CN115452311A - Icing cloud measuring equipment and icing cloud measuring method - Google Patents

Abstract

The invention provides a freezing cloud and mist measuring device, which comprises: a grille arrangement comprising: a grid frame; the transverse grid bars and the longitudinal grid bars are arranged in the grid frame in a criss-cross manner; ice sheet thickness measuring device, ice sheet thickness measuring device includes: an imaging device arranged to image the ice layer at designated measuring points on the transverse and longitudinal grid bars from the front of the grid device to obtain an image of the ice layer and thereby measure the thickness of the ice layer in a non-contact manner. Hereby it is achieved that the thickness of the ice layer on the grid arrangement can be measured in a non-contact manner. In addition, the invention also provides a method for measuring the icing cloud fog.

Description

Icing cloud measuring equipment and icing cloud measuring method

Technical Field

The invention belongs to the technical field of icing wind tunnel measurement, and particularly relates to icing cloud and mist measuring equipment and an icing cloud and mist measuring method, which can be used for efficiently and accurately measuring the cloud and mist field uniformity of a target position of an airplane ground icing test.

Background

In the airworthiness evidence-obtaining test, an icing test under the ground frozen fog condition is required to be carried out on the airplane, particularly the civil airplane, so as to show the conformance to relevant sections in CCAR 25 transport airplane airworthiness standard. The standard explicitly specifies that the frozen fog environment is: at the temperature of minus 9 ℃ to minus 1 ℃ (15 ℃ F. To 30 ℃ F.), the liquid water content is not less than 0.3g/m < 3 >, the water is in a water drop state (the average effective diameter is not less than 20 mm), and the like. Liquid water content refers to the total mass of liquid droplets contained in a unit volume of gas flow.

The method is characterized in that a large amount of time is usually spent on searching for the frozen fog environment meeting the requirements of the terms of the airworthiness standard of transport airplanes in the natural environment, and the duration time of the natural frozen fog environment is indefinite. Therefore, the ground icing test of the civil aircraft mostly adopts artificial frozen fog environment at present. The test objects related to the clause in the transport-class airplane airworthiness standard are systems such as an APU (auxiliary power unit) air inlet system and a turbine engine of a civil airplane generally. In order to ensure that the freezing fog conditions borne by different parts of a test object are basically consistent and that the test result at the freezing fog parameter test position can represent the real freezing condition near the test object, the uniformity of the artificial freezing fog environment must meet the test requirement, and the uniformity of the Liquid Water Content (LWC) of the general artificial freezing fog environment is better than 20%.

The method for measuring the uniformity of the conventional artificial frozen fog environment (LWC) is carried out by an icing grid under the condition that the ambient static temperature is lower than-18 ℃. The icing grid is formed by a plurality of flat grid strips which are staggered horizontally and vertically, the horizontal grid strips are vertical to the vertical grid strips, and the horizontal grid strips and the vertical grid strips are uniformly distributed. After the icing grid is placed in a freezing fog environment for a period of time for icing, the uniformity of the thickness of the ice frozen on the measuring point can reflect the spatial uniformity of the LWC. Therefore, the grid icing thickness measurement method directly affects the precision and test efficiency of the artificial frost fog environment (LWC) uniformity.

In the conventional method for measuring the uniformity of the artificial freezing fog environment (LWC), a vernier caliper is usually adopted to measure the thickness of a grid and the thickness of the grid plus accumulated ice, and the accumulated ice thickness of a measuring point is indirectly obtained through calculation. However, these prior arts have the following problems:

firstly, because the thickness of the clean grating and the thickness of the frozen grating are measured manually, error accumulation and artificial errors are inevitable, and thus the measurement precision is influenced.

Secondly, to great subject, the cloud of freezing fog field homogeneity test face is great, and the quantity of measuring point is very much, and the testing personnel need operate for a long time at low temperature, and artifical measuring efficiency is low, and the testing personnel expose for a long time and have the frostbite risk under the low temperature environment.

Thirdly, the LWC uniformity test usually needs to be repeated for a plurality of times, a large amount of time is spent for manually removing the ice layer between the two tests, and the collection efficiency of the supercooled water drops on the front edge of the grating is seriously influenced if the ice layer is not completely removed, so that the accuracy of the uniformity evaluation of the frozen fog field is seriously influenced.

Because the icing grid and the measurement method in the prior art can not accurately and efficiently evaluate the uniformity of the icing wind tunnel cloud and mist field, the technical field of icing wind tunnel measurement always needs to measure the icing thickness with higher efficiency and higher precision and evaluate the uniformity of the cloud and mist field.

Disclosure of Invention

The invention aims to provide an icing cloud and mist measuring device and an icing cloud and mist measuring method, aiming at solving the technical problems of poor measuring precision and low measuring efficiency in the prior art and the risk of frostbite caused by long-time exposure of a tester in a cold environment.

First, the present invention provides an icing cloud and mist measuring apparatus, comprising: a grille arrangement comprising: a grid frame; the transverse grid bars and the longitudinal grid bars are arranged in the grid frame in a criss-cross manner; ice sheet thickness measuring device, ice sheet thickness measuring device includes: an imaging device arranged to image the ice layer at designated measuring points on the transverse and longitudinal grid bars from the front of the grid device to obtain an image of the ice layer and thereby measure the thickness of the ice layer in a non-contact manner.

Through freezing cloud and mist measuring equipment, the thickness of the ice layer on the grid device can be measured in a non-contact mode, on one hand, the ice layer can be prevented from being damaged, the measuring accuracy is improved, on the other hand, labor consumption can be reduced, and therefore the measuring process is more efficient and safer.

Advantageously, the ice layer thickness measuring device further comprises an indicating element arranged at an intersection of the transverse grid bars and the longitudinal grid bars, extending forward from the intersection, and comprising a scale in a forward direction, whereby the thickness of the ice layer is measured by an image of the ice layer in combination with the scale.

By means of the scales on the indicating element, the thickness of the ice layer can be directly read through the obtained image, so that the process of analyzing the thickness is greatly simplified, the efficiency is improved, and the workload is reduced.

Preferably, the ice cloud and mist measuring apparatus further comprises a control device, the imaging device comprising an illumination element and a camera element, the control device being configured to be associable with the imaging device so as to be able to manipulate the illumination element and the camera element to trigger it to image the layer of ice. The imaging device can be easily actuated by means of the control device, so that the ice layer can be imaged more clearly, in order to obtain a more sharp image, which contributes to an increased accuracy of the thickness measurement.

In some embodiments, the imaging device further comprises camera heads for mounting the illumination element and the camera element, the camera heads being symmetrically arranged on the left and right sides and/or the upper and lower sides of the grid frame. With the camera head, the imaging device can be stably disposed at a suitable location on the grill frame, thereby improving imaging efficiency and quality.

In addition, the icing cloud measuring device further comprises a deicing device, wherein the deicing device comprises an excitation device for vibrating the grid device and/or a heating device for heating the grid device.

The vibration excitation device can be used for pre-removing the large ice blocks, so that the deicing efficiency is improved. Accumulated ice on the grating device can be completely removed in a simple non-contact mode by means of the heating device, the workload is reduced, and the overall test efficiency is improved.

The invention also provides an icing fog measuring method, which comprises the following steps: arranging a grid arrangement in a test position, the grid arrangement comprising: a grid frame; the transverse grid bars and the longitudinal grid bars are arranged in the grid frame in a criss-cross manner; spraying the grille means so that it is placed in a cloud field, wherein ice accretion is on the grille means at a predetermined temperature; the ice layer at the designated measuring points on the transverse and longitudinal grid bars is imaged from the front of the grid arrangement to obtain an image of the ice layer and thereby measure the thickness of the ice layer in a non-contact manner.

The thickness of the ice layer on the grating device can be measured in a non-contact mode by imaging the ice layer at the designated measuring point, on one hand, the ice layer can be prevented from being damaged, the measuring accuracy is improved, on the other hand, the manual consumption can be reduced, and therefore the measuring process is more efficient and safer.

Preferably, at the crossing point of the transverse grid bars and the longitudinal grid bars, an indicating element is arranged extending forward from the crossing point, the indicating element comprising a scale in the forward direction, the method comprising: the thickness of the ice layer is measured by the image of the ice layer in combination with the scale.

The thickness of the ice layer is measured by combining the image with the scale of the indicating element, so that the process of analyzing the thickness can be greatly simplified, the efficiency is improved, and the workload is reduced.

Advantageously, the illumination element and the camera element are triggered by the control device to image the ice layer at the specified measuring point at a predetermined angle and distance.

The control device is used for triggering the imaging device, so that the illuminating element and the camera element can be controlled to start to work simultaneously, an ice layer image with higher definition can be obtained, and the accuracy of thickness measurement is improved.

In particular, the grid device includes a geometrically central locus, the method further comprising: and (3) calculating ice thickness deviation: calculating an ice thickness deviation at the designated measurement point by the thickness of the ice layer measured at the designated measurement point and the thickness of the ice layer measured at the geometric center position; an evaluation step: the uniformity of the cloud field is evaluated by determining whether the ice thickness deviation exceeds a predetermined threshold. The uniformity of the artificial frozen fog field (or called cloud and fog field) is evaluated by calculating the deviation of ice thickness of each measuring point on the grid and the geometric center position of the grid, and whether the current cloud and fog field meets the airplane test standard or not can be quickly and easily judged. Notably, the liquid water content deviation can be characterized by the calculated ice thickness deviation. This is advantageous because the liquid water content deviation is usually not directly measurable.

In some embodiments, the ice accretion thereon is pre-de-iced by vibrating the grid arrangement. The large ice blocks can be pre-removed by generating vibration, so that the deicing efficiency is improved.

Furthermore, after pre-deicing, the ice accretion located thereon is removed by heating (e.g. electrical heating) the grid arrangement. Accumulated ice on the grating device can be removed comprehensively in a simple non-contact mode through heating, the workload is reduced, and the overall test efficiency is improved.

Drawings

FIG. 1 schematically illustrates a perspective view of one embodiment of an ice cloud and mist measurement device according to the present disclosure;

FIG. 2 schematically illustrates a front view of the embodiment of FIG. 1 of an ice cloud measurement device according to the present invention;

fig. 3 schematically shows an embodiment of a grid arrangement of an icing cloud measuring device according to the invention, wherein the geometric centre point of the grid arrangement and the designated measuring points formed by the transverse grid bars and the longitudinal grid bars are shown;

FIG. 4 schematically illustrates one embodiment ofbase:Sub>A grille arrangement of an ice cloud measurement apparatus according to the present invention, FIG. 4A showing an enlarged view of the circled area in FIG. 4, and FIG. 4B showingbase:Sub>A cross-sectional view of section A-A in FIG. 4;

fig. 5 schematically shows an embodiment of the icing cloud measuring device according to the invention, wherein imaging means, control means, etc. are shown.

List of reference numerals

100. Icing cloud measuring equipment

110. Grid device

112. Grid framework

114. Transverse grid bar

116. Longitudinal grid bar

118. Geometric center point

120. Vibration exciter

130. Heating device

140. Indicating element

150. Image forming apparatus with a plurality of image forming units

152. Lighting element

154. Camera element

156. Camera pan-tilt

160. Synchronizer with improved synchronization

170. Control device

180. A lifting device.

Detailed Description

The present invention will be further described with reference to the following specific examples and drawings, but the scope of the present invention should not be limited thereto.

The invention mainly relates to the field of airplane tests, in particular to the technical field of icing wind tunnel measurement. In the present invention, although the description is made by taking the ground frost conditions for civil aircraft, it will be understood by those skilled in the art that the icing cloud measuring device and the icing cloud measuring method of the present invention can be applied to the occasions of frost freezing tests for various aircrafts, vehicles, ships, etc. other than civil aircraft.

Secondly, descriptions concerning orientations such as "top", "upper" and "lower" or "bottom" are all with reference to the normal state of placement of the ice cloud measurement device, i.e. the top or upper portion is physically above the lower or bottom portion. Further, referring to the drawings, "front" or "forward" refers to a direction pointing perpendicularly out of the paper, and "rear" or "rearward" refers to a direction pointing perpendicularly into the paper. In addition, "lateral" and "longitudinal" may be with respect to the ground, e.g., horizontal and vertical, but may also be with respect to a component, e.g., the frame itself, i.e., relatively horizontal and relatively vertical.

Finally, it is noted that the numerical values given in the embodiments are only examples and do not limit the scope of the present invention.

The ice cloud measurement device 100 of the present invention includes a grating arrangement 110. However, it should be noted that the ice cloud measurement method of the present invention can be performed by using the grille device 110, but is not limited to the grille device 110 having the following structure, and may be any suitable icing grille that meets the aircraft test standards.

The grill device 110 may include at least one grill frame 112. When there are a plurality of grill frames 112, the grill frames 112 may be connected together in alignment with each other, but only one grill frame 112 is preferable. Within the grid frame 112 may be disposed transverse grid bars 114 and longitudinal grid bars 116, which are staggered with respect to one another, as best shown in fig. 1-3. Advantageously, the plurality of transverse grills 114 are spaced parallel to one another, while the plurality of longitudinal grills 116 are also spaced parallel to one another.

Preferably, the plurality of transverse grate bars 114 and the plurality of longitudinal grate bars 116 are vertically staggered with respect to each other, but it is understood that a vertical distribution with slight angular deviations is also within the scope of the present invention. More preferably, the transverse grill bars 114 evenly divide the longitudinal grill bars 116 into equal parts, and the longitudinal grill bars 116 also evenly divide the transverse grill bars 114 into equal parts. In some embodiments, FIG. 3 shows the measurement point locations and numbering resulting from the interleaving of the horizontal grid bars 114 and vertical grid bars. The number of the transverse grid bars 114 is 1, 2, \8230, i.e. n (namely, 1 is less than or equal to i is less than or equal to n) in sequence from top to bottom, while the number of the longitudinal grid bars 116 is 1, 2, \8230, j.m (namely, 1 is less than or equal to j is less than or equal to m) in sequence from left to right. Thus, the measurement point on the staggered grid may be labeled (i, j). The respective numbers of the transverse grill bars 114 and the longitudinal grill bars 116 may be equal or different. In particular, the number may be odd.

For more precise positioning, the grille arrangement 110 may have a geometric center point 118. As shown in fig. 3, the geometric center point 118 may be formed by the intersection of the most central one of the plurality of longitudinal grill bars 116 and the most central one of the plurality of transverse grill bars 114 of the grill device 110. This is only preferred since the grid arrangement 110 may also have a geometrical centre point which is not a physical real point.

Before beginning the formal measurement, the ice cloud measurement method of the present invention may include a positioning step, i.e., placing the grid arrangement 110 at a test location. In some embodiments, the geometric center point 118 of the grille arrangement 110 is located on the centerline of the wind tunnel outlet when in the test position. The positioning step described above may be accomplished, for example, by adjusting the position and/or angle of the grille arrangement 110. In a preferred embodiment, the grille installation 110 is mounted on a grille mounting platform and its position is moved by the lifting device 180, but the positioning step of the ice cloud measurement method of the present invention is not limited to this.

After the positioning step, the wind tunnel may be turned on to adjust the wind speed of the test section to the test target value and to bring the test ambient temperature to the frost ice requirement, for example, below-18 degrees celsius. In addition, the water supply system, the air supply system, and the spray system may be turned on to adjust the supply water pressure, the supply air pressure, the supply water temperature, the water flow rate, etc. for the test to target parameters. In the present invention, one or more of these operation steps may be referred to as a parameter adjustment step. Since these pressures, temperatures, and flow rates should generally meet the standard specifications, which are known to those skilled in the art, they will not be described in detail herein.

After completing the adjustment of the parameters to achieve the predetermined test conditions, the ice cloud measurement method of the present invention may include spraying the grid device 110 so that it is placed in the cloud field. At a predetermined temperature, ice may thus accumulate on the grill device 110. The spray may be continued for a specified period of time to produce a layer of ice on the grating device 110, particularly on the transverse grating bars 114 and the longitudinal grating bars 116, suitable for measurement.

To facilitate the measurement, designated measurement points are usually provided at certain locations on the grid arrangement 110, mainly on the transverse grid bars 114 and the longitudinal grid bars 116, in particular at their intersections. One or more designated measurement points may be provided, preferably at a plurality of intersections, but a desired measurement point may be selected as needed.

In order to be able to measure the thickness of the ice layer accumulated on the grid arrangement 110, the ice cloud measuring method of the present invention may include a thickness measuring step of imaging the ice layer at designated measuring points on the lateral grid bars 114 and the longitudinal grid bars 116 from the front of the grid arrangement 110 to obtain an image of the ice layer and thereby measure the thickness of the ice layer in a non-contact manner. Here, "non-contact" means that measurement is performed without contact with the ice layer itself. In other words, the ice layer thickness measuring process of the present invention does not contact the ice layer, and the ice layer is prevented from being damaged by contact, for example, the ice layer is not touched by a measuring tool such as a vernier caliper. Furthermore, the ice layer thickness measurement process does not contact the grid assembly 110, for example, the longitudinal grid strips 116 or the transverse grid strips 114.

To this end, the icing cloud measuring apparatus 100 of the present invention may include an ice layer thickness measuring device, which may include an imaging device 150, the imaging device 150 being arranged to image the ice layer at designated measuring points on the lateral and longitudinal grill bars 114 and 116 from the front of the grill device 110.

Advantageously, the imaging device 150 may be arranged in front of the grid arrangement 110, but preferably not directly in front. As shown in fig. 1 and 2, the imaging devices 150 may be disposed on the left and right rims of the grid device 110, preferably symmetrically on the left and right sides thereof. The imaging devices 150 may also be disposed on the upper and lower rims of the grill device 110, preferably symmetrically on the upper and lower sides thereof. In the present invention, the image forming device 150 preferably includes at least two groups, such as four groups, but is not limited thereto, and may be a single group, for example.

In the embodiment shown in fig. 1, the imaging device 150 may also be suspended from the grid frame 112 by means of connecting elements, such as struts. In particular, the imaging device 150 is arranged to be deflected outwardly (i.e. out of the range of the grid arrangement 110) relative to the grid arrangement to minimize the interference of the imaging device 150 itself with the icing cloud test.

The imaging device 150 may include an illumination element 152 for providing illumination to the ice layer during imaging. The imaging device 150 may also include a camera element 154. In the present invention, the camera component 154 includes, but is not limited to, various types of imaging components such as a camera, a video camera, and the like. Therefore, the image of the ice layer obtained by the imaging device 150 of the present invention may include a still picture, a moving picture, a video, and the like, and is within the scope of the present invention as long as the thickness of the ice layer on the grill device 110 can be clearly displayed. Advantageously, the illumination element 152 may provide illumination while the ice layer is being imaged.

Preferably, the imaging device 150 may further include a camera platform 156 such that the illumination element 152 and the camera element 154 may be stably disposed thereon. More preferably, the camera heads 156 may be symmetrically disposed on the right and left sides and/or the upper and lower sides of the grill frame 112 (depending on the number of groups of the imaging devices 150 provided as mentioned above).

To handle the imaging process, the ice cloud fog measurement method of the present invention may further comprise triggering the illumination element 152 and the camera element 154 by the control device 170 to image the ice layer at a specified measurement point at a predetermined angle and distance, thereby obtaining a measurement of the ice layer thickness in a non-contact manner.

To this end, the control device 170 may be configured to be associated with the imaging device 150, for example. In the embodiment shown in fig. 5, the icing cloud measuring device 100 of the present invention further comprises a synchronizer 160, the illumination element 152 and the camera element 154 are directly connected to the synchronizer 160, and the control device 170 controls the synchronizer 160 to simultaneously trigger the illumination element 152 and the camera element 154 to operate.

After imaging the ice layer at the specified measurement point, the obtained picture of the ice layer may be analyzed. In order to better recognize the thickness of the ice layer, the grille arrangement 110 is preferably designed to be eye-catching, for example yellow, so as to be clearly distinguishable from the color of the frost ice itself. In addition, in order to directly read the thickness through the image of the ice layer, the relationship between the thickness of the ice layer displayed on the image obtained by the imaging device 150 and the actual thickness of the ice layer may be calibrated before the formal test. Typically, when calibration is complete, the position and angle of the imaging device 150 relative to the grid assembly 110 will not change unless recalibration is performed. For example, the dimensions of the ice layer displayed on the picture may have a fixed proportional relationship with the thickness of the ice layer measured by contact.

Preferably, however, the ice layer thickness measuring device may further include an indicating member 140. The indicator element 140 may, for example, be disposed at the longitudinal intersection of the transverse grid bars 114 and the longitudinal grid bars 116, extend forwardly from the intersection (i.e., project forwardly from the plane formed by the leading edges of the grid bars), and include a scale in the forward direction, as best shown in fig. 4B. Thus, the thickness of the ice layer can be measured in the present invention by the image of the ice layer in combination with the scale on the indicating member 140. Specifically, after an image of the ice layer is obtained, the thickness of the ice layer can be read out directly from the image by means of the scale at the ice layer, so that the thickness measurement efficiency and accuracy are greatly improved.

It will be appreciated that the analysis of the thickness of the ice layer based on the acquired image in the present invention may be performed manually by a human tester, but may also be performed automatically by software (including reading the thickness of the ice layer by means of a scale in the image, or determining the relationship between the size of the ice layer in the image and the actual thickness of the ice layer).

According to the present invention, after the thickness of the ice layer at each specified measurement point is obtained from the image, an arithmetic average may be further found as the measured value of the ice thickness at each measurement point. For example, the thickness of the ice layer at the jth column measurement point on the transverse cell i may be denoted as δ (i, j), while the thickness of the ice layer at the geometric center point 118 of the grid arrangement 110 may be denoted as δ c.

Furthermore, the ice cloud and fog measuring method of the present invention further includes an ice thickness deviation calculating step, that is, the ice thickness deviation at each designated measuring point can be calculated by the thickness of the ice layer measured at each designated measuring point and the thickness of the ice layer measured at the geometric center position. In other words, the ice thickness deviation is related to several factors, and the specific correlation may vary according to different test sites.

The calculation formula of the ice thickness deviation of the present invention can be expressed as follows:

where α (i, j) is an ice thickness deviation at the measurement point (i, j), δ (i, j) is an ice thickness at the measurement point (i, j), δ c is an ice thickness at the geometric center position of the grid, LWC (i, j) is a liquid water content at the measurement point (i, j), and LWCc is a liquid water content at the geometric center position of the grid. Due to the fact that

Is proportional to

α (i, j) therefore also characterizes the liquid water content deviation at the measurement point (i, j). This is advantageous because the liquid water content deviation is usually not directly measurable.

The icing fog cloud measurement method of the invention may further comprise an evaluation step of evaluating the uniformity of the fog cloud field by determining whether the ice thickness deviation exceeds a predetermined threshold. In some embodiments, the predetermined threshold is 20%, but other thresholds are contemplated, such as 5%, 10%, 15%, 25%, 30%, etc. For example, if | α (i, j) | (i.e., the ice thickness deviation at all the specified measurement points) is less than or equal to 20%, the uniformity of the artificial cloud field meets the test requirements; if the alpha (i, j) is greater than 20 percent (namely, the ice thickness deviation at least one specified measuring point), the uniformity of the artificial frost fog does not meet the test requirement, and the reason needs to be further analyzed.

After the measurement is completed, the icing cloud measuring apparatus 100 of the present invention may further include a deicing device for efficient deicing. The de-icing assembly may include an excitation device 120 for vibrating the grille arrangement 110. The excitation device may be disposed, for example, directly below the grid frame 112, but is not limited to this location.

Furthermore, the de-icing device may also comprise a heating device 130 for heating, in particular electrically heating, the grid arrangement 110. Preferably, the heating device 130 may be disposed on at least one of the plurality of longitudinal grill bars 116 and/or the plurality of transverse grill bars 114. For example, the heating device 130 may be an electrically heated film that is laid over the grid arrangement 110, primarily the longitudinal grid bars 116 and/or the transverse grid bars 114, as best shown in fig. 4A. Most preferably, the heating devices 130 may be disposed on the front surface (i.e., the end surface facing forward in fig. 4) and both sides (i.e., the upper and lower sides of the transverse grill bars 114 and the left and right sides of the longitudinal grill bars 116 in fig. 4) of the grill bars. It should be understood, however, that the heating device 130 of the present invention is not limited to electrical heating, but may be any device or element that achieves heating, such as a heating device 130 designed based on the principles of radiant heating, convective heating, and the like.

In the ice cloud measurement method according to the present invention, it is preferable that the excitation device 120 is first turned on to perform pre-deicing so that the main body of the ice layer is detached from the grid device 110 by vibration. After the bulk of the ice layer has fallen, the heating device 130 may be turned on to remove any accumulated ice remaining on the surface of the frozen grate bars in preparation for the next test. Therefore, the deicing device can efficiently remove ice through a combined mode of vibration and heating, and the test efficiency is greatly improved.

Finally, the icing cloud testing method according to a particular embodiment of the invention, but this is obviously merely exemplary, and one or more of the steps may be eliminated or replaced altogether. In step S1, the grid arrangement 110 is placed in the test position, and the geometric center point 118 of the grid arrangement 110 is adjusted to be located on the center line of the outlet of the wind tunnel; in the step S2, the wind tunnel is started, the wind speed of the test section is adjusted to a test target value, and the test environment temperature is enabled to meet the frost ice requirement; in step S3, a water supply system, an air supply system and a spraying system are opened, and water supply pressure, air supply pressure, water supply temperature, water flow and the like are adjusted to target parameters; in step S4, spraying is performed for a designated time so that frost ice accretion is generated on the grill device 110; in step S5, the lighting element 152 and the camera element 154 are triggered by the control device 170 to perform shooting imaging at a fixed angle and distance; in step S6, the thickness of the ice layer at each measurement point under the corresponding camera element 154 is obtained according to the image captured by the camera element 154 and by referring to the scale of the indicating element 140 (for example, in the form of a pointer), and further an arithmetic average value is obtained as the measured value of the ice thickness at each measurement point, the dimension in the thickness direction of the jth row of measurement points on the transverse unit i is recorded as δ (i, j), and the ice thickness at the geometric center position of the grid is recorded as δ c; in step S7, the icing cloud field uniformity is evaluated; in step S8, the vibration excitation device 120 is turned on to pre-deice the ice layer, and the electric heating device is turned on after the ice layer main body falls off to remove the remaining ice accumulated on the surface of the icing grid.

Although various embodiments of the present invention are described in the drawings with reference to an ice cloud measurement device and measurement method for use in ground frost testing of civil aircraft, it should be understood that embodiments within the scope of the present invention may be applied to other applications requiring measurement of ice layer thickness having similar structure and/or functionality.

The foregoing description has set forth numerous features and advantages, including various alternative embodiments, as well as details of the structure and function of the apparatus and method. The intent herein is to be exemplary and not exhaustive or limiting.

It will be obvious to those skilled in the art that various modifications may be made, especially in matters of structure, materials, elements, components, shape, size and arrangement of parts including combinations of these aspects within the principles described herein, as indicated by the broad, general meaning of the terms in which the appended claims are expressed. To the extent that such various modifications do not depart from the spirit and scope of the appended claims, they are intended to be included therein as well.

Claims (11)

1. An ice cloud measurement device, comprising:

a grille arrangement comprising:

a grid frame;

the transverse grid bars and the longitudinal grid bars are arranged in the grid frame in a criss-cross mode;

an ice layer thickness measuring device, the ice layer thickness measuring device comprising:

an imaging device arranged to image the layer of ice at designated measurement points on the transverse and longitudinal grid bars from the front of the grid device to obtain an image of the layer of ice and thereby measure the thickness of the layer of ice in a non-contact manner.

2. The ice cloud measurement device of claim 1, wherein said ice layer thickness measuring means further comprises an indicating element disposed at an intersection of said transverse grid bars and said longitudinal grid bars, extending forward from said intersection, and including a scale in a forward direction, whereby said thickness of said ice layer is measured by said image of said ice layer in conjunction with said scale.

3. The ice cloud and fog measuring device of claim 2, further comprising a control device, said imaging device comprising an illumination element and a camera element, said control device configured to be associated with said imaging device such that said illumination element and said camera element can be manipulated to trigger imaging of said layer of ice.

4. The icing cloud measurement device of claim 3, wherein said imaging means further comprises camera heads for mounting said illumination element and said camera element, said camera heads being symmetrically arranged on the left and right sides and/or on the top and bottom sides of said grid frame.

5. The ice cloud measurement device of any one of claims 1-4, further comprising a de-icing means, said de-icing means comprising an excitation means for vibrating said grid means and/or a heating means for heating said grid means.

6. An ice cloud measurement method, the method comprising:

arranging a grid arrangement in a test position, the grid arrangement comprising:

a grill frame;

the transverse grid bars and the longitudinal grid bars are arranged in the grid frame in a criss-cross mode;

spraying the grille means so that it is placed in a cloud field, wherein ice accretion is on the grille means at a predetermined temperature;

imaging the ice layer at designated measuring points on the transverse grid bars and the longitudinal grid bars from the front of the grid arrangement to obtain an image of the ice layer and thereby measure the thickness of the ice layer in a non-contact manner.

7. The ice cloud fog measuring method of claim 6, wherein an indicating element extending forward from an intersection of the transverse grid bars and the longitudinal grid bars is disposed at the intersection, the indicating element including a scale in a forward direction, the method comprising: measuring the thickness of the layer of ice from the image of the layer of ice in combination with the scale.

8. The ice cloud measurement method of claim 7, wherein the ice layer at the specified measurement point is imaged at a predetermined angle and distance by triggering an illumination element and a camera element by a control device.

9. The ice cloud measurement method of any one of claims 6-8, wherein the grid arrangement includes a geometric center point, the method further comprising:

and (3) calculating ice thickness deviation: calculating an ice thickness deviation at the designated measurement point by the thickness of the ice layer measured at the designated measurement point and the thickness of the ice layer measured at the geometric center position;

an evaluation step: evaluating the uniformity of the cloud field by determining whether the ice thickness deviation exceeds a predetermined threshold.

10. The ice cloud measurement method of any one of claims 6 to 8, wherein the accumulated ice thereon is pre-deiced by vibrating the grid arrangement.

11. The ice cloud fog measurement method of claim 10, wherein after pre-deicing, accumulated ice located thereon is removed by heating the grille means.

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