Sensing element

Abstract

A sensor element (1) for determining the lateral transition pressure of a shock wave (9), comprising a body (2) constructed along a longitudinal axis (X); the body (2) having a nose (3) and a measuring part (4); the nose being arranged adjacent to the measuring part (4); the nose tapering from the measuring part along the longitudinal axis to a nose tip (31); the measuring part having at least three pressure sensors; each of the at least three pressure sensors having a pressure-sensitive pressure acquisition surface (6); the pressure acquisition surface of each of the at least three pressure sensors being arranged parallel to the longitudinal axis; the at least three pressure sensors being arranged spaced apart (Dab, Dbc) from each other along the longitudinal axis. The sensor element is suitable for determining the velocity and acceleration of the shock wave. The present invention also provides the use of the sensor element for determining physical properties of the shock wave, a sensor device comprising the sensor element, and a method for determining physical properties of the shock wave using the sensor element.

Description

Technical Field

[0001] The invention relates to a sensor element for determining physical properties of a shock wave in a fluid and a method for determining physical properties of a shock wave in a fluid. Background Art

[0002] Shock waves or pressure waves can propagate in a medium (e.g., a fluid). The fluid is a gas or a liquid. In the following, the term "shock wave" is used to represent a pressure wave or shock wave.

[0003] Shock waves can occur in many situations. Sudden expansions in a fluid are associated with shock waves that propagate from the point of expansion. For example, expansions can occur through the rapid escape of fluid from an opening. For example, when a piston moves in a cylinder, shock waves can be triggered by the rapid movement of solids, such as by rapidly emptying a fluid-filled space or filling a previously largely empty space through an outlet. Expansions can also occur within a fluid. Similarly, implosions within a fluid are associated with shock wave propagation.

[0004] Shock waves can propagate unimpeded through space. They can also propagate in a directed manner, such as along the axis of a hollow cylinder.

[0005] A shock wave has a shock wave front that propagates through a fluid. Here, the shock wave front after expansion has a pressure increase relative to the unaffected fluid. The shock wave front after implosion has a pressure drop relative to the unaffected fluid. The following description only describes the case where the shock wave front is a shock wave with a pressure increase. However, those skilled in the art can adapt the following description of the present invention accordingly to a shock wave front with a pressure drop.

[0006] At a fixed location, a shock wave can be identified as an instantaneous pressure. Hereinafter, "instantaneous" always refers to an instant in time. Thus, instantaneous pressure is the pressure as a function of time. A shock wave propagating through that location can be identified as a pressure rise that reaches a maximum pressure, followed by a pressure drop.

[0007] Shock waves have a variety of physical properties. A shock wave has a maximum pressure. A shock wave has a time-varying pressure rise, manifested as a rise from the pressure of the unaffected fluid to the maximum pressure. A shock wave has a wavefront. The wavefront is defined at the location where the pressure rise has an inflection point. Alternatively, the wavefront can be defined at the location where the pressure reaches a height halfway between the pressure of the unaffected fluid and the maximum pressure. A shock wave has a decay time, defined at the location where the pressure drops from the maximum pressure to a certain proportion of the maximum pressure. A shock wave has a shockwave velocity, at which the shockwave front moves through the fluid. A shock wave has a shockwave acceleration. Typically, the velocity of the shockwave front decreases with increasing distance traveled. Therefore, in most cases, the shockwave acceleration is negative. However, it should be noted that positive shockwave acceleration is explicitly included below.

[0008] Patent document US2799788A discloses a sensing element for determining the instantaneous pressure of a shock wave. The sensing element has a main body arranged along a longitudinal axis, the main body having a nose and a measuring part. In order to measure the instantaneous pressure of the shock wave, the sensing element is oriented with the longitudinal axis perpendicular to the shock wave front. The nose is arranged adjacent to the measuring part and gradually tapers along the longitudinal axis to the nose tip. This avoids eddies and / or distortions of the shock wave front. Eddies or distortions can cause local pressure changes and cannot correctly determine the instantaneous pressure of the shock wave. A pressure sensor is arranged in the measuring part, which has a pressure-sensitive pressure acquisition surface transverse to the longitudinal axis. After excluding the proportional factor, the lateral pressure (also called lateral transition pressure) is equal to the instantaneous pressure of the shock wave. The disadvantage here is that neither the shock wave velocity nor the shock wave acceleration can be determined. Summary of the Invention

[0009] It is therefore an object of the present invention to provide a sensor with which the instantaneous pressure and the shock wave acceleration as well as the shock wave velocity of a shock wave can be determined simply and effectively.

[0010] This object is achieved through the technical solution of the present invention.

[0011] The present invention relates to a sensor element for determining the lateral transition pressure of a shock wave in a fluid, comprising a main body arranged along a longitudinal axis; the main body having a nose; the main body having a measuring part; wherein the nose is arranged adjacent to the measuring part; wherein the nose gradually tapers from the measuring part along the longitudinal axis to the nose tip; wherein the measuring part has at least three pressure sensors; wherein the pressure sensors have a pressure-sensitive pressure acquisition surface; wherein the pressure acquisition surface of each of the at least three pressure sensors is arranged parallel to the longitudinal axis; and wherein the at least three pressure sensors are arranged spaced apart from each other along the longitudinal axis.

[0012] The sensing element is arranged with its longitudinal axis parallel to the expected direction of propagation of the shock wave. The body has a nose portion, which is positioned to face the shock wave. The nose portion is designed to gradually compress the shock wave, thereby minimizing distortion of the shock wave and the accompanying localized perturbation of the shock wave pressure caused by this gradual compression as the shock wave's motive fluid flows through the sensing element. This makes the sensing element suitable for measuring the lateral transition pressure of the shock wave without excessive perturbation.

[0013] By adopting at least three pressure sensors arranged along the longitudinal axis, it is possible to easily determine multiple physical characteristics of the shock wave using only one sensing element, because at least three instantaneous pressures can be determined independently of each other as pressure signals. The spacing of the pressure sensors along the longitudinal axis is known. The at least three instantaneous pressure signals are determined at the positions of the pressure collection surfaces of the pressure sensors spaced apart from each other along the propagation direction of the shock wave. The temporal position (zeitliche Position) of the shock wave front is determined based on the rise of each pressure signal. The time difference between the at least three shock wave fronts is determined. Thus, the shock wave velocity can be determined based on the propagation time, that is, the time difference between the shock wave fronts determined by each of the three pressure sensors. Similarly, the shock wave acceleration can be determined based on the time difference between the at least three shock wave fronts and the known spacing of the pressure collection surfaces along the longitudinal axis. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0015] Figure 1 is a partial schematic diagram of an embodiment of a sensing element,

[0016] Figure 2 is a partial schematic diagram of another embodiment of the sensing element,

[0017] Figure 3 Based on Figure 1 Another partial schematic diagram of an embodiment of a sensing element,

[0018] Figure 4 Based on Figure 1 Another partial schematic diagram of an embodiment of the sensing element,

[0019] Figure 5 is a schematic diagram of the determined pressure signal,

[0020] Figure 6 is a partial schematic diagram of another embodiment of the sensing element,

[0021] Figure 7A schematic partial view of another embodiment of a sensor element with a detection unit is shown.

[0022] The reference numerals are as follows:

[0023] 1. Sensing element

[0024] 100 sensor devices

[0025] 11 Electronic unit

[0026] 12 flat part

[0027] 121 strings

[0028] 13 Cable

[0029] 14 Collection Unit

[0030] 15 Piezoelectric acceleration measuring element

[0031] 17 Piezoelectric pressure measuring element

[0032] 2 Main body

[0033] 3. Nose

[0034] 31 Tip of nose

[0035] 4. Measurement Department

[0036] 5. Pressure sensor

[0037] 6 Pressure collection surface

[0038] 70a, 70b, 70c pressure signal

[0039] 7a, 7b, 7c Pressure

[0040] 80a, 80b, 80c acceleration signals

[0041] 8a, 8b, 8c Acceleration

[0042] 9 Shockwave

[0043] a9 acceleration, shock wave acceleration

[0044] Dab, Dbc spacing

[0045] P pressure

[0046] T time

[0047] ta, tb, tc time

[0048] tab, tac, tbc time difference

[0049] v9 Speed

[0050] W propagation direction

[0051] X vertical axis

[0052] Xa, Xb, Xc positions DETAILED DESCRIPTION

[0053] Figure 1 An embodiment of a sensor element 1 for determining the lateral transition pressure of a shock wave 9 is shown. The sensor element comprises a body 2 arranged along a longitudinal axis X. The body 2 has a nose 3. The body 2 has a measuring portion 4. The nose 3 is arranged adjacent to the measuring portion 4. The nose 3 tapers from the measuring portion 4 along the longitudinal axis X to a nose tip 31. This configuration of the sensor element, particularly the nose 3, is advantageous because the impinging shock wave is gradually compressed as it flows through the sensor element. This prevents eddies and distortions in the shock wave.

[0054] According to the present invention, the measuring unit 4 includes at least three pressure sensors 5a, 5b, and 5c. Each of the at least three pressure sensors 5a, 5b, and 5c has a pressure-sensitive pressure collection surface 6. The pressure acting on the pressure collection surface is determined by the pressure sensor. The pressure collection surface 6 of each of the at least three pressure sensors 5a, 5b, and 5c is arranged parallel to the longitudinal axis X. Therefore, the pressure determined when the shock wave moves along the longitudinal axis of the sensor element is called the transverse pressure, also known as the transient transverse pressure or transverse transition pressure. The at least three pressure sensors 5a, 5b, and 5c are arranged spaced apart from each other along the longitudinal axis X. This has the advantage of allowing the propagation of the shock wave to be measured at three different and clearly defined locations along the propagation direction of the shock wave. Thus, for example, the decrease in the maximum pressure of the shock wave can be determined as the propagation time or distance of the shock wave increases.

[0055] Preferably, each of the at least three pressure sensors 5a, 5b, 5c is designed to determine an instantaneous pressure 7a, 7b, 7c acting on the corresponding pressure acquisition surface 6 and provide it as a pressure signal 70a, 70b, 70c. A schematic diagram of the determined pressure signals 70a, 70b, 70c is shown in FIG. Figure 5 At least three pressure signals are used to further analyze the physical characteristics of the shock wave.

[0056] Particularly preferably, each of the at least three pressure sensors 5a, 5b, 5c is designed to determine the instantaneous pressure 7a, 7b, 7c acting on the corresponding pressure acquisition surface 6, and additionally each of the at least three pressure sensors 5a, 5b, 5c is designed to determine the acceleration 8a, 8b, 8c of the corresponding pressure sensor 5a, 5b, 5c independently of the pressure 7a, 7b, 7c acting on the pressure acquisition surface 6. In this case, the sensor element 1 has an electronic unit 11, such as Figure 6 As shown. The electronics unit 11 is arranged in the measuring section. The electronics unit 11 generates the difference between the determined instantaneous pressure and the determined acceleration component (Anteil) as a pressure signal 70a, 70b, 70c and provides this pressure signal. This is advantageous because pressure sensors exposed to shock waves are generally also subject to acceleration. However, acceleration may also be at work in the pressure sensors 5a, 5b, 5c because the individual components of the pressure sensors or the measuring element themselves also act as vibrating masses and exert forces on the measuring element during acceleration. Therefore, the acceleration of the pressure sensors 5a, 5b, 5c can also generate a signal that could be misinterpreted as a pressure signal 70a, 70b, 70c. Therefore, the pressure sensors 5a, 5b, 5c are advantageously designed to detect the acceleration 8a, 8b, 8c and compensate for the resulting signal. This is performed in the electronics unit 11. In the simplest case, the electronics unit is an electrically conductive connection of two conductors. Acceleration compensation of a pressure sensor and its working principle are described in, for example, patent documents EP0902267A2 or WO06131015A2.

[0057] In one embodiment, the nose 3 is constructed to be substantially rotationally symmetrical with respect to the longitudinal axis X. The length of the nose along the longitudinal axis X is at least three times the maximum diameter of the nose in a cross section perpendicular to the longitudinal axis (e.g., the length of the nose along the longitudinal axis X is at least three times greater than the maximum diameter of the nose in a cross section perpendicular to the longitudinal axis). This has the advantage that the shock wave is only gradually compressed along the entire length of the nose when it impacts the nose tip 31 of the nose 3. This gradual change in the diameter of the nose avoids distortions and eddies.

[0058] In accordance with Figure 1 and Figure 3 In the embodiment of FIG. 5 , the nose 3 is configured to be conical.

[0059] In another embodiment, the nose 3 has an olive-shaped cross section in a section parallel to the longitudinal axis X, such as Figure 2 This configuration is known in the art of flying or floating bodies, which are supposed to have very little resistance when moving through a fluid. In this document, the term "olive" refers to a pointed, streamlined rotating body.

[0060] The measuring part 4 is designed to be substantially cylindrical along the longitudinal axis. The measuring part 4 is thus connected seamlessly and without protrusions to the nose part 3. This is advantageous because eddies or distortions of the shock wave 9 could occur in the region of the protrusions.

[0061] In one embodiment, the body 2 has a flat portion 12. The flat portion 12 has the shape of a chord 121 in a cross section perpendicular to the longitudinal axis X, such as Figure 4 The flat portion 12 is flat and extends at least partially along the longitudinal axis X and is spaced apart from the longitudinal axis X, as shown in FIG. Figure 2 As shown, the respective pressure-collecting surfaces 6 of the at least three pressure sensors 5a, 5b, and 5c are arranged parallel to the flat portion 12. This has the advantage that the body 2 has no protrusions in the area of ​​the measuring portion 3. This is advantageous because eddies or distortions of the shock wave 9 may occur in the area of ​​the protrusions. In one embodiment, the pressure-collecting surfaces 6 of the at least three pressure sensors 5a, 5b, and 5c are flush with the flat portion.

[0062] In another embodiment, the pressure collection surfaces 6 of at least three pressure sensors 5a, 5b, and 5c are arranged set back from the flattened portion 12 in the direction of the longitudinal axis X. In this embodiment, the main body 2 also lacks protrusions in the region of the measuring portion 3. This is advantageous because eddies or distortions of the shock wave 9 can occur in the region of the protrusions. However, since the pressure collection surfaces are subject to less shear forces in the direction of the longitudinal axis X, shifting the pressure collection surfaces rearward in the direction of the longitudinal axis X protects them.

[0063] In another embodiment not shown, the pressure collection surface is coated with a flexible protective layer. This flexible protective layer is, for example, a vinyl layer. The vinyl layer can be opaque. This is particularly advantageous when the pressure collection surface is constructed as a thin-walled membrane. "Thin-walled" is understood to mean a thickness of less than 0.2 mm. The flexible protective layer protects the pressure measuring element arranged behind the membrane from environmental influences, such as excessive thermal radiation. For example, if the shock wave is accompanied by electromagnetic waves, for example in the infrared region, the electromagnetic waves may generate a signal in the pressure measuring element, which may be misinterpreted as a pressure signal. The flexible protective layer can minimize this problem.

[0064] In a preferred embodiment, each of the at least three pressure sensors 5a, 5b, and 5c has at least one piezoelectric pressure measuring element 17; the pressure measuring element 17 is in effective connection with the pressure collection surface 6. When the pressure acting on the pressure collection surface is transmitted to the pressure measuring element 17, the pressure measuring element 17 is in effective connection with the pressure collection surface, and the pressure measuring element is thus designed to detect pressure as a physical variable. The piezoelectric pressure measuring element is made of a piezoelectric material. Piezoelectric materials include, for example, quartz, lanthanum gallium silicate (La3Ga5SiO 14 ), gallium orthophosphate (GaPO4), lithium niobate (LiNbO3), lithium tantalate (LiTaO3), aluminum phosphate (AlPO4), topaz, minerals from the tourmaline group, and lead titanate (PbTiO3). Quartz is particularly preferred in one embodiment of the pressure measuring element 17. Quartz is robust and relatively inexpensive. Piezoelectric materials generate piezoelectric charges when a force acts on a surface, which can be detected as a charge signal in a charge amplifier. Piezoelectric materials are popular in measurement technology because they have a high natural frequency and can therefore detect rapid changes in force, up to the natural frequency of the crystal. Therefore, they are well-suited for fast processes, such as determining the instantaneous pressure 7a, 7b, 7c of a shock wave in a fluid. Typical natural frequencies of pressure sensors 5a, 5b, 5c with piezoelectric pressure measuring elements 17 are up to 300 kHz.

[0065] Each of the at least three pressure sensors 5a, 5b, and 5c includes at least one piezoelectric accelerometer 15. This accelerometer 15 is designed to determine the acceleration 8a, 8b, and 8c of the pressure sensor 1 independently of the instantaneous pressure 7a, 7b, and 7c acting on the corresponding pressure sensing surface 6. As previously mentioned, this allows the pressure sensor's signal, which is caused by acceleration 8a, 8b, and 8c, to be compensated. In this application, the piezoelectric accelerometer also offers the aforementioned advantages.

[0066] The nose 3 is advantageously designed to be streamlined. The nose 3 is designed so that a shock wave 9 impinging on the nose 3 is gradually compressed as it moves along the longitudinal axis X. This advantageously avoids distortions or eddies of the shock wave.

[0067] The body 2 is made of metal or a metal alloy. Metals and metal alloys are highly resistant. The sensor element 1 is therefore resistant to damage caused by shock waves 9.

[0068] The sensor element 1 can also have the features of the various embodiments described. For example, the configuration of the nose can be easily combined with the choice of pressure measuring element.

[0069] Sensor element 1 is used to determine the physical properties of shock wave 9. The longitudinal axis X of sensor element 1 is oriented substantially parallel to the propagation direction W of shock wave 9. Nose tip 31 is oriented opposite to the propagation direction W of shock wave 9. Sensor element 1 determines at least three instantaneous pressures 7a, 7b, 7c and provides them as pressure signals 70a, 70b, 70c. "Providing a signal" should be understood as making the provided signal available for use in another application. "Providing" also includes storing the signal in an electronic memory and loading the signal from the memory. "Providing" also includes the option of displaying the signal on a display.

[0070] The acquisition unit 14 compares the three provided pressure signals 70a, 70b, 70c. The acquisition unit 14 determines at least one shock wave velocity v9 based on the time series (ta, tb, tc) of the at least three pressure signals 70a, 70b, 70c and provides the shock wave velocity. The shock wave velocity is determined by the quotient of the distance traveled and the time elapsed, where the distance traveled is the distance between the two pressure acquisition surfaces 6 of the two pressure sensors 5a, 5b, 5c, and the time elapsed is the time difference between the shock wave fronts 91 determined at the corresponding pressure sensors. Figure 7 The acquisition unit 14 is shown in FIG.

[0071] The acquisition unit 14 determines the shock wave acceleration a9 using the time series ta, tb, and tc of the shock wave front 91 impacting the at least three pressure sensors 5a, 5b, and 5c. The shock wave acceleration a9 is determined and provided based on the three pressure signals 70a, 70b, and 70c. To this end, the velocity v9 of the shock wave 9 between the first pressure sensor 5a and the second pressure sensor 5b is first determined as described above. Then, the velocity v9 of the shock wave between the second pressure sensor 5b and the third pressure sensor 5c is determined. Based on the changes in these two determined velocities v9, the acceleration a9 of the shock wave 9 can be determined. The acceleration a9 can be positive or negative. A negative acceleration a9 is referred to as a deceleration.

[0072] Sensing device 100 includes a sensing element 1, a cable 13, and a data acquisition unit 14. Cable 13 electrically connects sensing element 1 to data acquisition unit 14. Provided pressure signals 70a, 70b, and 70c are transmitted from sensing element 1 to data acquisition unit 14 via cable 13. Sensing element 1 is designed to detect at least three pressure signals 70a, 70b, and 70c. Furthermore, data acquisition unit 14 is designed to compare at least three pressure signals 70a, 70b, and 70c.

[0073] The following describes a method for determining the physical characteristics of shock wave 9. The method includes determining at least three instantaneous pressures 7a, 7b, 7c as pressure signals 70a, 70b, 70c. At least three instantaneous pressure signals 70a, 70b, 70c are determined at locations Xa, Xb, Xc spaced apart along the propagation direction W of shock wave 9. The temporal position ta, tb, tc of shock wave front 91 is determined based on the rise of each pressure signal 70a, 70b, 70c. Time differences tab, tac, tbc between the at least three shock wave fronts are determined. The time differences tab, tac, tbc are the time differences between the impact of shock wave front 91 at one of the three locations Xa, Xb, Xc and the impact of the shock wave front at another of the three locations Xa, Xb, Xc. The velocity v9 of shock wave 9, also referred to as shock wave velocity v9, is determined based on the at least three determined time differences tab, tac, tbc between shock wave front 91.

[0074] By determining the shock wave acceleration a9 and the shock wave velocity v9 together with the known instantaneous pressure, a comprehensive characterization of the shock wave can be achieved.

[0075] In the method for determining physical properties of shock wave 9, at least three pressure signals 70a, 70b, 70c are preferably determined and provided using sensor element 1. Here, the longitudinal axis of sensor element 1 is arranged parallel to the propagation direction W of shock wave 9 as described above.

[0076] Shock wave front 9 can be determined in various ways. In one embodiment of the method, shock wave front 91 is determined at the time point when the rising instantaneous pressure 7a, 7b, 7c of pressure signals 70a, 70b, 70c reaches half of the maximum pressure signal 70a, 70b, 70c. In another embodiment of the method, shock wave front 9 is determined at the time point when the rising instantaneous pressure 7a, 7b, 7c has an inflection point. Both embodiments allow the velocity v9 and acceleration a9 of shock wave 9 to be determined.

[0077] Furthermore, in one embodiment of the sensor element 1 with the piezoelectric pressure sensor element 17, the electronic unit 11 is designed as a charge amplifier, such as Figure 6 This has the advantage that the piezoelectric charge does not have to be transmitted via the cable 13 to the external acquisition unit 14. In the transmission of the charge, the cable 13 has at least 10 10 High ohmic insulation requirements. If the electronic unit 11 has a charge amplifier, long cables can be easily selected. This simplifies the sensor device 100 because the acquisition unit 14 can be placed at a safe distance from the shock wave.

[0078] The sensing element is designed to detect a pressure of a maximum of 1000 psi or approximately 69 bar. The sensing element is designed to withstand a pressure of a maximum of 5000 psi or approximately 350 bar without damage.

[0079] The embodiments of the method or sensor element 1 disclosed herein can of course be combined with one another. Embodiments having combinations of features of the embodiments described herein are also explicitly included herein.

Claims

1. A sensor device (100), comprising a sensor element (1) for determining the transverse transition pressure of a shock wave (9) acting along a longitudinal axis (X) in a fluid, a cable (13) and a collection unit (14); wherein the cable (13) electrically connects the sensor element (1) to the collection unit (14); wherein the sensor element (1) is designed to detect at least three pressure signals (70a, 70b, 70c); and wherein, The acquisition unit (14) is designed to compare the at least three pressure signals (70a, 70b, 70c) and to determine at least one shock wave velocity (v9) by means of a time series (ta, tb, tc) of the at least three pressure signals (70a, 70b, 70c) and to provide, The sensing element (1) comprises a body (2) arranged along a longitudinal axis (X); wherein the body (2) defines a nose (3); the body (2) defines a measuring portion (4); wherein the nose (3) is arranged adjacent to the measuring portion (4) and gradually tapers from the measuring portion (4) along the longitudinal axis (X) to a nose tip (31); wherein, in order to determine the lateral transition pressure of a shock wave (9) in a fluid, the body (2) is arranged with the longitudinal axis (X) parallel to the expected propagation direction of the shock wave (9); wherein, in order to determine the lateral transition pressure of the shock wave (9), the nose (3) is arranged to face the shock wave (9); wherein at least three pressure sensors (5a, 5b, 5c) are aligned along a longitudinal axis (X); wherein each of the at least three pressure sensors (5a, 5b, 5c) has a pressure-sensitive pressure collection surface (6); wherein the pressure collection surface (6) of each of the at least three pressure sensors (5a, 5b, 5c) is arranged parallel to the longitudinal axis (X); and wherein the at least three pressure sensors (5a, 5b, 5c) are arranged spaced apart (Dab, Dbc) from each other along the longitudinal axis (X).

2. The sensor device (100) according to claim 1, characterized in that Each of the at least three pressure sensors (5a, 5b, 5c) is designed to determine the instantaneous pressure acting on the corresponding pressure acquisition surface (6) and to provide the instantaneous pressure as a pressure signal (70a, 70b, 70c).

3. The sensor device (100) according to claim 1, characterized in that Each of the at least three pressure sensors (5a, 5b, 5c) is designed to determine the instantaneous pressure acting on the corresponding pressure collection surface (6); Each of the at least three pressure sensors (5a, 5b, 5c) is designed to determine the acceleration of the corresponding pressure sensor (5a, 5b, 5c) independently of the pressure acting on the pressure acquisition surface (6); the sensor element has an electronic unit (11); the electronic unit (11) is arranged in the measuring part (4); the electronic unit (11) generates and provides the difference between the determined instantaneous pressure and the component of the determined acceleration as a pressure signal (70a, 70b, 70c).

4. The sensor device (100) according to claim 2, characterized in that The nose (3) is essentially rotationally symmetrical with respect to the longitudinal axis (X), and the length of the nose along the longitudinal axis is at least three times the maximum diameter of the nose in a cross section perpendicular to the longitudinal axis; and the nose (3) is constructed to be conical, or the nose (3) has an olive-shaped cross section in a cross section parallel to the longitudinal axis (X).

5. The sensor device (100) according to claim 1, characterized in that The measuring portion (4) is configured to be substantially cylindrical along the longitudinal axis (X).

6. The sensor device (100) according to claim 5, characterized in that The main body (2) has a flat portion (12); the flat portion (12) has a chord (121) shape in a cross section perpendicular to the longitudinal axis (X); the flat portion (12) extends flatly at least partially along the longitudinal axis (X) and is spaced apart from the longitudinal axis (X); the respective pressure collection surfaces (6) of the at least three pressure sensors (5a, 5b, 5c) are arranged parallel to the flat portion (12); and the pressure collection surfaces (6) of the at least three pressure sensors (5a, 5b, 5c) are flush with the flat portion, or the pressure collection surfaces (6) of the at least three pressure sensors (5a, 5b, 5c) are arranged to be withdrawn from the flat portion (12) along the longitudinal axis (X).

7. The sensor device (100) according to any one of claims 2 to 6, characterized in that Each of the at least three pressure sensors (5a, 5b, 5c) has at least one piezoelectric pressure measuring element; the piezoelectric pressure measuring element is in operative connection with the pressure acquisition surface (6).

8. The sensor device (100) according to claim 7, characterized in that Each of the at least three pressure sensors (5a, 5b, 5c) has at least one piezoelectric acceleration measuring element; the piezoelectric acceleration measuring element is designed to determine the acceleration of the pressure sensor (1) independently of the instantaneous pressure acting on the corresponding pressure acquisition surface (6).

9. The sensor device (100) according to any one of claims 1 to 6, characterized in that The nose (3) is constructed to be streamlined; wherein the nose (3) is designed so that a shock wave (9) impinging on the nose (3) is gradually compressed while moving along the longitudinal axis (X).

10. The sensor device (100) according to any one of claims 1 to 6, characterized in that The main body (2) is made of a metal alloy.

11. A use of a sensor device (100) according to any one of claims 1 to 10 for determining physical properties of a shock wave (9); wherein the longitudinal axis (X) of the sensor element (1) is substantially parallel to the propagation direction (W) of the shock wave (9); wherein the sensor element (1) determines at least three instantaneous pressures and provides the instantaneous pressures as pressure signals (70a, 70b, 70c); wherein a detection unit (14) compares the three provided pressure signals (70a, 70b, 70c); wherein the detection unit (14) determines at least one shock wave velocity (v9) by means of a time series (ta, tb, tc) of the at least three pressure signals (70a, 70b, 70c) and provides it; wherein the detection unit (14) determines at least one shock wave acceleration (a9) by means of a time series (ta, tb, tc) of the at least three pressure signals (70a, 70b, 70c) and provides it.

12. A method for determining physical properties of a shock wave (9) using a sensor device (100) according to any one of claims 1 to 10, characterized in that At least three instantaneous pressures are determined as pressure signals (70a, 70b, 70c); at least three instantaneous pressure signals (70a, 70b, 70c) are determined at positions (Xa, Xb, Xc) spaced apart from each other along the propagation direction (W) of the shock wave (9); the time position (ta, tb, tc) of the shock wave front is determined based on the rise of each pressure signal (70a, 70b, 70c); the time difference (tab, tac, tbc) between at least three shock wave fronts is determined; the shock wave velocity (v9) is determined based on the time difference (tab, tac, tbc) between the at least three determined shock wave fronts; and the shock wave acceleration (a9) is determined based on the time difference (tab, tac, tbc) between the at least three determined shock wave fronts.

13. Method for determining physical properties of a shock wave (9) according to claim 12, characterized in that The at least three pressure signals (70a, 70b, 70c) are determined and provided using a sensor device (100) according to any one of claims 1 to 10; wherein the longitudinal axis of the sensor element (1) is parallel to the propagation direction (W) of the shock wave (9).

14. Method for determining physical properties of a shock wave (9) according to claim 12 or 13, characterized in that The shock wave front is determined at a time point when the rising instantaneous pressure of the pressure signal (70a, 70b, 70c) reaches half of the maximum pressure signal (70a, 70b, 70c); or it is characterized in that the shock wave front is determined at a time point when the rising instantaneous pressure has an inflection point.

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