CN-121977979-A - Device and method for measuring sand dust concentration at inlet of helicopter engine

CN121977979ACN 121977979 ACN121977979 ACN 121977979ACN-121977979-A

Abstract

The invention discloses a device and a method for measuring the concentration of sand dust at an inlet of a helicopter engine, comprising the following steps: the annular electrostatic sensor is arranged on a transition section between an engine air inlet channel and the air compressor, the annular electrostatic sensor is attached to the inner wall surface of the transition section, an electrostatic sensor electromagnetic interference shield is additionally arranged around the annular electrostatic sensor, and the annular electrostatic sensor, the signal amplifier, the data acquisition unit and the data processor are sequentially connected through cables; in the running process, the measuring device adopts the annular electrostatic sensor to measure the induction charge generated by sand dust at the inlet of the engine, amplifies the induction charge through the signal amplifier, acquires the amplified induction charge through the data acquisition unit, and processes the induction charge by the data processor based on the calibration curve families of the sand dust concentration and the induction charge of the annular electrostatic sensor under different pre-obtained flight states, thereby obtaining the sand dust concentration at the inlet of the engine under different flight states.

Inventors

CHENG ZHAO
WANG JUNQI
LIU YU
GAO XIANG
WANG TAO

Assignees

中国飞行试验研究院

Dates

Publication Date: 20260505
Application Date: 20251227

Claims (8)

1. The device for measuring the sand dust concentration at the inlet of the helicopter engine is characterized by comprising an annular electrostatic sensor (1), a signal amplifier (2), a data acquisition unit (3), a data processor (4) and a cable (5), wherein the electrostatic sensor is an electromagnetic interference shielding device (6); the annular electrostatic sensor (1) is arranged on a transition section between an engine air inlet channel and a gas compressor, the annular electrostatic sensor (1) is attached to the inner wall surface of the transition section, an electrostatic sensor electromagnetic interference shield (6) is additionally arranged around the annular electrostatic sensor (1), and the annular electrostatic sensor (1), the signal amplifier (2), the data collector (3) and the data processor (4) are sequentially connected through a cable (5); The measuring device is used for measuring induction charges generated by sand dust at an inlet of an engine by adopting the annular electrostatic sensor (1) in flight, amplifying the induction charges through the signal amplifier (2), acquiring the amplified induction charges through the data acquisition device (3), and processing the induction charges by the data processor (4) based on calibration curve families of the sand dust concentration and the induction charges of the annular electrostatic sensor under different flight states obtained in advance to obtain the sand dust concentration at the inlet of the engine under different flight states.
2. The helicopter engine inlet dust concentration measurement apparatus of claim 1, comprising: The cable (5) between the annular electrostatic sensor (1) and the signal amplifier (2) is fixed on the outer wall surface of the air inlet passage transition section (7) so as to avoid interference of the cable (5) on the engine.
3. The helicopter engine inlet dust concentration measurement apparatus of claim 1, comprising: The signal amplifier (2), the data acquisition device (3) and the data processor (4) are all arranged in the helicopter cabin; the electromagnetic interference shielding device (6) of the electrostatic sensor is of an annular structure, and an annular groove is formed in the end face of the outer ring along the circumferential direction so as to install the annular electrostatic sensor (1) through the annular groove.
4. A method for measuring the sand and dust concentration at the inlet of a helicopter engine, which is characterized in that the method for measuring the sand and dust concentration at the inlet of the helicopter engine by adopting the device for measuring the sand and dust concentration at the inlet of the helicopter engine according to any one of claims 1-3 comprises the following steps: Step 1, determining parameters of an air inlet channel of a tested engine, and obtaining density distribution, particle size distribution and charge quantity distribution of local sand particles by measuring physical parameters of the local sand particles; Step 2, establishing a sand dust particle induction electric quantity calculation model of the annular electrostatic sensor (1), determining an effective measurement space of the annular electrostatic sensor (1) in a measurement device, and obtaining calibration curve families of sand dust concentration and induction electric quantity of the annular electrostatic sensor (1) under different flight states; And 3, carrying out sand and dust concentration characteristic measurement test on an inlet of the helicopter engine, adopting a measurement device of sand and dust concentration of the inlet of the helicopter engine according to test requirements, and measuring the sand and dust concentration of the inlet of the engine in different flight states based on calibration curve families of the sand and dust concentration and induced electricity of the annular electrostatic sensor (1) in different flight states.
5. The method for measuring the sand dust concentration at the inlet of a helicopter engine according to claim 4, wherein said step 1 comprises: Step 11, determining air inlet channel parameters of a tested engine of the helicopter, confirming the installation position and the sensor size of the annular electrostatic sensor (1) based on the air inlet channel parameters, and installing the annular electrostatic sensor; And 12, collecting sand and dust particles at an inlet of an engine through an annular electrostatic sensor (1) in the first test flight process of the helicopter, and obtaining physical parameters of the sand and dust particles sucked into the engine at different flight speeds when the helicopter flies in a local sand and dust environment, wherein the parameters comprise particle size composition, sand and dust composition and sand and dust charge composition of sucked sand and dust.
6. The method for measuring the sand dust concentration at the inlet of a helicopter engine according to claim 5, wherein said step 2 comprises: Step 21, establishing a calculation model of the induction electric quantity on the sand particles and the annular electrostatic sensor, namely a sand particle induction electric quantity calculation model according to the progressive sequence of the static single sand particles, the moving multiple sand particles and the moving sparse charged sand particle group; Step 22, according to the physical parameters of the sand dust particles sucked into the engine, which are obtained in the step 1, determining the effective measurement space of the annular electrostatic sensor by moving the relation between the magnitude of the induction electric quantity generated by the single sand dust particles to the annular electrostatic sensor and the measurement precision of the annular electrostatic sensor; Step 23, according to the physical parameters of the sand particles sucked into the engine obtained in the step 1, corresponding sand particle numbers of different sand particle concentrations in an effective measurement space are determined, geometric position information of the sand particles in the effective measurement space is generated, and the induction electric quantity of the different sand particle concentrations on the annular electrostatic sensor is calculated through a sand particle induction electric quantity calculation model so as to obtain induction electric quantity relations of the different sand particle concentrations and the annular electrostatic sensor; And 24, calibrating the relation between the sand and dust concentration and the induction electric quantity of the annular electrostatic sensor at different flying speeds, and establishing a calibration curve family of the sand and dust concentration and the induction electric quantity of the annular electrostatic sensor at different flying speeds.
7. The method for measuring the concentration of sand particles at the inlet of a helicopter engine according to claim 6, wherein the calculation model of the induction electric quantity of the sand particles in the step 21 is as follows: the magnitude of the induced electric field of sand particles in the space to a point on the sensor surface is as follows: ; wherein E is the electric field intensity, q is the charge quantity of the dust particles, The dielectric constant, r is the distance between sand and any position in space; The center of the annular electrostatic sensor is taken as the origin of coordinates to establish a coordinate system, and the induction charge quantity generated by any dust particles in the space on the annular electrostatic sensor can be calculated as follows: ; Wherein Q is the induction charge quantity generated on the annular electrostatic sensor, L is the diameter of the annular electrostatic sensor, y is the radial length of the sand and dust particles from the center of the annular electrostatic sensor, z is the axial length of the sand and dust particles from the center of the annular electrostatic sensor, w is the axial size of the annular electrostatic sensor, and θ is the [0,2 pi ] integration interval.
8. The method for measuring the sand dust concentration at the inlet of a helicopter engine according to claim 6, wherein said step 3 comprises: step 31, measuring the sand and dust concentration of an engine inlet under different hovering heights through a calibration curve family of the sand and dust concentration and the induction power of the annular electrostatic sensor (1) when the helicopter executes hovering action; And step 32, measuring the sand and dust concentration of an engine inlet in different flight states through a calibration curve family of the sand and dust concentration and the induction power of the annular electrostatic sensor (1) when the helicopter moves in a ground-near maneuver, wherein the different flight states comprise combination states of different flight speeds and different flight attitudes.

Description

Device and method for measuring sand dust concentration at inlet of helicopter engine Technical Field The invention relates to the technical field of aeroengine tests, in particular to a device and a method for measuring sand dust concentration at an inlet of a helicopter engine. Background When the prior aircraft tests and flies in the sand dust environment, the inlet of the engine can suck sand and dust which are rolled into the ground by the scroll. The sand particles have strong corrosiveness, and can lead to abrasion of the thin tail edges and tips of the working blades and the stator blades of the air compressor, reduce the working efficiency of the air compressor, and the small sand particles can also block cooling air holes of the turbine blades after entering the turbine, so that the turbine blades are over-heated and even ablated, thereby leading to the performance attenuation and service life reduction of the engine. Severely limiting the service life and range of use of the engine. The method for measuring the concentration of the sucked sand and dust at the inlet of the engine mainly adopts a weighing method, the collected sand and dust sucked by an air inlet channel in the flying process is collected through a collecting device arranged at an air inlet of the engine, and the average concentration of the sucked sand and dust at the inlet of the engine in the flying process is calculated based on the collected sand and dust after the flying is finished. Disclosure of Invention The invention aims to provide a device and a method for measuring the concentration of sand and dust at an inlet of a helicopter engine, which are used for solving the problem of the deficiency of the existing sand and dust concentration measuring technology. The technical scheme of the invention is that in the first aspect, the invention provides a device and a method for measuring the sand dust concentration at the inlet of a helicopter engine, wherein the device comprises an annular electrostatic sensor 1, a signal amplifier 2, a data collector 3, a data processor 4, a cable 5 and an electrostatic sensor electromagnetic interference shield 6; The annular electrostatic sensor 1 is arranged on a transition section between an engine air inlet channel and a gas compressor, the annular electrostatic sensor 1 is attached to the inner wall surface of the transition section, an electrostatic sensor electromagnetic interference shield 6 is additionally arranged around the annular electrostatic sensor 1, and the annular electrostatic sensor 1, the signal amplifier 2, the data collector 3 and the data processor 4 are sequentially connected through a cable 5; The measuring device is used for measuring induction charges generated by sand dust at an engine inlet by adopting the annular electrostatic sensor 1 in flight, amplifying the induction charges through the signal amplifier 2, acquiring the amplified induction charges through the data acquisition unit 3, and processing the induction charges by the data processor 4 based on calibration curve families of the sand dust concentration and the induction charges of the annular electrostatic sensor under different flight states obtained in advance to obtain the sand dust concentration at the engine inlet under different flight states. Optionally, in the device for measuring the sand dust concentration at the inlet of the helicopter engine, the device comprises: The cable 5 between the annular electrostatic sensor 1 and the signal amplifier 2 is fixed on the outer wall surface of the air inlet passage transition section 7, so that interference of the cable 5 to the engine operation is avoided. Optionally, in the device for measuring the sand dust concentration at the inlet of the helicopter engine, the device comprises: the signal amplifier 2, the data acquisition device 3 and the data processor 4 are all arranged in the helicopter cabin; The electromagnetic interference shielding device 6 of the electrostatic sensor is of an annular structure, and an annular groove is formed in the end face of the outer ring along the circumferential direction so as to mount the annular electrostatic sensor 1 through the annular groove. In a second aspect, the present invention also provides a method for measuring the sand and dust concentration at the inlet of a helicopter engine, which adopts the device for measuring the sand and dust concentration at the inlet of the helicopter engine according to any one of the above steps, and comprises: Step 1, determining parameters of an air inlet channel of a tested engine, and obtaining density distribution, particle size distribution and charge quantity distribution of local sand particles by measuring physical parameters of the local sand particles; Step 2, establishing a sand dust particle induction electric quantity calculation model of the annular electrostatic sensor 1, determining an effective measurement space of the annular electrostatic sensor 1 in