A device and method for measuring airspeed based on heat loss

Abstract

The application relates to a heat-loss-based airspeed measuring device and measuring method, and belongs to the technical field of airspeed measurement. The device solves the problems that the airspeed measured by the airspeed tube cannot reflect the influence of the lateral airflow on the aircraft and measurement errors are prone to occur in the prior art. The device comprises a measuring object with a windward side and a leeward side, a reference object which is completely identical to the measuring object, a wind shield arranged on the outer periphery of the reference object, a first temperature measuring element for measuring the temperature of the measuring object, a second temperature measuring element for measuring the temperature of the reference object, a third temperature measuring element for measuring the air temperature at a position with a preset distance between the leeward side of the measuring object and the measuring object, and a fourth temperature measuring element for measuring the ambient temperature. In the application, the airspeed obtained based on the temperature data can reflect the influence of the airflow on the aircraft in each direction, and the measurement errors prone to occur when the airspeed is measured by the airspeed tube can be avoided.

Description

Technical Field

[0001] This invention relates to the field of airspeed measurement technology, and in particular to an airspeed measurement device and method based on heat loss. Background Technology

[0002] Airspeed is the speed of the airflow around an aircraft, and also the speed of the aircraft relative to the airflow. Airspeed is a necessary parameter for calculating the aerodynamics of an aircraft; the higher the airspeed, the greater the lift the aircraft generates.

[0003] In existing technologies, pitot tubes are commonly used to measure the airspeed of aircraft. A pitot tube, also known as a pitot line or total-static tube, is a hollow tube with dynamic and static pressure ports. It measures airspeed using air pressure, and some pitot tubes also include sensors to measure wind direction. However, using pitot tubes to measure airspeed has the following main problems: 1. Pitot tubes can only measure airspeed in the forward direction (flight direction) and cannot reflect the influence of crosswinds. For low-speed aircraft, crosswinds have a significant impact on their flight attitude. 2. Because pitot tubes measure airspeed using air pressure, their angle requirements are very high. When the aircraft's attitude changes, the air pressure data measured by the pitot tube will change abruptly, causing measurement errors. 3. Impurities can easily enter the vent holes on the pitot tube, causing blockages, especially in dusty weather. When the aircraft takes off or lands, impurities in the air will be adsorbed inside the pitot tube, resulting in measurement errors. Furthermore, since the pitot tube is a hollow long tube, it is difficult to clean the impurities inside. Summary of the Invention

[0004] In view of the above analysis, the present invention aims to provide an airspeed measurement device and method based on heat loss, so as to solve the problems in the prior art where the airspeed measured by the airspeed tube cannot reflect the influence of the lateral airflow on the aircraft and the measurement error is prone to occur due to measurement angle deviation, impurity blockage, etc.

[0005] On one hand, embodiments of the present invention provide an airspeed measurement device based on heat loss, the device comprising:

[0006] The object being measured has a windward side and a leeward side;

[0007] A reference object that is identical to the object being measured;

[0008] A wind shield, which is disposed on the outer periphery of the reference object;

[0009] A first temperature measuring element is used to measure the temperature of the object being measured;

[0010] A second temperature measuring element is used to measure the temperature of the reference object;

[0011] The third temperature measuring element is used to measure the air temperature on the leeward side of the object being measured and at a preset position, wherein the preset position is spaced a preset distance from the object being measured; and

[0012] The fourth temperature measuring element is used to measure ambient temperature.

[0013] Based on further improvements to the above-described device, both the measuring object and the reference object include a housing and a liquid filled in the housing to slow down cooling.

[0014] Based on further improvements to the above-mentioned device, the airspeed measuring device also includes:

[0015] A first heater is used to heat the measured object; and

[0016] A second heater is used to heat the reference object.

[0017] Based on further improvements to the above-mentioned device, both the measuring object and the reference object are spheres.

[0018] Based on a further improvement of the above device, a wind-gathering plate is provided at a position 1cm to 2cm away from the object being measured on the leeward side of the object being measured.

[0019] The air-gathering plate is an arc-shaped plate, and the concave surface of the air-gathering plate faces the measuring object. The third temperature measuring element is disposed on the concave surface of the air-gathering plate.

[0020] Based on further improvements to the above-mentioned device, the windproof cover has a windward side and a leeward side, and the leeward side of the windproof cover has an opening.

[0021] On the other hand, the present invention provides a method for measuring heat loss airspeed, the method comprising:

[0022] Identical measuring objects and reference objects are set at preset positions on the aircraft, wherein the measuring objects are exposed to the air and the reference objects are set inside the windshield.

[0023] The temperature of the measured object and the reference object is measured, and the air heat dissipation power is obtained based on the temperature of the measured object and the reference object;

[0024] The ambient temperature of the aircraft and the air temperature at a predetermined distance from the object being measured on the leeward side are measured, and the temperature difference between the two is calculated to obtain the air temperature difference.

[0025] The airspeed of the aircraft is calculated based on the air heat dissipation power and the air temperature difference.

[0026] A further improvement to the above method involves determining the temperatures of the measured object and the reference object, and obtaining the air heat dissipation power based on the temperatures of the measured object and the reference object, including:

[0027] The temperature of the measured object and the reference object is the same at the initial moment;

[0028] After a preset time, the temperatures of the measuring object and the reference object are measured respectively;

[0029] The air heat dissipation power is calculated based on the temperatures of the measured object and the reference object measured after a preset time.

[0030] Based on a further improvement to the above method, the air heat dissipation power is calculated according to the following formula:

[0031] W = cm(T1-T0) / t;

[0032] In the formula, W is the air heat dissipation power, c is the specific heat capacity of air; m is the mass of the measured object and the reference object; T1 and T0 are the temperatures of the reference object and the measured object after a preset time t from the initial time, respectively.

[0033] Based on a further improvement of the above method, the airspeed of the aircraft is calculated according to the following formula:

[0034]

[0035] In the formula, V T Let W be the airspeed of the aircraft, W be the air heat dissipation power, ρ be the air density, c be the specific heat capacity of air, and ΔT be the air velocity. air This refers to the air temperature difference.

[0036] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0037] 1. This invention provides an airspeed measurement device and method based on heat loss. Airspeed can be calculated based on temperature data such as the temperature of the object being measured, the temperature of a reference object, the air temperature at a predetermined distance between the leeward side of the object and the object being measured, and the ambient temperature. Unlike pressure data, temperature data is non-directional. Therefore, the airspeed calculated based on temperature data in this invention can reflect the airflow influence on the aircraft in all directions (including forward and lateral), thus solving the problem that airspeed measured by a pitot tube cannot reflect the influence of lateral airflow on the aircraft. Simultaneously, the temperature data is not affected by the aircraft's attitude, thereby avoiding measurement errors caused by pitot tube deviations in measurement angle.

[0038] In addition, the airspeed measuring device of the present invention has a simple structure, with the measuring object exposed to the air and the reference object set in the windproof cover. Unlike the hollow long tube structure of the airspeed tube, it is less prone to measurement error problems caused by impurities clogging the tube.

[0039] 2. In this invention, airspeed is calculated based on the principle of airflow heat dissipation, specifically, based on air heat dissipation power and air temperature difference. Specifically, the air temperature difference is the temperature difference of the air flowing over the object being measured. This air temperature difference can be obtained from the ambient temperature difference and the air temperature at a predetermined distance from the object on its leeward side. When obtaining the air heat dissipation power, considering the heat transfer between the heat source and the air, a reference object identical to the object being measured is set up and placed inside a windproof cover. By comparing the temperature difference between the object being measured and the reference object, the heat dissipation generated by the airflow can be obtained, thus acquiring accurate air heat dissipation efficiency and ensuring accurate airspeed calculation results.

[0040] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0041] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0042] Figure 1 This is a schematic diagram of the airspeed measuring device according to an embodiment of the present invention;

[0043] Figure 2 This is a schematic diagram of the airspeed measurement method based on heat loss according to an embodiment of the present invention.

[0044] Figure label:

[0045] 1. Measured object; 2. Reference object; 3. Windproof cover; 4. First temperature measuring element;

[0046] 5. Second temperature measuring element; 6. Third temperature measuring element;

[0047] 7. Fourth temperature measuring element; 8. Air concentrator; 9. First heater;

[0048] 10. Second heater. Detailed Implementation

[0049] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0050] On one hand, embodiments of the present invention provide an airspeed measurement device based on heat loss, as shown in the figure. Figure 1 As shown, the device includes: a measuring object 1, a reference object 2, a windproof cover 3, a first temperature measuring element 4, a second temperature measuring element 5, a third temperature measuring element 6, and a fourth temperature measuring element 7. The measuring object 1 has a windward side and a leeward side. The reference object 2 is identical to the measuring object 1. The windproof cover 3 is disposed on the outer periphery of the reference object 2. The first temperature measuring element 4 measures the temperature of the measuring object 1, the second temperature measuring element 5 measures the temperature of the reference object 2, the third temperature measuring element 6 measures the air temperature at a predetermined distance from the leeward side of the measuring object 1, and the fourth temperature measuring element 7 measures the ambient temperature.

[0051] It should be noted that the ambient temperature mentioned above refers to the ambient temperature of the measuring object 1 and the reference object 2, which reflects the temperature of the air before it flows past the measuring object 1. The air temperature at a predetermined distance from the measuring object 1 on its leeward side reflects the temperature of the air after it flows past the measuring object 1. Preferably, the predetermined distance is 1 cm to 2 cm.

[0052] The fact that reference object 2 is completely identical to measuring object 1 means that reference object 2 and measuring object 1 are identical in terms of material, shape, volume, mass, and structure.

[0053] Specifically, both the measuring object 1 and the reference object 2 are spheres. Using spheres to contact the airflow helps reduce wind resistance.

[0054] In practice, the measuring object 1 and the reference object 2 are respectively set at a preset position on the aircraft, such as the nose of the aircraft, through corresponding mounting components or brackets.

[0055] Compared with existing technologies, in this embodiment of the invention, airspeed can be calculated based on temperature data such as the temperature of the measuring object 1, the temperature of the reference object 2, the air temperature at a predetermined distance between the leeward side of the measuring object 1 and the measuring object 1, and the ambient temperature. Unlike pressure data, temperature data is non-directional. Therefore, the airspeed calculated based on temperature data in this invention can reflect the airflow influence on the aircraft in all directions (including forward and lateral), thus solving the problem that airspeed measured by a pitot tube cannot reflect the influence of lateral airflow on the aircraft. Simultaneously, the temperature data is not affected by the aircraft's attitude, thereby avoiding measurement errors caused by pitot tube deviations.

[0056] In addition, the airspeed measuring device of the present invention has a simple structure. The measuring object 1 is exposed to the air, and the reference object 2 is set in the windproof cover 3. Unlike the hollow long tube structure of the airspeed tube, it is less prone to measurement error problems caused by impurities clogging the tube.

[0057] In this embodiment of the invention, airspeed is calculated based on the principle of heat dissipation through airflow. Air dissipation refers to the process by which heat is exchanged between the air and an object, causing the object's temperature to decrease. The faster the airflow, the greater the heat loss from the object's surface. Therefore, the current airflow speed can be calculated based on the heat lost by the object.

[0058] Specifically, when calculating airspeed based on the principle of airflow heat dissipation, two parameters are needed: air heat dissipation power and air temperature difference. The air temperature difference is the temperature difference of the air flowing through the measuring object 1, which can be obtained from the ambient temperature difference and the air temperature on the leeward side of the measuring object 1.

[0059] When obtaining the heat dissipation power of air, the heat transfer between the heat source object and the air must be considered. Because the heat source object in air at different temperatures undergoes heat transfer not only due to airflow but also due to temperature differences, the heat carried away by airflow cannot be directly obtained by measuring the temperature change of object 1; that is, the heat dissipation power of air cannot be directly obtained.

[0060] To address the heat transfer issue between the heat source and the air, this invention includes a reference object 2 identical to the object being measured (1), housed within a windproof shield (3). The object being measured (1) is exposed to the air, directly contacting the airflow, and dissipates heat through both heat transfer and airflow. The reference object 2, however, is housed within the shield and dissipates heat solely through heat transfer. By comparing the temperature difference between the object being measured (1) and the reference object 2, the heat dissipation of the object being measured due to airflow can be determined, thus obtaining a precise air cooling efficiency and ensuring accurate airspeed calculations.

[0061] In one embodiment, both the measuring object 1 and the reference object 2 include a housing and a liquid filled in the housing to slow down cooling.

[0062] Air at high altitudes flows at high speeds, resulting in extremely rapid heat dissipation. Ordinary heat sources quickly cool to ambient temperature, making measurement impossible. Therefore, in this embodiment of the invention, to address the problem of excessively rapid heat dissipation, a liquid with a high specific heat capacity is used as the primary carrier for temperature measurement. This allows the measured object 1 and the reference object 2 to cool down slowly during the heat dissipation process, facilitating measurement.

[0063] Preferably, the liquid is water. The specific heat capacity of water is 4.2 kJ / kg·℃, that is, for every 4.2 kJ of heat absorbed by 1 kg of water, the temperature rises by 1℃.

[0064] Specifically, the shell is made of a metallic material. Metallic materials have high thermal conductivity, and the metallic shell will not affect the heat dissipation of the liquid inside.

[0065] Specifically, the outer surfaces of both the measuring object 1 and the reference object 2 are designed as spherical, ellipsoidal, or streamlined surfaces to enable uniform heat dissipation and reduce wind resistance.

[0066] Specifically, the first temperature measuring element 4 and the second temperature measuring element 5 are respectively disposed in the receiving cavities inside the housings of the measuring object 1 and the reference object 2, so as to measure the temperature of the liquid in the receiving cavity.

[0067] In one embodiment, the apparatus further includes a first heater 9 and a second heater 10, wherein the first heater 9 is used to heat the measuring object 1 and the second heater 10 is used to heat the reference object 2.

[0068] In this embodiment of the invention, the heat supply for the measuring object 1 and the reference object 2 is also considered. During the heat dissipation process, the temperature of the measuring object 1 and the reference object 2 will gradually decrease to the ambient temperature, so heat supply is required to meet the measurement requirements.

[0069] In practice, the first heater 9 and the second heater 10 simultaneously heat the measuring object 1 and the reference object 2 with equal power consumption to compensate for heat loss and restore the temperature of the measuring object 1 and the reference object 2 to a temperature that meets the requirements for airspeed measurement. When the temperature reaches the predetermined value, heating of the ball is stopped, and heating is resumed when the temperature drops to a certain value.

[0070] Specifically, the first heater 9 and the second heater 10 can be heating rods. More specifically, the first heater 9 and the second heater 10 are respectively disposed in the receiving cavities inside the housings of the measuring object 1 and the reference object 2 to heat the liquid in the receiving cavities.

[0071] In a preferred embodiment, a wind-gathering plate 8 is provided at a predetermined distance from the leeward side of the measuring object 1. The wind-gathering plate 8 is an arc-shaped plate, and the concave surface of the wind-gathering plate 8 faces the measuring object 1. The third temperature measuring element 6 is disposed on the concave surface of the wind-gathering plate 8.

[0072] Among them, the air-gathering plate 8 with its arc-shaped structure can gather air from the sides to the center, so as to facilitate the measurement of air temperature.

[0073] In a preferred embodiment, the windproof cover 3 has a windward side and a leeward side, and the leeward side of the windproof cover 3 has an opening.

[0074] The windproof cover 3 has an opening on its leeward side, which allows the interior of the windproof cover 3 to communicate with the outside, thereby ensuring that the reference object 2 and the air can fully conduct heat exchange, while preventing airflow from passing over the reference object 2.

[0075] Furthermore, the windproof cover 3 is made of a metal material with high thermal conductivity to ensure that the reference object 2 can fully conduct heat transfer with the air.

[0076] In addition, the first temperature measuring element 4, the second temperature measuring element 5, the third temperature measuring element 6, and the fourth temperature measuring element 7 can all be temperature sensors.

[0077] On the other hand, embodiments of the present invention also provide a method for measuring airspeed based on heat loss, such as... Figure 2 As shown. The method includes:

[0078] Step 1: Set up identical measuring object 1 and reference object 2 at a preset position on the aircraft, wherein the measuring object 1 is exposed to the air and the reference object 2 is placed inside the wind shield 3;

[0079] Step 2: Measure the temperature of the measuring object 1 and the reference object 2, and obtain the air heat dissipation power based on the temperatures of the measuring object 1 and the reference object 2;

[0080] Step 3: Measure the ambient temperature of the aircraft and the air temperature at a predetermined distance from the leeward side of the measuring object 1, and calculate the temperature difference between the two to obtain the air temperature difference.

[0081] Step 4: Calculate the airspeed of the aircraft based on the air heat dissipation power and the air temperature difference.

[0082] Compared with existing technologies, the airspeed measurement method of the present invention can calculate airspeed based on temperature data such as the temperature of the measuring object 1, the temperature of the reference object 2, the temperature on the leeward side of the measuring object 1, and the ambient temperature. Unlike pressure data, temperature data is non-directional. Therefore, the airspeed calculated based on temperature data in this invention can reflect the airflow influence on the aircraft in all directions (including forward and lateral), thus solving the problem that airspeed measured by a pitot tube cannot reflect the influence of lateral airflow on the aircraft. Simultaneously, the temperature data is not affected by the aircraft's attitude, thereby avoiding measurement errors caused by pitot tube deviations in measurement angle.

[0083] In this embodiment of the invention, airspeed is calculated based on the principle of airflow heat dissipation, specifically, based on air heat dissipation power and air temperature difference. Specifically, the air temperature difference is the temperature difference of the air flowing through the measuring object 1, which can be obtained from the ambient temperature difference and the air temperature on the leeward side of the measuring object 1. When obtaining the air heat dissipation power, considering the heat transfer problem between the heat source object and the air, a reference object 2 identical to the measuring object 1 is set up and placed inside the windproof cover 3. By comparing the temperature difference between the measuring object 1 and the reference object 2, the heat dissipation generated by the airflow of the measuring object 1 can be obtained, thus obtaining accurate air heat dissipation efficiency and ensuring accurate airspeed calculation results.

[0084] Specifically, step 2 involves measuring the temperatures of the measuring object 1 and the reference object 2, and obtaining the air heat dissipation power based on the temperatures of the measuring object 1 and the reference object 2, including:

[0085] Step 21: Make the temperature of the measuring object 1 and the reference object 2 the same at the initial moment;

[0086] Step 22: After a preset time, measure the temperature of the measuring object 1 and the reference object 2 respectively;

[0087] Step 23: Calculate the air heat dissipation power based on the temperatures of the measuring object 1 and the reference object 2 measured after a preset time.

[0088] The air heat dissipation power is calculated according to the following formula:

[0089] W = cm(T1-T0) / t;

[0090] In the formula, W is the air heat dissipation power, c is the specific heat capacity of air; m is the mass of measuring object 1 and reference object 2; T1 and T0 are the temperatures of reference object 2 and measuring object 1 after a preset time t from the initial time, respectively.

[0091] In step 4, the airspeed of the aircraft is calculated according to the following formula:

[0092]

[0093] In the formula, V T Let W be the airspeed of the aircraft, W be the air heat dissipation power, ρ be the air density, c be the specific heat capacity of air, and ΔT be the air velocity. air This refers to the air temperature difference.

[0094] In practice, the specific heat capacity of air is 1.013 kJ / kg·℃ at -50℃, 1.009 kJ / kg·℃ at -20 to 10℃, and 1.017 kJ / kg·℃ at 50℃. Considering the small change in air specific heat capacity at these temperatures and the low air temperature at higher altitudes, the actual calculation uses the air specific heat capacity value of 1.009 kJ / kg·℃ at 0℃.

[0095] Meanwhile, the air density ρ is calculated according to the following formula:

[0096] ρ=1.293×(P r -P s )×(273 / (273+T0));

[0097] In the formula, p r p is the actual atmospheric pressure. s T0 is the standard atmospheric pressure and T0 is the ambient temperature.

[0098] The actual atmospheric pressure can be obtained through an onboard barometric pressure sensor or calculated using a formula based on the current flight altitude. Standard atmospheric pressure is 101325 Pa.

[0099] Furthermore, considering the potential dissipation error between the calculated airspeed and the actual airspeed, an error compensation value needs to be added to the calculated result. This error compensation value can be calculated using a standard calibration environment that simulates airspeed.

[0100] It should be noted that the airspeed measurement method of the present invention can be implemented by the airspeed measurement device of the present invention, so the airspeed measurement method and airspeed measurement device of the present invention can achieve the same effect.

[0101] Example

[0102] In this embodiment, both the measuring object 1 and the reference object 2 include: a shell and water filled in the shell, wherein the shell is filled with 0.1 kg of water.

[0103] Reference object 2 and measuring object 1 have the same initial temperature, and the temperature difference between them over a unit of time is 1.6℃. Using the formula W = cm(T1 - T0) / t, the air heat dissipation power W = 0.672 × 10⁻⁶. 3 W.

[0104] The actual atmospheric pressure is 70.11 hPa, the standard atmospheric pressure is 101.325 hPa, the ambient temperature is 10℃, and the air temperature at a position 2 cm away from the leeward side of the measuring object 1 is 22℃.

[0105] According to the formula ρ=1.293×(P) r-P s The air density ρ is calculated to be 0.86302 g / cm³. 3 .

[0106] According to the formula Calculate V T = 64.31 m / s.

[0107] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware, and the program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.

[0108] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An airspeed measuring device based on heat loss, characterized in that, The device includes: The object being measured has a windward side and a leeward side; A reference object that is identical to the object being measured; A wind shield, which is disposed on the outer periphery of the reference object; A first temperature measuring element is used to measure the temperature of the object being measured; A second temperature measuring element is used to measure the temperature of the reference object; A third temperature measuring element is used to measure the air temperature at a location on the leeward side of the object being measured, at a predetermined distance from the object; and The fourth temperature measuring element is used to measure ambient temperature; Both the measuring object and the reference object include a housing and a liquid filled in the housing to slow down cooling; The shell is made of metal. A wind-gathering plate is provided at a predetermined distance from the leeward side of the object being measured. The wind-gathering plate is an arc-shaped plate, and the concave surface of the wind-gathering plate faces the object being measured. The third temperature measuring element is disposed on the concave surface of the wind-gathering plate. The preset distance is 1cm to 2cm; The windproof cover has a windward side and a leeward side, and the leeward side of the windproof cover has an opening.

2. The airspeed measuring device according to claim 1, characterized in that, The outer surfaces of both the measuring object and the reference object are configured as spherical, ellipsoidal, or streamlined surfaces.

3. The airspeed measuring device according to claim 1 or 2, characterized in that, The device further includes: A first heater is used to heat the measured object; and A second heater is used to heat the reference object.

4. A method for measuring heat loss space velocity, characterized in that, The method includes: Identical measuring objects and reference objects are set at preset positions on the aircraft, wherein the measuring objects are exposed to the air and the reference objects are set inside the windshield. The temperature of the measured object and the reference object is measured, and the air heat dissipation power is obtained based on the temperature of the measured object and the reference object; The ambient temperature of the aircraft and the air temperature at a predetermined distance from the object being measured on the leeward side are measured, and the temperature difference between the two is calculated to obtain the air temperature difference. The airspeed of the aircraft is calculated based on the air heat dissipation power and the air temperature difference. The step of measuring the temperature of the measured object and the reference object, and obtaining the air heat dissipation power based on the temperatures of the measured object and the reference object, includes: The temperature of the measured object and the reference object is the same at the initial moment; After a preset time, the temperatures of the measuring object and the reference object are measured respectively; The air heat dissipation power is calculated based on the temperatures of the measured object and the reference object measured after a preset time.

5. The method according to claim 4, characterized in that, The air cooling power is calculated according to the following formula: ； In the formula, For air heat dissipation power, The specific heat capacity of air; For the mass of the object being measured and the reference object; and These are the temperatures of the reference object and the measured object after a preset time t, respectively, from the initial moment.

6. The method according to claim 4 or 5, characterized in that, Calculate the airspeed of the aircraft using the following formula: ； In the formula, The airspeed of the aircraft. For air heat dissipation power, air density, The specific heat capacity of air, This refers to the air temperature difference.

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