JPH07174687A - Particle analysis method utilizing laser doppler method - Google Patents

Abstract

PURPOSE:To achieve an accurate quantitative evaluation by obtaining particle information in reference to the cam angle of an injection pump from a Doppler burst signal and then synchronizing it with the injection characteristics of an injection pump. CONSTITUTION:A laser transmitter 1 travels to a desired measurement space 4 in a position where two laser beams cross each other with the drive of a motor controller 6. A Doppler burst signal obtained by each detector of a receiver 3 is processed by a processor 7 and is input to a computer 5. Also, a liquid which is compressed by an injection pump 9 by the drive of an AC motor 10, is injected into an injection space including the space 4 via an injection nozzle 8. The cam angle information of a pump 9 is detected and processed 12 by a rotary encoder 11 and input to the computer 5 and then a processing in reference to the cam angle is performed according to the Doppler burst signal, thus acquiring particle information in synchronization with the injection rate characteristics of the pump 9 as well as particle information in reference to time and achieving an accurate quantitative evaluation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser Doppler method which is used for measuring particles moving at high speed and high density such as diesel spray and used for grasping the atomization phenomenon of fluid. The present invention relates to a particle analysis method used.

[0002]

2. Description of the Related Art For example, in order to enable quantitative research on the correlation between injection, spray characteristics and combustion of a diesel engine, the relationship between the temporal characteristics of the injection and the spatiotemporal characteristics of the formed spray is required. Need to be clarified. In particular, the atomization phenomenon related to a low concentration particle group, which has a long time in the liquid splitting process, has been gradually elucidated from previous studies, but as with diesel spray, high speed,
With respect to the phenomenon of flying at a high concentration and progressing atomization in an extremely short time, there is currently no means that can be sufficiently measured.

Conventionally, in order to evaluate the spatiotemporal characteristics of such a diesel spray in real time, a phase laser Doppler velocimeter (PLDV), which is an improved version of an ordinary laser Doppler velocimeter (LDV), is used to spray. Methods for quantitatively grasping flow characteristics have been developed (WDBACHALO and MJ
HOUSER; "Phase / Doppler spray analyzer for simultan
eous measurements of drop size and velocity distri
butions ", OPTICAL ENGINEERING, Vol.23, No.5, (198
4), p.583-590). This is because a plurality of photomultiplier tubes are installed in the receiver of the optical system used in the LDV method, and the speed and particle size of the sprayed particles are obtained by simultaneously analyzing the conventional Doppler burst signal period and the phase difference that differs depending on the sphericity. It is designed so that and can be measured at the same time.

More specifically, the PLDV is shown in FIG.
2 has a laser oscillator 1 for emitting two laser beams intersecting in the measurement space 4, and a receiver 3 arranged so as to face the measurement space. For example, 3 detectors (detector 1, detector 2, detector 3)
Is provided. In the measurement space 4, the two laser beams intersect to produce the interference fringe shown in FIG. When a particle passes through this, the intersecting laser light hits the particle and is scattered, and the three detectors generate the same signal (Doppler burst) generated when the interference fringes pass by the Doppler difference frequency, as shown in FIG. Signal). The velocity of the particle is calculated from the positional relationship between the period of this Doppler burst signal and the detector.

Further, the Doppler burst signal detected by each detector has a phase shift proportional to the interval of the interference fringes, and the Doppler burst signal detected by the detector 1 and the detector 2 has a phase difference. Deviation φ _1-2 and phase difference φ of Doppler burst signal detected by detector 1 and detector 3
_1-3 are obtained by Expression 1.

[0006]

[Formula 1] φ _{1-2 (1-3)} = T _{1-2 (1-3)} / TD × 360 °

Here, T _{1-2 (1-3)} is the time between the zero crossing points of the signals of detectors 1 and 2 (detectors 1 and 3), and TD
Is Doppler time. This phase shift and grain size are
Since the correlation is as shown in FIG. 10, the particle size is directly calculated from this correlation.

A particle analyzer (PDPA-100: resolution 20 MHz, data rate 120 KHz) manufactured by AEROMETRICS is known as a device for measuring the local particle size and particle velocity using such a method. . In addition, recently, there is a device in which the data rate is improved to nearly 100 times.

[0009]

However, although the conventional particle analysis apparatus has been improved in data rate, the phenomenon that the particles fly at a high speed like diesel spray and the atomization progresses in an extremely short time is described. Was unable to completely supplement the single spray. In particular, since it was not possible to collect data synchronized with injection characteristics such as injection rate, it was extremely difficult to analyze diesel spray. In addition, in the particle analysis by the PLDV method, a non-spherical particle that has just been divided cannot be evaluated in principle.
Since there are restrictions such as the measurement range of the particle size, particle speed, and particle concentration being limited by the conditions of the selected optical system, it was impossible to detect the properties of all particles passing through the measurement space.

In order to evaluate even non-spherical particles, the device shown in FIG. 7 is used as a PLDV for measuring particle size and particle speed,
After that, as shown in FIG.
It is also conceivable to use the device shown in (1) as an LDV that measures only the particle velocity and use it properly.

When the measuring methods of the particles to be measured by the PLDV method and the LDV method are respectively outlined, as shown in FIG. 11, in the PLDV method, three Doppler burst signals are made symmetrical as shown in FIG. 9 (step 80 ), It is determined whether or not the symmetrized signal is a normal pattern in which positive and negative alternate changes (step 81). If it is not a normal signal, the measurement information is deleted (step 82), and if it is a normal signal, it is next determined whether the measured particles are spherical or non-spherical (step 83). This determination is made based on FIG. 10 based on whether or not the particle size obtained from φ _1-2 and the particle size obtained from φ _1-3 match within a predetermined range. The particle size and the particle velocity are determined and calculated (step 84), and if they do not match within a predetermined range, the measurement information is deleted (step 85).

On the other hand, in the LDV method, one Doppler burst signal obtained from any one of the three detectors is made symmetric (step 90), and the symmetrized signal normally changes in positive and negative. It is determined whether or not it is a pattern (step 91). If it is not a normal signal, the measurement information is deleted (step 92). If it is a normal signal, the particles to be measured are recognized as spherical or non-spherical particles within the measurable range, and only the particle velocity is calculated.

However, in the prior art, PLDV
Since the processing by the LDV method and the processing by the LDV method are performed separately with time lag, the PLDV function and the signal processing function based on the LDV function cannot be selectively applied to the same particle, and one particle cannot be processed. It was not possible to obtain velocity information if the particles were non-spherical particles and to obtain velocity and particle size information if they were spherical particles after determining the particle properties.

In view of the above problems, the present invention provides improved particle information for a local spray that flies at a high speed and a high concentration and progresses atomization in an extremely short time. It is an object of the present invention to provide a particle analysis method using the laser Doppler method, which enables various evaluations.

[0015]

However, the main point of the particle analysis method using the laser Doppler method is
The laser light is crossed in the measurement space where the liquid particles sprayed from the injection pump through the injection nozzle cross, and the Doppler burst signal generated when the particles pass through the measurement space is received, and the time is received from the received signal. In the particle analysis method using the laser Doppler method to obtain the particle information based on, the signal corresponding to the cam angle of the injection pump is detected, and the cam angle of the injection pump from the received Doppler burst signal. It is intended to be able to obtain particle information based on (Claim 1).

As an apparatus using such a particle analysis method, an injection pump for ejecting a fluid and a laser oscillator for emitting a laser beam so as to intersect in a predetermined space through which the fluid ejected from the injection pump passes. A receiver for receiving a Doppler burst signal generated from the predetermined space, a detector for detecting a signal corresponding to the cam angle of the injection pump in the first period, and a first process for processing the signal from the receiver with reference to time. Means and second processing means for processing the signal from the receiver with the cam angle of the injection pump as a reference are conceivable.

Further, in order to selectively apply the functions of the LDV method and the PLDV method to the same particle to be measured, laser light is crossed in a measurement space through which the particle to be measured passes, and the laser light is generated from the same particle passing through the measurement space. The Doppler burst signal is received by at least three detectors, it is determined whether the received Doppler burst signal has a predetermined pattern, and when it is determined that the Doppler burst signal has the predetermined pattern, the measured object is measured. It is determined whether or not the particle size of the particles can be measured, and if the particle size is measurable, the particle size and particle speed are calculated by distinguishing the particles to be measured as spherical, and the particle size is not measurable. If the particle to be measured is determined to be non-spherical and only the particle velocity is calculated, and if the Doppler burst signal does not have the predetermined pattern, the particle to be measured is spherical or other than non-spherical. It may be determined to be in state (claim 2). In this case, spherical, non-spherical, by marking the measured particles identified in other states,
It is desirable to store together with the information corresponding to the particles to be measured (claim 3).

[0018]

Therefore, according to the invention described in claim 1, it is possible to obtain the particle information based on the time and the particle information based on the cam angle of the injection pump from the received Doppler burst signal. In addition to the conventional particle information based only on time in FIG. 3A, particle information in time series synchronized with the injection rate characteristic shown in FIG.
(C)) is obtained. In particular, in the case of intermittent spraying, such as diesel spraying, in which high speed flight is performed and atomization proceeds in an extremely short time, the process of atomization can be grasped only by synchronizing with the injection characteristics such as the injection rate.

According to the second aspect of the present invention, spherical, non-spherical, and other (particle diameters and particle velocities outside the measurement range, or high density particle groups such as liquid columns and semi-liquid particle groups) 3
Since one of the two particle states is discriminated for the same particle, there is no need to separately perform the measurement based on the PLDV method and the LDV method under the same injection conditions. When separately measured as in the conventional case, as shown in FIG. 12, the measurement result (b) based on the LDV method and the measurement result (c) based on the PLDV method are overlapped to obtain the result (d). However, in the injection pump that repeats the injection periodically, the same spray state is not formed each time the injection is performed, so even if the measured data based on the PLDV method and the LDV method are queried, it is completely It will not be possible to overlap. On the other hand, according to the present invention, since the PLDV function and the LDV function can be selectively applied to the same particle, the work of inquiring is unnecessary and the result corresponding to (d) can be directly obtained. ,
Inappropriate evaluation can be eliminated.

Further, according to the invention described in claim 3, after determining which one of the above-mentioned three states a certain particle has, each of them is marked and stored together with the information corresponding to the particle to be measured. Therefore, for example, by displaying the marking information together with the particle information of the particles to be measured and the like, the distribution of each particle state can be known, and the atomization process can be more accurately grasped.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an improved version of a phase Doppler particle analyzer (PDPA-100) manufactured by AEROMETORICS of the United States using the phase laser Doppler method. This particle analyzer emits two laser beams. A laser transmitter 1 and a receiver 3 having therein three detectors (detector 1, detector 2, detector 3) 2 arranged in parallel at a predetermined interval are arranged so as to face the measurement space 4. And receiver 3
Is fixed at a position rotated by, for example, 30 ° about the measurement space 4 from the extension of the axis of the laser oscillator 1. The laser oscillator 1 is driven and controlled by the motor controller 6 based on a control signal from the computer 5, and the position where the two laser beams intersect can be moved to a desired measurement space 4. The signals obtained by the detectors of the receiver 3 are processed by the processor 7 and input to the computer 5.

The liquid compressed by the jet pump 9 is jetted into the spray space including the measurement space 4 via the jet nozzle 8. The injection pump 9 is driven by, for example, an AC motor 10, and cam angle information of the injection pump 9 is detected by the rotary encoder 11 and processed by the processor 12 before being input to the computer 5.

Here, the particle analyzer (PDPA-100)
Resolution is 20MHz, data rate is 120KH
z, and the resolution of the rotary encoder 11 is 2000
Guaranteed 0.1 ° / pulse up to rotation / min.

In this embodiment, a BOSCH-VE type injection pump 9 having the specifications shown in Table 1 and a pilot injector 13 are combined, and a DL is used as a nozzle 8.
The LA-P type is used. The VE type injection pump is known per se and its description is omitted. However, as shown in FIG. 2A, the pilot injector 13 is face-cut at a position facing the nozzle 8 via the nozzle spring 14. The dodge plunger 15 is provided, and pilot injection is enabled by adjusting the pressure applied to the dodge plunger 15, and the valve opening pressure at the time of main injection is made higher than that at the time of pilot injection. In the figure, 16 is a fuel introduction path, and 17 is a path for leaking fuel. Further, the nozzle 8 is 10 ° as shown in FIG.
5 nozzle holes (diameter -0.2
Practical non-axisymmetric nozzle with 5 mm).

[0026]

[Table 1]

[0027]

[Table 2]

In the above experimental apparatus, if the cam angle information is not taken into consideration, it is possible to obtain the particle information within the elapsed time by performing the data processing based on only the same time as the conventional one, and the cam angle information can be obtained. By performing the data processing based on the information, it is possible to acquire the particle information in synchronization with the rotation of the injection pump, that is, in synchronization with the injection rate characteristic. Measurement space 4
Is set at a position where the axial distance Lx from the injection nozzle tip is 50 mm and the radial distance Lr is 0 mm, and when the particle diameter information based on time is compared with the particle diameter information based on the cam angle, According to the particle size information based on the conventional time reference, as shown in FIG. 3A, one spray cannot be finely supplemented due to the low data rate, but the processing is performed based on the cam angle reference. Particle size information (Fig. 3 (c))
Indicates that particle size information synchronized with the injection rate (dQ / dθ) characteristics shown in FIG. 3 (b) is obtained, and that spherical particles are not formed at the initial stage of pilot injection and main injection (non-spherical particles or measurement Existence of oversized particles beyond the range)
Was confirmed.

In the figure, Np is the pump speed, Q is the injection amount, D _DPS is the seat diameter of the dodge plunger, and L _DPL is the maximum lift amount of the dodge plunger.

By obtaining such particle size information of the local space in synchronism with the cam angle, it can be applied to various spray analysis. For example, the sheet diameter D of the dodge plunger.
_When the local particle characteristics of the spray are measured using three _types of pilot injectors (Ip-1, 2, 3) in which _DPs are exchanged and the pilot injection amount is changed, the characteristics shown in FIG. 4 are obtained. This is 20 for the injection rate shown in (a).
It shows a particle size (D1) distribution in which measured particles obtained by zero injections are simultaneously displayed on the basis of a cam angle.
(F) shows that the position of the measurement space 4 is changed. From this experimental data, the distribution of coarse particles tends to concentrate in a certain time from the main spray as IP-3, which has a larger overtaking effect between spray groups, and coalesces particles when the main spray group overtakes the pilot spray group. It can be seen that is popular. It can also be seen that this phenomenon is particularly remarkable near the outlet of the injection nozzle ((b), (e)).

A short distance (Lx =
25 mm), the D ₃₂ (√ (D ₁ ³ ) / √ (D ₁ ² )) distribution of the local spray from the spray center to the outer circumference was measured,
It becomes like FIG. From this result, it can be seen that the particle size becomes smoother and finer as the Ip-3 specification in which the penetration of the main spray is strengthened. In fact, Ip
Since the favorable combustion state can be obtained in the -3 specification spray state, it becomes possible to quantitatively evaluate the relationship between the combustion state and the spray state.

As described above, by adding the cam angle information to the conventional time-based particle information, it is possible to quantitatively grasp the relationship between the injection characteristic, the spray characteristic, and the combustion characteristic.

An example of processing of the computer 5 for identifying the particle properties using the measuring apparatus of FIG. 1 is shown as a flow chart in FIG. 6, which will be described below. 9 and the Doppler burst signal detected by the detector 1, the detector 2, and the detector 3) and the cam angle signal detected by the rotary encoder 11 are input (step 50), and the three Doppler burst signals are symmetrized. A waveform signal indicated by is formed (step 52).

Next, it is determined whether the symmetric Doppler burst signal is normal (step 54). This determination processing may use any one of the Doppler burst signals, and determines whether or not the symmetrized Doppler burst signal is normal depending on whether or not the polarity is inverted at a substantially constant cycle. If particles or the like that exceed the measurement allowable range pass through, the cycle of polarity inversion may be disturbed, and in that case, it is determined to be abnormal (NO). In other words, in this step, with measurable spherical particles and non-spherical particles,
The process of distinguishing from other particles is performed, and the one determined to be abnormal is determined to be a high-concentration particle group such as a particle size outside the measurement range, a particle speed, or a liquid column. (Step 56).

If it is determined in step 54 that the particles are normal, the particles to be measured are spherical or non-spherical, and it is next determined which one of them is (step 58).
As described above, this determination process is performed by the detector 1 and the detector 3 and the phase shift φ _1-2 of the Doppler burst signal detected by the detector 1 and the detector 2 from the three Doppler burst signals. The phase shift φ _1-3 of the obtained Doppler burst signal is obtained by Equation 1, and the particle diameter obtained in φ _1-2 and the particle diameter obtained in φ _1-3 are compared from the correlation shown in FIG. If they match within a predetermined range, it is determined to be spherical (step 60), and if they are not the same, it is determined to be non-spherical (step 62).

Those which are determined to be spherical are PLD
The processing as the V function is performed, and the particle diameter and the particle speed are calculated (step 64). In addition, if it is determined to be non-spherical, LD
The processing as the V function is performed and only the grain speed is calculated (step 66).

The above-mentioned processes are processes for classifying the particles to be measured into non-spherical particles, spherical particles, and other states, and in the following, a process for evaluating this is performed. That is, the particles to be measured, which are determined to be spherical, are marked to identify that they are spherical (for example, correspond to ●), and this information is used in Step 6 above.
In order to identify the non-spherical particles to be measured, which are stored together with the particle information of the particle diameter and the particle speed obtained in step 4, the time, and the cam angle information (step 68) and which are determined to be non-spherical. Marking (corresponding to ○, for example), and the particle information of the particle speed obtained in step 66, time,
It is stored together with the cam angle information (step 70). Also,
Particles outside the measurement range, particle speed, or a high concentration particle group such as a liquid column is determined, and the measured particles are marked to identify them (for example, correspond to /),
This information is stored together with time and cam angle information (step 72).

Thereafter, the information stored in steps 68, 70 and 72 is simultaneously displayed on a display or the like for simultaneous evaluation (step 74).

From the above processing, no matter what the particle state of the non-measured particles is, the state can be identified by one measurement and the information corresponding to the particle state can be obtained. If the obtained measurement results are simultaneously displayed with the cam angle as a reference, the particle velocity distribution corresponding to FIG.
The particle size (D1) distribution shown in (e) is directly obtained.

As a result of such processing being possible, the proportions of the three regions (spherical, non-spherical, and other) of the particles are compared with the injection rate characteristics of FIG. 12 (a) and the combustion characteristics related to smoke and the like. The relationship can be evaluated in a simultaneous series, and it becomes possible to quantitatively evaluate the atomization process or state of the liquid jet.

In the above processing, PL for the same particles
Since the processing of the DV function and the LDV function is appropriately selected by the Doppler burst signal, the measurement is performed under the same fringe setting condition (the number of fringes, the fringe interval, etc.). Therefore, in order to obtain information corresponding to FIG. 12D, the fringe spacing of the optical system used in this experiment,
Due to the limitation of the resolution of the device, only particle information of about 80 m / s or less can be obtained. This has a resolution of 20
It is constant at MHz, and FIG. 12B shows particle information when the fringe interval is increased to increase the velocity measurement range (when the crossing angle of the laser light is narrowed), while FIG. Since c) is the particle information when the fringe interval is narrowed so that even small particles can be measured, if these pieces of information are superposed separately, it becomes as shown in FIG. 12 (d). This is because the fringe setting condition must be one condition in order to be able to select the processing of the LDV function. But,
This problem can be easily solved by increasing the resolution of the device. For example, if the device resolution is doubled to 40 MHz, the maximum speed is doubled from 80 m / s to 160 m / s.
Can be measured up to. Thus, it is easy to increase the resolution to more than twice that of the present experimental apparatus by using a commercially available processor.

[0042]

As described above, according to the first aspect of the invention, the particle information based on time and the particle information based on the cam angle of the injection pump are obtained from the Doppler burst signal. The particle information can be synchronized with the injection characteristics such as the injection rate of the injection pump, and accurate quantitative evaluation can be performed.

According to the second aspect of the present invention, it is possible to selectively obtain particle information based on the PLDV function and particle information based on the LDV function for the same particle. It is possible to determine whether the particle pattern is spherical or other, and it is possible to accurately obtain particle information for each particle. That is, if the particles are non-spherical particles, velocity information can be obtained, and if the particles are spherical particles, velocity and particle size information can be obtained.

Further, according to the third aspect of the invention, after determining which of the three particle properties the detected particle has, each is marked and stored together with the information corresponding to the measured particle. Therefore, if the display process is performed based on the marking information and the particle information, it is possible to obtain clearer information about the local spray such as the distribution of the characteristics of each particle, and perform an accurate quantitative evaluation. be able to.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a particle analysis apparatus using a particle analysis method using a laser Doppler method of the present invention.

2 (a) is a diagram showing an example of an injector used in the particle analyzer shown in FIG. 1, and FIG. 2 (b) is a diagram showing an example of a nozzle attached to the injector.

3 shows the results obtained by the apparatus of FIG. 1, (a) shows the result of data processing based on time, (b) shows the injection rate characteristics, (c) ) Indicates the result of data processing based on the cam angle.

FIG. 4 is a diagram showing three types of injectors (IP-1, IP-2, which have different sheet diameters of the dodge plunger).
It is a figure which shows the particle size distribution which synchronized with the injection rate obtained using IP-3), (a) is a diagram which shows an injection rate characteristic,
In (b), the measurement space is Lx = 25 mm, Lr = 2.5 mm
Shows the particle size distribution when, and (c) shows that the measurement space is Lx = 2.
The particle size distribution when 5 mm and Lr = 7.5 mm is shown,
In (d), the measurement space is Lx = 25 mm, Lr = 12.5 m
The particle size distribution when m is shown, (e) shows that the measurement space is Lx =
The particle size distribution when 50 mm and Lr = 2.5 mm is shown,
In (f), the measurement space is Lx = 75 mm, Lr = 2.5 mm
The particle size distribution at the time of is shown.

FIG. 5 is a diagram showing three types of injectors (IP-1, IP-2, which have different sheet diameters of the dodge plunger).
For IP-3), the D ₃₂ distribution obtained by shifting the measurement space Lx = 25 mm and Lr in the radial direction of the nozzle from the spray center is shown.

FIG. 6 is a flowchart showing an example of a particle analysis method according to the inventions of claims 2 and 3.

FIG. 7 is a phase type laser Doppler velocity meter (PL).
It is explanatory drawing which shows the basic composition of DV).

8 shows interference fringes obtained when particles to be measured are captured using the phase laser Doppler velocimeter (PLDV) shown in FIG.

9 shows a symmetric signal of the Doppler burst signal obtained with the three detectors shown in FIG. 7.

FIG. 10 is a diagram showing a correlation between a phase shift and a particle size.

FIG. 11 is a flowchart illustrating a conventional PLDV method and LDV method.

FIG. 12 (a) shows an injection rate characteristic, (b) shows a particle velocity distribution obtained based on the LDV function, and (c).
Indicates the particle velocity distribution obtained based on the PLDV function,
(D) shows the figure which combined (b) and (c), and (e) shows the particle size distribution obtained based on the PLDV function.

[Explanation of symbols]

 1 Laser Transmitter 2 Detector 3 Receiver 4 Measurement Space 5 Computer 8 Nozzle 9 Injection Pump 11 Rotary Encoder 7, 12 Processor

Claims (3)

[Claims] 1. A laser beam is crossed in a measurement space in which liquid particles sprayed from an injection pump through an injection nozzle pass, and a Doppler burst signal generated when the liquid particles pass through the measurement space is received, In the particle analysis method using the laser Doppler method to obtain time-based particle information from the received signal, the signal corresponding to the cam angle of the injection pump is detected, and the received Doppler burst signal The particle analysis method using the laser Doppler method is characterized in that the particle information based on the cam angle of the injection pump can be obtained from the above. 2. A laser beam is crossed in a measurement space through which a particle to be measured passes, a Doppler burst signal generated from the same particle passing through the measurement space is received by at least three detectors, and the received Doppler burst is received. While determining whether the signal has a predetermined pattern,
When it is determined that it has the predetermined pattern, it is determined whether the particle size of the measured particles can be measured, and when the particle size can be measured, the measured particles are determined to be spherical. Particle size and particle speed are calculated, and if the particle size is not measurable, the particle to be measured is determined to be non-spherical and only particle speed is calculated, and the Doppler burst signal does not have the predetermined pattern. In this case, a particle analysis method utilizing a laser Doppler method for determining that the particles to be measured are in a state other than spherical or non-spherical. 3. A particle analysis using a laser Doppler method according to claim 2, wherein the particles to be measured which are discriminated into spherical, non-spherical and other states are marked and stored together with information corresponding to the particles to be measured. Method.