Method, device, equipment and medium for suppressing secondary instability of Görtler vortices based on wall heating

Abstract

The present application discloses a method, device, equipment and medium for suppressing the secondary instability of Görtler vortices based on wall heating, which relates to the field of fluid mechanics, and includes: controlling each group of heaters to heat different partitions in the wall of a hypersonic nozzle based on a preset target temperature, and obtaining the partition wall temperatures monitored by each group of temperature sensors during the heating process; determining whether the temperatures of different partitions in the wall meet a preset temperature uniformity condition according to the partition wall temperatures; if not, adjusting each group of heaters based on the preset target temperature and the partition wall temperatures to continue heating the corresponding partitions in the wall, and ending the heating process when the temperatures of different partitions in the wall meet the preset temperature uniformity condition and the temperature of any partition reaches the preset target temperature, so as to make the wall temperature uniform by adjusting the partition heating of the wall, thereby suppressing the secondary instability of Görtler vortices in the boundary layer generated when the fluid flows through the wall.

Description

Technical Field

[0001] The present invention relates to the field of fluid mechanics, and particularly to a method, device, equipment and medium for suppressing the secondary instability of Görtler vortices based on wall heating. Background Art

[0002] Görtler vortices refer to the secondary flow that appears when the boundary layer flows over a curved pipe wall. The boundary layer refers to the part of the fluid immediately adjacent to the pipe wall or other fixed surfaces. For a hypersonic nozzle, the expanding part is a concave surface, that is, the curved wall surface of the hypersonic nozzle; when the fluid flows over the concave surface, due to the imbalance between the centrifugal force and the normal pressure gradient, the centrifugal force is prone to instability, thus forming a pair of coiled streamwise vortices. Such a pair of coiled streamwise vortices often appear in the boundary layer, causing the boundary layer to transition from a laminar state to a turbulent state, that is, causing the transition process of the boundary layer. Specifically, when the Görtler vortices are unstable, due to the formation of a pair of coiled streamwise vortices, there are upward spray and downward sweep regions in the boundary layer. In the upward spray region, the low-momentum fluid close to the wall moves away from the wall and is thrown to the outer edge of the boundary layer, and the boundary layer thickens, forming a low-speed strip region; when the Görtler vortices grow beyond a certain threshold, the low-speed strip region is prone to secondary instability, resulting in the low-speed strip swinging until the strip breaks and turbulence is generated, thereby causing the transition of the hypersonic curved surface boundary layer. Therefore, how to suppress the secondary instability of Görtler vortices is a problem to be solved at present. Summary of the Invention

[0003] In view of this, the purpose of the present application is to provide a method, device, equipment and medium for suppressing the secondary instability of Görtler vortices based on wall heating. By adjusting the partition heating of the wall surface to make the wall surface temperature uniform, the control of Görtler vortices and the secondary instability process in the hypersonic curved surface boundary layer is realized, thereby delaying the transition process of the boundary layer, so that the boundary layer can be maintained in a laminar state as much as possible. At the same time, combined with the suppression of the secondary instability of Görtler vortices, the wind tunnel inflow noise can be reduced. The specific solutions are as follows:

[0004] In a first aspect, the present application provides a method for suppressing the secondary instability of Görtler vortices based on wall heating, which is applied to a temperature controller and includes:

[0005] Based on a preset target temperature, control each group of heaters to heat different partitions of the wall surface of the hypersonic nozzle, and during the heating process, obtain the partition wall surface temperatures obtained by each group of temperature sensors monitoring the different partitions of the wall surface; wherein, different partitions of the wall surface correspond to different groups of the heaters and different groups of the temperature sensors;

[0006] Determine whether the temperatures of different partitions in the wall meet the preset temperature uniformity condition according to the partition wall temperatures;

[0007] If not, adjust each group of the heaters based on the preset target temperature and the partition wall temperatures, and control the adjusted heaters to continue heating the corresponding partitions in the wall, so as to end the heating process when the temperatures of different partitions in the wall meet the preset temperature uniformity condition and the temperature of any partition in the wall reaches the preset target temperature, so as to suppress the secondary instability of the Görtler vortices in the boundary layer generated when the fluid flows through the wall.

[0008] Optionally, the obtaining the partition wall temperatures obtained by each group of temperature sensors for temperature monitoring of different partitions in the wall includes:

[0009] Obtain the current monitoring temperature obtained by each temperature sensor in any group of the temperature sensors for temperature monitoring of the same partition in the wall, and determine the partition wall temperature of any group of the temperature sensors based on the average value of the current monitoring temperatures.

[0010] Optionally, the preset temperature uniformity condition includes that the temperature difference between any two partitions in the wall is not greater than the preset temperature difference.

[0011] Optionally, the method for suppressing the secondary instability of Görtler vortices based on wall heating further includes:

[0012] When the temperatures of different partitions in the wall meet the preset temperature uniformity condition and the temperatures of different partitions in the wall do not reach the preset target temperature, continue to execute the step of controlling each group of heaters to heat different partitions in the wall of the hypersonic nozzle based on the preset target temperature.

[0013] Optionally, the method for suppressing the secondary instability of Görtler vortices based on wall heating further includes:

[0014] After turning on the main power switch to supply power to the temperature controller, obtain a temperature setting command through a preset interface, and set the corresponding preset target temperature for the temperature controller based on the temperature setting command;

[0015] Correspondingly, the controlling each group of heaters to heat different partitions in the wall of the hypersonic nozzle based on the preset target temperature includes:

[0016] Control the sub-power switches of each group of the heaters to be turned on based on the preset target temperature, so that each group of the heaters heats different partitions in the wall of the hypersonic nozzle.

[0017] Optionally, adjusting each group of the heaters based on the preset target temperature and the partition wall temperature, and controlling the adjusted heaters to continue heating the corresponding partitions in the wall, includes:

[0018] Determining target partitions in different partitions of the wall whose temperatures reach the preset target temperature, controlling the sub-power switches of the first target group of heaters corresponding to the target partitions to turn off, and adjusting the heating power of the second target group of heaters corresponding to other partitions based on the partition wall temperature; the other partitions are the remaining partitions in different partitions of the wall except the target partitions;

[0019] Controlling the second target group of heaters to continue heating the corresponding partitions in the wall based on the adjusted heating power.

[0020] In a second aspect, the present application provides a device for suppressing the secondary instability of Görtler vortices based on wall heating, which is applied to a temperature controller and includes:

[0021] A wall temperature acquisition module, configured to control each group of heaters to heat different partitions in the wall of a hypersonic nozzle based on a preset target temperature, and during the heating process, acquire the partition wall temperature obtained by each group of temperature sensors monitoring the temperature of different partitions in the wall; wherein, different partitions in the wall correspond to different groups of the heaters and different groups of the temperature sensors;

[0022] A temperature uniformity determination module, configured to determine whether the temperatures of different partitions in the wall meet a preset temperature uniformity condition according to the partition wall temperature;

[0023] A wall partition heating module, configured to, if not satisfied, adjust each group of the heaters based on the preset target temperature and the partition wall temperature, and control the adjusted heaters to continue heating the corresponding partitions in the wall, so as to end the heating process when the temperatures of different partitions in the wall meet the preset temperature uniformity condition and the temperature of any partition in the wall reaches the preset target temperature, so as to suppress the secondary instability of Görtler vortices in the boundary layer generated by the fluid on the wall.

[0024] Optionally, the wall temperature acquisition module includes:

[0025] A temperature determination unit, configured to acquire the current monitoring temperature obtained by each temperature sensor in any group of the temperature sensors monitoring the same partition in the wall, and determine the partition wall temperature of any group of the temperature sensors based on the average value of the current monitoring temperatures.

[0026] In a third aspect, the present application provides an electronic device, including:

[0027] a memory for storing a computer program;

[0028] a processor for executing the computer program to implement the aforementioned method for suppressing the secondary instability of Görtler vortices based on wall heating.

[0029] In a fourth aspect, the present application provides a computer-readable storage medium for storing a computer program, wherein when the computer program is executed by a processor, the aforementioned method for suppressing the secondary instability of Görtler vortices based on wall heating is implemented.

[0030] In the present application, based on a preset target temperature, each group of heaters is controlled to heat different partitions in the wall of the hypersonic nozzle, and during the heating process, the partition wall temperatures obtained by each group of temperature sensors monitoring the temperatures of different partitions in the wall are acquired; wherein, different partitions in the wall correspond to different groups of the heaters and different groups of the temperature sensors; it is determined whether the temperatures of different partitions in the wall meet a preset temperature uniformity condition according to the partition wall temperatures; if not, each group of the heaters is adjusted based on the preset target temperature and the partition wall temperatures, and the adjusted heaters are controlled to continue heating the corresponding partitions in the wall, so as to end the heating process when the temperatures of different partitions in the wall meet the preset temperature uniformity condition and the temperature of any partition in the wall reaches the preset target temperature, so as to suppress the secondary instability of Görtler vortices in the boundary layer generated when a fluid flows through the wall. As can be seen from the above, in the present application, by heating different partitions in the wall and determining whether the temperatures of different partitions in the wall meet the preset temperature uniformity condition according to the partition wall temperatures, if not, each group of heaters is adjusted, and the adjusted heaters are controlled to continue heating the corresponding partitions in the wall, so as to realize the heating adjustment of the temperatures of different partitions in the wall, thereby ensuring uniform distribution of the wall temperature, reducing the temperature difference between different partitions in the wall, further realizing the suppression effect on Görtler vortices and the secondary instability process in the hypersonic curved boundary layer, thereby delaying the position of the hypersonic curved boundary layer transition and making the boundary layer maintain a laminar state as much as possible. At the same time, combined with the suppression of the secondary instability of Görtler vortices, the wind tunnel inflow noise can be reduced. Description of the Drawings

[0031] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings described below are only the embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0032] Figure 1 It is a flowchart of a method for suppressing the secondary instability of Görtler vortices based on wall heating disclosed in the present application;

[0033] Figure 2 It is a front view of the boundary layer under different wall temperature conditions disclosed in the present application;

[0034] Figure 3 It is a schematic diagram of the change of the wall friction coefficient along the flow direction under different wall temperature conditions disclosed in the present application;

[0035] Figure 4 It is a schematic diagram of the change of the secondary instability mode perturbation rate of Görtler vortices along the frequency under different wall temperatures and different flow direction positions disclosed in the present application;

[0036] Figure 5 It is a schematic diagram of a curved surface model disclosed in the present application;

[0037] Figure 6 It is a schematic diagram of the device structure for suppressing the secondary instability of Görtler vortices based on wall heating disclosed in the present application;

[0038] Figure 7 It is a structural diagram of an electronic device disclosed in the present application. Detailed implementation manners

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0040] When the Görtler vortex is unstable, due to the formation of streamwise vortices that pair and roll up, there are regions of upward ejection and downward sweep in the boundary layer. In the upward ejection region, the low-momentum fluid near the wall moves away from the wall and is thrown towards the outer edge of the boundary layer, causing the boundary layer to thicken and form low-speed streak regions. When the Görtler vortex grows beyond a certain threshold, the low-speed streak regions are prone to secondary instability, resulting in the oscillation of the low-speed streaks until the streaks break and turbulence is generated, thus triggering the transition of the hypersonic curved boundary layer. For this reason, the present application provides a method for suppressing the secondary instability of Görtler vortices based on wall heating. By adjusting the partition heating of the wall to make the wall temperature uniform, the control of Görtler vortices and the secondary instability process in the hypersonic curved boundary layer is achieved, thereby delaying the transition process of the boundary layer, so that the boundary layer is maintained in the laminar state as much as possible. At the same time, by combining the suppression of the secondary instability of Görtler vortices, the wind tunnel inflow noise can be reduced.

[0041] See Figure 1 As shown, an embodiment of the present application discloses a method for suppressing the secondary instability of Görtler vortices based on wall heating, which is applied to a temperature controller and includes:

[0042] Step S11: Based on a preset target temperature, control each group of heaters to heat different partitions of the wall of the hypersonic nozzle, and during the heating process, obtain the partition wall temperatures obtained by each group of temperature sensors monitoring the temperatures of different partitions of the wall; wherein, different partitions of the wall correspond to different groups of the heaters and different groups of the temperature sensors.

[0043] In this embodiment, the temperature controller controls each group of heaters to heat different partitions of the wall of the hypersonic nozzle based on a preset target temperature, and at the same time monitors the temperatures of different partitions of the wall through each group of temperature sensors to obtain the partition wall temperatures corresponding to different partitions of the wall respectively, and then transmits the partition wall temperatures to the temperature controller.

[0044] Before controlling each group of heaters to heat different partitions of the wall of the hypersonic nozzle based on a preset target temperature, power on the temperature controller by turning on the main power switch, and based on the preset interface after power-on, obtain a temperature setting command, and set a corresponding preset target temperature for the temperature controller based on the temperature setting command.

[0045] Further, after the temperature controller sets a corresponding preset target temperature for itself based on the temperature setting command, it can control the sub-power switches of each group of heaters to turn on based on the above preset target temperature, so that each group of heaters heats different partitions in the wall surface of the hypersonic nozzle. It can be understood that one partition in the wall surface corresponds to a group of heaters and a group of temperature sensors, and each group of heaters can be controlled by an independent sub-power switch. It should be noted that turning on the main power switch not only powers the temperature controller, but also powers the temperature sensors, and also powers the heaters after the sub-power switches are turned on.

[0046] For the preset interface on the temperature controller for obtaining the temperature setting command, in a specific implementation manner, the user directly sets the target temperature through the temperature controller to issue a corresponding temperature setting command; correspondingly, the preset interface on the temperature controller will obtain the temperature setting command issued by the user and parse the temperature setting command to set a corresponding target temperature for itself according to the parsed temperature information, so that the temperature controller controls each group of heaters to perform partition heating adjustment on the wall surface of the hypersonic nozzle based on the target temperature.

[0047] For the preset interface on the temperature controller for obtaining the temperature setting command, in another specific implementation manner, first, a mobile device, such as a smartphone, a tablet computer, etc., is wirelessly paired and connected with the temperature controller. After the mobile device is successfully connected to the temperature controller, the user inputs the target temperature in the application on the mobile device, so that the mobile device sends the temperature setting command constructed based on the target temperature to the temperature controller through the wireless connection. Correspondingly, the temperature controller receives the temperature setting command from the mobile device through its own wireless interface and parses the temperature setting command to set a corresponding target temperature for itself according to the parsed temperature information, so that the temperature controller controls each group of heaters to perform partition heating adjustment on the wall surface of the hypersonic nozzle based on the target temperature. Among them, the wireless interface includes Bluetooth, Wi-Fi (Wireless Fidelity, mobile hotspot), etc.

[0048] It can be understood that, in order to make the wall surface heated evenly, the wall surface can be heated in zones. Specifically, first, the wall surface is divided into several independent zones, namely heating zones, according to the structural characteristics of the wall surface, temperature control requirements, etc. These zones can be regular, such as annular, rectangular, etc., or irregular, specifically depending on the shape and size of the nozzle. For each zone, a set of heaters and a set of temperature sensors are configured. Among them, the heaters are used to heat the wall surface, including resistance heaters, electromagnetic induction heaters or other types of heating elements. A set of heaters includes at least one heater, and the number, layout and power of the heaters should be determined according to the zone area, heat demand and preset target temperature to ensure that each zone can be heated evenly and effectively. For example, for areas with a larger wall thickness, the number of heaters is increased, and for areas with a smaller wall thickness, the number of heaters is reduced. The temperature sensors are used to monitor the wall surface temperature in real time to obtain the zone wall surface temperature. Correspondingly, a set of temperature sensors includes at least one temperature sensor. For a wall surface with a relatively long flow direction distribution, multiple temperature sensors can be arranged along the flow direction to monitor the wall surface temperature during the heating process. For example, for a curved wall surface such as a nozzle, the temperature may be unevenly distributed on the upper and lower sides, so multiple temperature sensors can be arranged on the upper and lower sides to monitor the wall surface temperature on the upper and lower sides of the nozzle in real time. By controlling the wall surface in zones, it is ensured that the wall surface temperature distribution is uniform.

[0049] Furthermore, since one zone in the wall surface corresponds to a set of temperature sensors, and a set of temperature sensors includes at least one temperature sensor, that is, one zone in the wall surface may correspond to multiple temperature values collected by multiple temperature sensors. In order to obtain the zone wall surface temperature of each zone in the wall surface, the temperature controller needs to obtain the current monitoring temperature obtained by each temperature sensor in any set of temperature sensors for temperature monitoring of the same zone in the wall surface, and determine the zone wall surface temperature of any set of temperature sensors based on the average value of the current monitoring temperatures, so that the zone wall surface temperature of each zone in the wall surface can be obtained.

[0050] It can be understood that for each zone in the wall surface, first, the readings of multiple temperature sensors in a set of temperature sensors corresponding to each zone need to be obtained, and the zone wall surface temperature of the corresponding zone is determined based on the average value of the readings of multiple temperature sensors in a set of temperature sensors. It should be noted that since the average value represents the overall temperature estimation of the corresponding zone by the set of temperature sensors, the average value can be used as the zone wall surface temperature of the corresponding zone.

[0051] Step S12, determine whether the temperatures of different zones in the wall surface meet the preset temperature uniformity condition according to the zone wall surface temperature.

[0052] In this embodiment, after obtaining the partition wall temperatures of different partitions in the wall surface, it is necessary to determine whether the temperatures of different partitions in the wall surface meet the preset temperature uniformity condition according to the partition wall temperatures. Among them, the preset temperature uniformity condition includes that the temperature difference between any two partitions in the wall surface is not greater than the preset temperature difference. For the preset temperature difference, it can be set according to the actual suppression effect on the secondary instability of Görtler vortices. Among them, if a better suppression effect is desired, the preset temperature difference can be set smaller.

[0053] It can be understood that in order to determine whether the entire wall surface meets the preset temperature uniformity condition, for each partition in the wall surface, it can be compared with all other partitions. Specifically, calculate the temperature difference between any two partitions in the wall surface, and compare the calculated temperature difference with the preset temperature difference. If the temperature difference is not greater than the preset temperature difference, it is considered that the temperatures of these two partitions meet the preset temperature uniformity condition. If the temperature difference is greater than the preset temperature difference, it is considered that the temperatures of these two partitions do not meet the preset temperature uniformity condition. If the temperature difference between any two partitions in the wall surface is not greater than the preset temperature difference, it is determined that the wall surface meets the preset temperature uniformity condition. If the temperature difference between a certain two partitions in the wall surface is greater than the preset temperature difference, it is determined that the wall surface does not meet the preset temperature uniformity condition.

[0054] Step S13: If not satisfied, adjust each group of heaters based on the preset target temperature and the partition wall temperature, and control the adjusted heaters to continue heating the corresponding partitions in the wall surface, so as to end the heating process when the temperatures of different partitions in the wall surface meet the preset temperature uniformity condition and the temperature of any partition in the wall surface reaches the preset target temperature, so as to suppress the secondary instability of Görtler vortices in the boundary layer generated when the fluid flows through the wall surface.

[0055] In this embodiment, if the temperatures of different partitions in the wall surface do not meet the preset temperature uniformity condition, adjust each group of heaters based on the preset target temperature and the partition wall temperature of each partition, and control the adjusted heaters to continue heating the corresponding partitions in the wall surface. The specific steps include: determining the target partition whose temperature reaches the preset target temperature from different partitions in the wall surface, and controlling the sub-power switch of the first target group of heaters corresponding to the target partition to be turned off, and adjusting the heating power of the second target group of heaters corresponding to other partitions based on the partition wall temperature; where other partitions are the remaining partitions except the target partition among different partitions in the wall surface; after adjusting the heating power of the second target group of heaters, control the second target group of heaters to continue heating the corresponding partitions in the wall surface based on the adjusted heating power.

[0056] It can be understood that if the wall surface does not meet the preset temperature uniformity condition, it means that the temperature difference between some partitions in the wall surface is relatively large at this time. In order to make the overall temperature of the wall surface uniform, it is necessary to increase the heating power of the heater corresponding to the partition with a lower temperature, and / or reduce the heating power of the heater corresponding to the partition with a higher temperature. It is also possible to turn off the heater corresponding to the partition whose temperature has reached the preset target temperature. Specifically, first, it is judged whether there is a target partition in different partitions of the wall surface whose temperature has reached the preset target temperature. If so, it means that the target partition no longer needs to be heated continuously. At this time, the sub-power switch of the first target group of heaters corresponding to the target partition can be controlled to be turned off to avoid overheating. Further, for the partition in the wall surface whose temperature has not reached the preset target temperature, the heating power of the second target group of heaters corresponding to this partition can be adjusted to continue heating the partition whose temperature has not reached the preset target temperature.

[0057] It should be noted that for the partition whose temperature is significantly lower than the preset target temperature, or the partition whose temperature is significantly lower than the temperature of other partitions, the heating power of the heater corresponding to this partition can be increased significantly; for the partition whose temperature is close to but has not reached the preset target temperature, or the partition whose temperature is slightly lower than the temperature of other partitions, the heating power of the heater corresponding to this partition can be increased moderately or the current power can be maintained, specifically depending on the temperature rising trend. For the partition whose temperature is lower than the preset target temperature but significantly higher than the temperature of other partitions, the heating power of the heater corresponding to this partition can be reduced moderately to ensure that the wall surface can maintain temperature uniformity as much as possible during the wall surface heating process.

[0058] Further, when the temperatures of different partitions in the wall surface meet the preset temperature uniformity condition and the temperatures of different partitions in the wall surface have not reached the preset target temperature, continue to execute the step in S11 of controlling each group of heaters to heat different partitions in the wall surface of the hypersonic nozzle based on the preset target temperature. Specifically, if the temperatures of different partitions in the wall surface meet the preset temperature uniformity condition but the temperatures of all partitions in the wall surface have not reached the preset target temperature, it is necessary to continue the heating process to ensure that the wall surface temperature is uniform and continuously approaches and until it reaches the preset target temperature. It can be understood that the temperature sensor monitors the temperature of each partition in the wall surface in real time. When the temperature of any partition in the wall surface reaches the preset target temperature, the heater corresponding to the partition whose temperature reaches the preset target temperature is controlled to be turned off. If the temperatures of different partitions in the wall surface meet the preset temperature uniformity condition and at least one partition in the wall surface has a temperature reaching the preset target temperature, the heating process ends.

[0059] As can be seen from the above, in this application, the wall surface is partitioned, and an independent set of heaters and a set of temperature sensors are provided for each partition. The heaters are used to heat different partitions of the wall surface, and the temperature sensors are used to monitor different partitions of the wall surface in real time to obtain the partition wall surface temperature of each partition in the wall surface. Further, the temperature controller determines whether the temperatures of different partitions in the wall surface meet the preset temperature uniformity condition based on the partition wall surface temperature. If not, it adjusts the heating power of each group of heaters and controls the heaters to continue heating the corresponding partitions in the wall surface based on the adjusted heating power, so as to reduce the temperature difference between different partitions in the wall surface, thereby ensuring uniform distribution of the wall surface temperature, further achieving the suppression effect on the Görtler vortices and the secondary instability process in the hypersonic curved boundary layer, thereby delaying the transition position of the hypersonic curved boundary layer and keeping the boundary layer in the laminar state as much as possible. At the same time, combined with the suppression of the secondary instability of the Görtler vortices, the wind tunnel inflow noise can be reduced.

[0060] Take Figure 2 the wall heating device shown in the figure for implementing the method for suppressing the secondary instability of Görtler vortices based on wall heating in this application as an example, and elaborate in detail on the method for suppressing the secondary instability of Görtler vortices based on wall heating in this application. Among them, Figure 2 the wall heating device shown in the figure includes a temperature controller, a temperature sensor, and a heater, and, Figure 2 the total length of the wall heating device shown in the figure is 250 mm, the length of the curved surface part is 200 mm, and the radius of curvature is 800 mm. The specific scheme is as follows:

[0061] First, control the main power switch to turn on to supply power to the temperature controller, the temperature sensor, and the heater after turning on the sub-power switch. The temperature controller obtains the temperature setting command issued by the user through a preset interface and sets the corresponding target temperature for itself based on the temperature setting command, so that the temperature controller controls each group of heaters to perform partition heating adjustment on the wall surface of the hypersonic nozzle based on the target temperature.

[0062] Further, the temperature controller obtains the current monitoring temperature obtained by each temperature sensor in any group of temperature sensors for monitoring the same partition in the wall surface, and determines the partition wall surface temperature of any group of temperature sensors based on the average value of each current monitoring temperature, so as to obtain the partition wall surface temperature of each partition in the wall surface.

[0063] Next, the temperature controller determines whether the temperatures of different zones in the wall meet the preset temperature uniformity condition according to the above-mentioned partition wall temperatures. If the temperatures of different zones in the wall do not meet the preset temperature uniformity condition, each group of heaters is adjusted based on the above-mentioned target temperature and the partition wall temperatures of each zone, and the adjusted heaters are controlled to continue heating the corresponding zones in the wall. Among them, when the temperature of any zone in the wall reaches the target temperature, the temperature controller controls the heater corresponding to the zone with the temperature reaching the target temperature to turn off. If the temperatures of different zones in the wall meet the preset temperature uniformity condition and the temperature of at least one zone in the wall reaches the target temperature, the heating process is ended to suppress the secondary instability of the Görtler vortices in the boundary layer generated when the fluid flows through the wall.

[0064] For example, as Figure 3 shown, the front view of the boundary layer under different wall temperature conditions; among them, Figure 3 in (a) corresponds to the front view of the boundary layer when the wall temperature is 300K, Figure 3 in (b) corresponds to the front view of the boundary layer when the wall temperature is 400K, Figure 3 in (c) corresponds to the front view of the boundary layer when the wall temperature is 500K. The horizontal axis in the figure represents the flow direction position, and the vertical axis represents the vertical position. It can be seen that as the wall temperature continuously increases, the position where the fine structure begins to appear at the outer edge of the boundary layer is closer to the downstream, that is, heating the wall can make the transition position of the boundary layer move backward continuously.

[0065] Figure 4 shows the variation of the wall friction coefficient along the flow direction position under different wall temperature conditions; among them, the horizontal axis in the figure represents the flow direction position, and the vertical axis represents the friction coefficient. It can be seen that as the wall temperature increases, the flow direction position corresponding to when the wall friction coefficient begins to deviate from the laminar state moves significantly downstream, and the flow direction position corresponding to when the wall friction coefficient reaches the maximum value also moves downstream. At the same time, after heating the wall, the friction coefficient corresponding to the boundary layer after transition is much smaller than the friction coefficient corresponding to the boundary layer after transition when the wall is not heated. Therefore, heating the wall can delay the transition process of the hypersonic surface boundary layer.

[0066] Figure 5 shows the variation of the perturbation rate of the Görtler vortex secondary instability mode with frequency under different wall temperatures and different flow direction position conditions; among them, Figure 5 in (a), Figure 5 in (c), and Figure 5 in (e) are the variations of the perturbation rate of the Görtler vortex secondary instability mode with frequency at different wall temperatures when the flow direction position is 180mm; Figure 5 in (b), Figure 5 in (d), Figure 5Among them, (f) shows the variation of the perturbation rate of the secondary instability mode of Görtler vortices with frequency at different wall temperatures when the flow direction position is 200 mm. Among them, the horizontal axis in the figure is the frequency, and the vertical axis is the perturbation rate. The curve corresponding to perturbation 1 is the curve of the variation of the perturbation rate of the secondary instability mode of Görtler vortices with frequency improved by the method disclosed in this application, and the curve corresponding to perturbation 2 is the curve of the variation of the perturbation rate of the secondary instability mode of Görtler vortices with frequency without being improved by the method disclosed in this application. It can be seen that at the same flow direction position, as the wall temperature continuously increases, the maximum perturbation rate of the secondary instability mode of Görtler vortices continuously decreases, and the frequency range covered by the perturbation curve also decreases accordingly. Therefore, through Figure 5 It can be found that by heating the wall in zones to ensure a uniform wall temperature distribution, the growth of the secondary instability mode of Görtler vortices can be significantly inhibited, thereby achieving the purpose of delaying the transition of the hypersonic curved surface boundary layer.

[0067] As can be seen from the above, this application divides the wall into zones and sets a separate set of heaters and a set of temperature sensors for each zone. The heaters are used to heat different zones of the wall, and the temperature sensors are used to monitor different zones of the wall in real time to obtain the partition wall temperature of each zone in the wall. Further, the temperature controller determines whether the temperatures of different zones in the wall meet the preset temperature uniformity condition based on the partition wall temperature. If not, it adjusts the heating power of each group of heaters and controls the heaters to continue heating the corresponding zones in the wall based on the adjusted heating power to reduce the temperature difference between different zones in the wall, thereby ensuring a uniform wall temperature distribution, further achieving the inhibitory effect on Görtler vortices and the secondary instability process in the hypersonic curved surface boundary layer, thereby delaying the position of the transition of the hypersonic curved surface boundary layer, making the boundary layer maintain a laminar state as much as possible. At the same time, combined with the inhibition of the secondary instability of Görtler vortices, the oncoming flow noise of the wind tunnel can be reduced.

[0068] See Figure 6 As shown, the embodiment of this application also discloses a device for suppressing the secondary instability of Görtler vortices based on wall heating, which is applied to a temperature controller and includes:

[0069] A wall temperature acquisition module 11, configured to control each group of heaters to heat different zones of the wall of the hypersonic nozzle based on a preset target temperature, and during the heating process, acquire the partition wall temperature obtained by each group of temperature sensors monitoring different zones of the wall; wherein, different zones in the wall correspond to different groups of the heaters and different groups of the temperature sensors;

[0070] A temperature uniformity determination module 12, configured to determine whether the temperatures of different partitions in the wall meet a preset temperature uniformity condition according to the partition wall temperatures;

[0071] A wall partition heating module 13, configured to, if not satisfied, adjust each group of the heaters based on the preset target temperature and the partition wall temperatures, and control the adjusted heaters to continue heating the corresponding partitions in the wall, so as to end the heating process when the temperatures of different partitions in the wall meet the preset temperature uniformity condition and the temperature of any partition in the wall reaches the preset target temperature, so as to suppress the secondary instability of Görtler vortices in the boundary layer generated by the fluid on the wall.

[0072] As can be seen from the above, in this application, the wall is partitioned, and an independent group of heaters and a group of temperature sensors are set for each partition. The heaters are used to heat different partitions in the wall, and the temperature sensors are used to monitor different partitions in the wall in real time to obtain the partition wall temperatures of each partition in the wall. Further, the temperature controller determines whether the temperatures of different partitions in the wall meet the preset temperature uniformity condition based on the partition wall temperatures. If not, it adjusts the heating power of each group of heaters, and controls the heaters to continue heating the corresponding partitions in the wall based on the adjusted heating power, so as to reduce the temperature difference between different partitions in the wall, thereby ensuring uniform distribution of the wall temperature, further achieving the suppression effect on Görtler vortices and the secondary instability process in the hypersonic curved surface boundary layer, thereby delaying the position of the hypersonic curved surface boundary layer transition, making the boundary layer maintain a laminar state as much as possible, and at the same time, combining the suppression of the secondary instability of Görtler vortices, the wind tunnel oncoming flow noise can be reduced.

[0073] In some specific embodiments, the wall temperature acquisition module 11 may specifically include:

[0074] A temperature determination unit, configured to obtain the current monitored temperatures obtained by each of the temperature sensors in any group of the temperature sensors for temperature monitoring of the same partition in the wall, and determine the partition wall temperature of any group of the temperature sensors based on the average value of the current monitored temperatures.

[0075] In some specific embodiments, the preset temperature uniformity condition includes that the temperature difference between any two partitions in the wall is not greater than a preset temperature difference.

[0076] In some specific embodiments, the device for suppressing the secondary instability of Görtler vortices based on wall heating further includes:

[0077] A first heating unit, configured to continue to execute the step of controlling each group of heaters to heat different partitions of the wall surface of the hypersonic nozzle based on a preset target temperature when the temperatures of different partitions in the wall surface meet the preset temperature uniformity condition and the temperatures of different partitions in the wall surface do not reach the preset target temperature.

[0078] In some specific embodiments, the device for suppressing the secondary instability of Görtler vortices based on wall heating further includes:

[0079] A command acquisition unit, configured to acquire a temperature setting command through a preset interface after turning on the main power switch to supply power to the temperature controller;

[0080] A temperature setting unit, configured to set the corresponding preset target temperature for the temperature controller based on the temperature setting command;

[0081] Correspondingly, the wall surface temperature acquisition module 11 includes:

[0082] A second heating unit, configured to control the sub-power switches of each group of the heaters to be turned on based on the preset target temperature, so that each group of the heaters heats different partitions of the wall surface of the hypersonic nozzle.

[0083] In some specific embodiments, the wall surface partition heating module 13 may specifically include:

[0084] A power switch closing unit, configured to determine a target partition in which the temperature reaches the preset target temperature from different partitions of the wall surface, and control the sub-power switch of the first target group of heaters corresponding to the target partition to be turned off;

[0085] A power adjustment unit, configured to adjust the heating power of the second target group of heaters corresponding to other partitions based on the partition wall surface temperature; the other partitions are the remaining partitions except the target partition among different partitions of the wall surface;

[0086] A third heating unit, configured to control the second target group of heaters to continue to heat the corresponding partitions on the wall surface based on the adjusted heating power.

[0087] Furthermore, an embodiment of the present application also discloses an electronic device, Figure 7It is a structural diagram of an electronic device 20 shown according to an exemplary embodiment. The content in the figure should not be regarded as any limitation on the scope of use of this application. The electronic device 20 may specifically include: at least one processor 21, at least one memory 22, a power supply 23, a communication interface 24, an input / output interface 25, and a communication bus 26. Among them, the memory 22 is used to store a computer program, and the computer program is loaded and executed by the processor 21 to implement the relevant steps in the method for suppressing the secondary instability of Görtler vortices based on wall heating disclosed in any of the foregoing embodiments. Additionally, the electronic device 20 in this embodiment may specifically be an electronic computer.

[0088] In this embodiment, the power supply 23 is used to provide operating voltage for each hardware device on the electronic device 20; the communication interface 24 can create a data transmission channel between the electronic device 20 and external devices, and the communication protocol it follows can be any communication protocol applicable to the technical solution of this application, and no specific limitation is imposed on it here; the input / output interface 25 is used to obtain external input data or output data to the outside, and its specific interface type can be selected according to specific application needs, and no specific limitation is made here.

[0089] In addition, the memory 22, as a carrier for resource storage, can be a read-only memory, a random access memory, a disk, or an optical disc, etc. The resources stored thereon can include an operating system 221, a computer program 222, etc., and the storage method can be temporary storage or permanent storage.

[0090] Among them, the operating system 221 is used to manage and control each hardware device and the computer program 222 on the electronic device 20, and it can be Windows Server, Netware, Unix, Linux, etc. In addition to the computer program that can be used to complete the method for suppressing the secondary instability of Görtler vortices based on wall heating executed by the electronic device 20 disclosed in any of the foregoing embodiments, the computer program 222 may further include computer programs that can be used to complete other specific tasks.

[0091] Furthermore, this application also discloses a computer-readable storage medium for storing a computer program; wherein, when the computer program is executed by a processor, it implements the method for suppressing the secondary instability of Görtler vortices based on wall heating disclosed above. For the specific steps of this method, reference can be made to the corresponding content disclosed in the foregoing embodiments, and details will not be repeated here.

[0092] In this specification, the various embodiments are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For the relevant parts, reference can be made to the description in the method section.

[0093] Those skilled in the art can further realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. To clearly illustrate the interchangeability of hardware and software, the components and steps of the examples have been generally described according to their functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0094] The steps of the methods or algorithms described in combination with the embodiments disclosed herein can be directly implemented by hardware, software modules executed by a processor, or a combination of the two. The software modules can be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium well-known in the technical field.

[0095] Finally, it should also be noted that in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0096] The technical solutions provided in this application have been introduced in detail above. Specific examples are used herein to elaborate on the principles and implementation manners of this application. The description of the above embodiments is only used to help understand the method and its core idea of this application; at the same time, for those of ordinary skill in the art, according to the idea of this application, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to this application.

Claims

1. A method for suppressing Görtler vortex secondary instability based on wall heating, characterized in that: Applications in temperature controllers, including: Based on the preset target temperature, each group of heaters is controlled to heat different partitions in the wall surface of the hypersonic nozzle, and during the heating process, the partition wall temperature obtained after each group of temperature sensors monitors the temperature of different partitions in the wall surface; wherein different partitions in the wall surface correspond to different groups of heaters and different groups of temperature sensors; Determining whether the temperatures of different partitions in the wall surface meet a preset temperature uniformity condition according to the partition wall surface temperature; If not satisfied, each group of the heaters is adjusted based on the preset target temperature and the partition wall temperature, and the adjusted heaters are controlled to continue heating the corresponding partitions in the wall, so that when the temperatures of different partitions in the wall meet the preset temperature uniformity condition and the temperature of any partition in the wall reaches the preset target temperature, the heating process is terminated to suppress the secondary instability of the Görtler vortex in the boundary layer generated when the fluid flows through the wall.

2. The method for suppressing Görtler vortex secondary instability based on wall heating according to claim 1 is characterized in that: The obtaining of the partition wall surface temperatures obtained after each group of temperature sensors monitors the temperatures of different partitions in the wall surface comprises: The current monitored temperature obtained by each temperature sensor in any group of the temperature sensors after monitoring the temperature of the same partition in the wall is obtained, and the partition wall temperature of any group of the temperature sensors is determined based on the average value of each current monitored temperature.

3. The method for suppressing Görtler vortex secondary instability based on wall heating according to claim 1, characterized in that: The preset temperature uniformity condition includes that the temperature difference between any two partitions in the wall surface is not greater than the preset temperature difference.

4. The method for suppressing Görtler vortex secondary instability based on wall heating according to claim 1, characterized in that: Also includes: When the temperatures of different partitions in the wall surface satisfy the preset temperature uniformity condition and the temperatures of different partitions in the wall surface do not reach the preset target temperature, the step of controlling each group of heaters to heat different partitions in the wall surface of the hypersonic nozzle based on the preset target temperature continues to be performed.

5. The method for suppressing Görtler vortex secondary instability based on wall heating according to any one of claims 1 to 4, characterized in that: Before controlling each group of heaters to heat different partitions on the wall of the hypersonic nozzle based on the preset target temperature, the method further includes: After turning on the main power switch to supply power to the temperature controller, obtaining a temperature setting command through a preset interface, and setting a corresponding preset target temperature for the temperature controller based on the temperature setting command; Accordingly, the method of controlling each group of heaters to heat different partitions on the wall of the hypersonic nozzle based on the preset target temperature includes: Based on the preset target temperature, the sub-power switches of each group of the heaters are controlled to turn on, so that each group of the heaters heats different partitions in the wall of the hypersonic nozzle.

6. The method for suppressing Görtler vortex secondary instability based on wall heating according to claim 5 is characterized in that: The step of adjusting each group of the heaters based on the preset target temperature and the partition wall temperature, and controlling the adjusted heaters to continue heating the corresponding partitions in the wall surface, comprises: Determine a target zone whose temperature reaches the preset target temperature from different zones in the wall surface, control the sub-power switch of the first target group heater corresponding to the target zone to turn off, and adjust the heating power of the second target group heater corresponding to other zones based on the zone wall surface temperature; the other zones are the remaining zones among the different zones in the wall surface except the target zone; The second target group of heaters is controlled to continue heating corresponding subareas in the wall surface based on the adjusted heating power.

7. A device for suppressing secondary instability of Görtler vortex based on wall heating, characterized in that: Applications in temperature controllers, including: A wall surface temperature acquisition module, used to control each group of heaters to heat different partitions in the wall surface of the hypersonic nozzle based on a preset target temperature, and during the heating process, obtain the partition wall surface temperature obtained after each group of temperature sensors monitors the temperature of different partitions in the wall surface; wherein different partitions in the wall surface correspond to different groups of the heaters and different groups of the temperature sensors; A temperature uniformity determination module, used to determine whether the temperatures of different partitions in the wall surface meet a preset temperature uniformity condition according to the partition wall surface temperature; The wall partition heating module is used to adjust each group of the heaters based on the preset target temperature and the partition wall temperature if the condition is not met, and control the adjusted heaters to continue heating the corresponding partitions in the wall, so as to end the heating process when the temperatures of different partitions in the wall meet the preset temperature uniformity condition and the temperature of any partition in the wall reaches the preset target temperature, so as to suppress the secondary instability of the Görtler vortex in the boundary layer generated by the fluid on the wall.

8. The device for suppressing Görtler vortex secondary instability based on wall heating according to claim 7, characterized in that: The wall temperature acquisition module comprises: The temperature determination unit is used to obtain the current monitoring temperature obtained by each temperature sensor in any group of the temperature sensors after monitoring the temperature of the same partition in the wall surface, and determine the partition wall temperature of any group of the temperature sensors based on the average value of each current monitoring temperature.

9. An electronic device, characterized in that: include: Memory, used to store computer programs; A processor, configured to execute the computer program to implement the method for suppressing Görtler vortex secondary instability based on wall heating as described in any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that: Used to store a computer program; wherein, when the computer program is executed by a processor, the method for suppressing Görtler vortex secondary instability based on wall heating as described in any one of claims 1 to 6 is implemented.

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