storage system coupled with the tiered fins and the tiered phase change material can reach the power peak more quickly, and after reaching the peak, the power decay rate is also significantly slower, with the increase in the second and third stages being 34.99% and 36.01%, respectively.
[0032] Example 2: This example compares a single-stage thermal storage system with a phase change side fin spacing of 3.6 mm and a phase change material melting point of 288 K with an optimized thermal storage system featuring a stepped fin spacing of 2.85 ~ 2.06 mm and a stepped phase change material melting point of 288 ~ 283 K. The specific structure is shown in the figure. The specific structure of the optimized thermal storage system with stepped fin spacing and stepped phase change material coupling was obtained by seeking the Pareto optimal solution front using a multi-objective optimization method. The materials and manufacturing method in this example are the same as in Example 1.
[0033] First, the temperature changes of the thermal fluid after passing through the thermal storage device were analyzed. The results show that the fluid temperature in each section of the optimized thermal storage system coupled with the tiered fins and tiered phase change materials is further reduced compared to the single-stage thermal storage device, as shown in 9(a) and Figure 9 (b) shows that the final peak outlet temperature decreased from 310 K to 304 K, a decrease of 1.90%; the temperature fluctuation amplitude decreased from 28 K to 22 K, a decrease of 21.43%. This indicates that the optimized thermal storage system coupled with the tiered fins and tiered phase change material further improves its performance in suppressing temperature overshoot and can recover to a lower level more quickly after the temperature reaches its peak.
[0034] Further analysis of the thermal power of the thermal storage device was conducted under the condition of a constant inlet hot fluid temperature of 321 K. The power at the device's terminal was compared to... Figure 10 As shown, the thermal storage system coupled with the tiered fins and the tiered phase change material can reach the power peak faster, and after reaching the peak, the power decay rate is also significantly slower, with an improvement of 39.65%.
Claims
1. A plate-fin phase change thermal energy storage device based on the coupling of tiered fins and tiered phase change materials, characterized in that: This includes the import portion, the thermal storage portion, and the export portion; The heat storage section includes multiple layers of spaced thermal fluid layer (1) and phase change heat storage layer (2). The phase change thermal storage layer (2) is a coupled structure of stepped fins (201) and stepped phase change material (202). The stepped fins (201) and stepped phase change material (202) are arranged in at least three stages along the flow direction, and are coupled in each stage. The width spacing of the stepped fins (201) decreases step by step with the flow direction, and the melting point of the stepped phase change material (202) decreases step by step with the flow direction.
2. The plate-fin phase change thermal energy storage device based on the coupling of tiered fins and tiered phase change materials according to claim 1, characterized in that: The thermal fluid layer (1) and the phase change thermal storage layer (2) are alternately arranged.
3. The plate-fin phase change thermal energy storage device based on the coupling of tiered fins and tiered phase change materials according to claim 1, characterized in that: The heat storage section is divided into multiple layers by a horizontal partition (3), and the heat fluid layer (1) and the phase change heat storage layer (2) are respectively set in independent partitions.
4. The plate-fin phase change thermal energy storage device based on the coupling of tiered fins and tiered phase change materials according to claim 1, characterized in that: Each of the stepped fins (201) is formed by S-shaped connection of straight fins to form multiple equally spaced phase change material cavities. The stepped phase change material (202) is filled in the phase change material cavities, and each phase change material cavity is closed by a partition at both ends facing the flow direction.
5. The plate-fin phase change thermal storage device based on the coupling of tiered fins and tiered phase change materials according to claim 4, characterized in that: The cascaded phase change material (202) accounts for 64% of the volume of the phase change thermal storage layer (2).
6. The plate-fin phase change thermal energy storage device based on the coupling of tiered fins and tiered phase change materials according to claim 1, characterized in that: The hot fluid layer (1) contains hot fluid channels formed by serrated fins.
7. The plate-fin phase change thermal energy storage device based on the coupling of tiered fins and tiered phase change materials according to claim 1, characterized in that: Both the inlet and outlet sections are rounded rectangular column structures.
8. The plate-fin phase change thermal energy storage device based on the coupling of tiered fins and tiered phase change materials according to claim 1, characterized in that: The stepped fins (201) and stepped phase change material (202) are arranged in three stages along the flow direction; First stage: Phase change material with a melting point of 288 K, stepped fins with a width spacing of 2.85 mm and a length of 0.132 m; Second stage: Phase change material with a melting point of 285 K, stepped fins with a width spacing of 2.22 mm and a length of 0.161 m; The third stage: the phase change material has a melting point of 283 K, and the tiered fins have a width spacing of 2.06 mm and a length of 0.13 m.