Научная статья на тему 'Using spectroscopy of the near-infrared techniques to detection the gas'

Using spectroscopy of the near-infrared techniques to detection the gas Текст научной статьи по специальности «Физика»

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ДіОДНі ЛАЗЕРИ / БЛИЖНіЙ іНФРАЧЕРВОНИЙ / ПОГЛИНННЯ МЕТАНУ / ВИЯВЛЕННЯ / СПЕКТРОСКОПіЯ / KEYWORD: DIODE LASERS / NEAR-INFRARED / ABSORBS / METHANE / DETECTION / SPECTROSCOPIC

Аннотация научной статьи по физике, автор научной работы — Haider Ali Muse

Ближня інфрачервона спектроскопія є спектроскопічним методом, який використовує ближню інфрачервону область електромагнітного спектра. У цій статті ми покажемо, як виявити газ метану за допомогою ближньої інфрачервоної радіації з різним діапазоном довжин хвиль (від 800 нмλ до 950 нмλ). Найбільше значення було отримано в межах довжин хвиль 850 нмλ.Nеаr-

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infrared spectroscopy is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum. In this paper we will explain the methane detector by using near-infrared radiation with different wavelengths ranges (800nmλ to 950nmλ). The results, that have been obtained, had the greatest value within the wavelength 850λnm.

Текст научной работы на тему «Using spectroscopy of the near-infrared techniques to detection the gas»

Технічні науки

Scientific Journal «ScienceRise» №4/2(4)2014

Technical Station. Applied Mechanics and Materials, 97-98, 498-502. doi: 10.4028/www.scientific.net/amm.97-98.498

2. Liu, R., Whiteing, A., Koh, A. (2013). Challenging

established rules for train control through a fault tolerance approach: applications at a classic railway junction.

Proceedings of the Institution of Mechanical Engineers, Part F, 227 (6), 685-692. doi: 10.1177/0954409713496988

3. Eaton, J., Yang, Sh. (2014). Dynamic railway junction rescheduling using population based ant colony optimization. 14th UK Workshop on Computational Intelligence (UKCI). doi: 10.1109/ukci.2014.6930174

4. Hammadi, S., Ksouri, M. (2013). Optimization of Traffic at a Railway Junction: Scheduling Approaches Based on Timed Petri Nets. Multimodal Transport Systems, 199-251. doi: 10.1002/9781118577202.ch5

5. Ho, T. K., Yeung, T. H. (2010). Railway junction conflict resolution by genetic algorithm. Electronics Let-

ters, 36 (8), 771-772. . doi: 10.1049/el:20000570

6. Bernhard, K. A. (1953). Normyrovanyya razmerov dvyzhenyya peredatochnykh poezdov v zheleznodorozhnykh uzlakh. Tekhnyka zheleznykh doroh, 4, 21-25.

7. Pervozvanskyy, A. A. (1973). Matematycheskye modely v upravlenyy proyzvodstvom. Nauka, 615.

8. Habasov, R. F., Kyryllova, F. M. (1981). Metody optymyzatsyy. BHU, 350.

9. Balaka, Ye. I., Zorina, O. I., Kolesnykova, N. M., Pysarevs'kyy, I. M. (2005). Otsinka ekonomichnoyi dotsil'nosti investytsiy v innovatsiyni proekty na transporti. UkrDAZ, 210.

10. Syhorskyy, V. (1975). Matematycheskyy apparat inzhenera. Transport, 768.

Рекомендовано до публікації д-р техн. наук Огар О. М.

Дата надходження рукопису 31.10.2014

Рибалка Юлія Віталіївна, студент, кафедра управління експлуатаційною роботою, Українська державна академія залізничного транспорту, пл. Фейєрбаха, 7, м. Харків, 61050 Е-mail: vulva.rvbalka.92@mail.ru.

Сіконенко Григорій Михайлович, кандидат технічних наук, доцент, кафедра управління експлуатаційною роботою, Українська державна академія залізничного транспорту, пл. Фейєрбаха, 7, м. Харків, 61050 Е-mail: gregsik79@gmail.com

UDC: 621.373.826

DOI: 10.15587/2313-8416.2014.29615

USING SPECTROSCOPY OF THE NEAR-INFRARED TECHNIQUES TO DETECTION THE GAS

© Haider Ali Muse

Ыеаг-infrared spectroscopy is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum. In this paper we will explain the methane detector by using near-infrared radiation with different wavelengths ranges (800nmX to 950nmX) . The results, that have been obtained, had the greatest value within the wavelength 850Xnm.

Keyword: diode lasers, near-infrared, absorbs, methane, detection , spectroscopic.

Ближня інфрачервона спектроскопія є спектроскопічним методом, який використовує ближню інфрачервону область електромагнітного спектра. У цій статті ми покажемо, як виявити газ метану за допомогою ближньої інфрачервоної радіації з різним діапазоном довжин хвиль (від 800 нмХ до 950 нмХ). Найбільше значення було отримано в межах довжин хвиль 850 нмХ.

Ключові слова: діодні лазери, ближній інфрачервоний, поглинння метану, виявлення, спектроскопія.

1. Introduction

Due to the important role of spectroscopy of the laser and found immediate application in various fields , one of these fields is the detection and identification . In this research we will explain methane detection by using near-infrared . Methane is a chemical compound with the chemical formula CH4 . It is the simplest alkane, the main component of natural gas, and probably the most abundant organic compound on earth [1]. Methane is the main component of coal mine gas and natural gas, and it is closely connected with the people’s daily activities and life. Since methane gas is inflammable and explosive, it is important to accurately detect the concentration of methane gas. All this made us think to design of this device to detect methane using Near-infrared. Near-

infrared spectroscopy (NIRS) is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum (from about 800 nm to 2500 nm) [2]. Nearinfrared spectroscopy is one of the most common spectroscopic techniques used by organic and inorganic chemists. Simply, it is the absorption measurement of different IR frequencies by a sample positioned in the path of an IR beam. The main goal of IR spectroscopic analysis is to determine the chemical functional groups in the sample. Different functional groups absorb characteristic frequencies of IR radiation. Using various sampling accessories, IR spectrometers can accept a wide range of sample types such as gases, liquids, and solids. Thus, IR spectroscopy is an important and popular tool for structural elucidation and compound identification.

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2. Literature review

Methane sensors are based on various detection principles, such as catalytic combustion [3], metal-oxide-semiconductor (MOS) resistance [4], NDIR absorption spectroscopy [5, 6]. Our system consist of signal transmission unit , it is near-infrared radiation diodes its function emission near infrared waves at different wavelengths ranging from (808 nm X,850 nm X, 880 nm X, 940 nm X, 950 nm X). When we start emitting nearinfrared to the tube which containing methane, the methane will absorb part of the radiation energy passing through This occurs because of Infrared radiation contains a wide spectral content , the stretching and bending of the covalent bonds in gas molecules and this radiation interacts with gas has the same frequency as the gas molecule’s (natural frequency) the gas will absorbs some of the energy passing radiations . This vibration results in a rise in the temperature of the gas molecules. The temperature increases in proportion to gas concentration. On the other hand, the radiation absorbed by the gas molecules at the particular wavelength will cause a decrease in the original source strength. This radiation energy decrease can be detected as a signal by using photo diode which detect the quantum interaction between incident photons and semiconductor material and convert electromagnetic radiation energy changes into electrical signals . Amplification unit , in this unit is amplify the small signal which supplied by fiber optic into suitable (large signal) for read it with using display unit (Digital display) . Currently considered infrared rays with a wavelength of 1000nmX to 1550nmX is more common in the detection of methane and after the search we did not find the use of infrared with a wavelength of 700 nmX to 900 nmX , As is well known that the infrared energy in 850 nmX is large compared with the infrared energy with a wavelength of (1000nmX to 1550 nmX ) which provides an opportunity to use this device to detect on a larger scale and large distances .

3. Experimental

Infrared (IR) spectroscopy is one of the most common spectroscopic techniques, it is the absorption measurement of different IR frequencies by a sample positioned in the path of an IR beam. IR spectrometers can accept a wide range of sample types such as gases. Thus, IR spectroscopy is an important and popular tool for structural elucidation and compound identification. To illustrate the process of absorption of radiation energy by the gas The Beer-Lambert law expresses the fractional transmitted intensity of the optical wave with wave number through a path of L with an absorption coefficient. The transmission of monochromatic radiation at frequency v through a uniform medium of length L (cm) (Fig.1) is given by the Beer-Lambert relation

Tv=(It/l0)=xp(-cO (1)

where It and I0 are the transmitted and incident laser intensities, respectively, and av represents the spectral absorbance.

Fig. 1. Schematic of typical absorption measurements

For an isolated transition,

av = PXabs S(T) 4>vL (2)

where P is total gas pressure, %abs is the mole fraction of the absorbing species, T (K) is gas temperature, S (cm' 2/atm) and ®v (cm) are the line strength and lineshape function for the absorption feature [7].

The absorption rate depends on the (Absorption coefficient) it is defined by the position, strength, and shape of a spectral line. The determination of the absorption coefficient a of one absorption line of methane allows us to evaluate the feasibility of the proposed detection process. It can be expressed by:

a(v)=kP 0(v—v0) (3)

where v is the wave number (in cm-1), kP the intrinsic intensity of the absorption line (in cm-2/atm),and Ф(с ) the line shape function.

The intrinsic intensity kP is expressed as a function of the line intensity kN (cm-1/molecule cm-2) with the relationship

kP=kN Nl(T0/T)(1/P0) (4)

where P0=1 atm, T0=2.6868*1019 molecule/cm3 is the Lochsmidt number or the volume density under reference conditions.

The integral of the line shape distribution is normalized to unity

да

J ф(у)ёу = 1 (5)

—да

The line shape function Ф^) describes the effects of line broadening as a function of the pressure. At low pressure, the speed of the individual molecules is proportional to the square root of the temperature and the mass of the molecules. A photon which interacts with a given molecules has an apparent energy depending on the speed of the molecules, because of the Doppler shift. Ф(с )can therefore be described by a Gaussian distribution in low-pressure regimes (P<0.02atm). At high pressure (P>0.1atm), collisions of the molecules are dominant and lead to a Lorentzian distribution of the line shape. At intermediate pressures, a Voigt profile is normally used to describe ФМ Thus ,at atmospheric pressure , the main factor contributing to broadening of the absorption line is due to the collisions between the gas molecules, and Ф^ ) is completely determined with a Lorentzian profile with its full width at half maximum(FWHM) yL . The Lorentzian distribution is expressed by

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®L(v-Vo)=1/n * yL/((v-V0)2+y2l) ...(6)

and

Ф(±^)=1/гс * 1/2yL=ФL(0)/2 ...(7)

yL is related to pressure and temperature through the following relation:

=rLo Pa-S- (8)

where P0 and T0 are, respectively, the reference pressure and temperature, yL0is the FWHM under reference conditions [8]. At atmospheric pressure, the relative variation of yL is about 10 % between -10oCand +60oC, and a broader tuning range for the laser is not necessary. The absorption line strengths for CH4 at a reference temperature T0 of 296 K are tabulated in high resolution transmission molecular absorption database [9]. The temperature dependence of the intrinsic intensity or line strength, for a given transition (kP at transition i is generally expressed as S) can be expressed by:

S (T) = s(T0) (T )x

_1 (9)

x exp [_ *f- (t _ T- )][il _ exp ((p.)] f1 _ exp (_TT)]

where S (T0) is the line strength at reference temperature (usually T0=296 K), Q (T) the partition function of the absorbing molecule [10] , h(J s) Planck’s constant, c (cm/s) the speed of light, k (J/K) Boltzmann’s constant, E”(cm-1) the lower state energy and v0 (cm-1) the line center frequency of the transition .

The experimental conditions (room temperature, 1 bar of relative pressure), At our pressure and temperature conditions, the effect of thermal broadening is negligible. Therefore, only broadening due to collisional effects will be taken into account. Thus, the line shape function of the individual transitions will be Lorentzian [11]. To achieve high detection sensitivity, it is desirable to use as strong an absorption line as possible. And that the radiation used in the experiment is near-infrared at different wavelengths (808 nm! , 850 nm! , 880 nm! , 940 nm! , 950 nm!) . Laser diode (emitting diode) has been used as a source of infrared (LL-503 IRT2E-2AC , TSAL 5100, SFH484-2, HIRB5-43G-D, QED 222 )* laser diode was applied as the light source and operated under threshold level functioning as a LED[12]. The characteristics of the laser diodes are as follows: the wavelength range is (800 nm!-950 nm!), the current threshold at 25 Co is 13 mA, the temperature tuning rate is 0.1 nm /Co, and the current tuning rate is

0.01nm/mA. (Fig. 2) shows a diagram of a preferred embodiment of the methane detection system based upon laser diodes with the deferent frequencies.

The near-infrared laser beam is transmitted through the tube containing methane. Initially the experiment is carried without methane is then re-trial in the same conditions, but with methane to identified the amount of energy that has been absorbed and knowing the value of the response for each wavelength nearinfrared radiation . When we begins emitting near-

infrared from the transmitter unit (IR diode) through the tube which containing methane the methane will absorb part of the radiation energy passing through , this occurs because of Infrared radiation contains a wide spectral content, all the atoms in molecules are in continuous vibration with respect to each other.

detection amplification-

IP

display

transmitter 1R diode

rays emitted LH4 gas 11 4 power supply

l«MV 1 v ,l- 1 «.і. V V. V |VW» V .. VwV . vI §♦№ I ''1 4iiV> ’1 f' *' 1 'У* ■ і ■ У #^1 ■' 1 r * 1 ■ ■ j

1 ПІ in [ 1 input gas °U(pUtH J 1

Fig. 2. Diagram of a preferred embodiment of the methane detection system

The stretching and bending of the covalent bonds in gas molecules have a certain frequency which is called (natural frequency) , when the frequency of a specific vibration is equal to the frequency of the IR radiation directed on the molecule the radiation will interacts with the gas that has the same frequency as the gas molecule’s , so the gas will absorbs some of the energy passing radiations . As the gas molecules absorb this radiation, the molecules gain energy and vibrate more vigorously. This vibration results in a rise in the temperature of the gas molecules.

4. The Results of the experiment

The Fig. 3 and the Table 1 indicates that the amount of energy lost to near-infrared ray when passing through the methane were recorded and displayed on the computer.

Table 1

Respond to infrared with and wjthout Methane

wavelengths without gas (mV) With gas (mV)

800nm! 67 64

850nm! 50 32

880nm! 50 42

940nm! 84 82

950nm! 26 24

Fig. 3. Chart of the absorption rate of methane for the various wavelengths

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The chart showing the highest value of the absorption was in the wavelengths 850 nm X range.

Optical depth of a gas medium between points s1 and s2 is defined as

S2

tv (S2; S1) = I kv (S)ds (10)

S1

Where kv is the absorption coefficient of the gas.

kv= S fv - Vo) (11)

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where S in the line intensity and f is the line profile:

The optical depth is unitless.

Also the IR energy absorption is directly proportional to the molecular structure of the hydrocarbon (in addition to the concentration of the hydrocarbon present) . The received signal (optical beam) is converted to an electrical current via a photodiode and amplified by a pre-amplifier. An electronic circuit receives the signal coming from the amplifier and processes it.

Finally, the data output of the processing circuit is acquired and processed digitally using a Voltmeters . It should be noted that the detected laser signal consists of a potentially small intensity variation caused by methane gas absorption superimposed on a much larger intensity variation caused by laser power increasing with current.

5. Conclusion

Capturing and using methane can offer both opportunities to generate new sources of clean energy and mitigate global climate change. Also methane is an efficient energy source. To access the energy from methane, people burn it. It is a preferred energy source, because when it is burned, it does not create much CO2 . The advantages of using infrared radiation to detection the methane is remote detection capability, safety in a hazardous environment , and improved sensitivity leading to better capability for the detection, also it is simple, low-cost, multiple sensor strands , loops that save size, have increased reliability and field-service lifetime. In this research we were able to detect methane using near-infrared within the range of 850 nmX, where the wavelength is characterized by high powered Compare wavelengths 1230 nmX -1550 nmX , which is common in the detection of gases and which provides us the possibility of detection of the largest ranges. In General we can say that this kind of devices falls under the heading of “gas monitoring equipment”, this equipment can simply detect a variety of gases in a more profound way .We can say that the importance of this device or

any device that uses spectroscopy to detect gases can't be ignored within the research and scientific studies.

References

1. Carbon Dioxide. Methane Rise Sharply in 2007 [Electronic resource] / Available at: Noaanews.noaa.gov (Last accessed: 2008-04-23).

2. Byrnes. J. Unexploded Ordnance Detection and Mitigation [Text] / J. Byrnes. - Springer. 2009. - P. 21-22.

3. Takamoto, M. An optical lattice clock [Text] / M. Takamoto, F. L. Hong. R. Higashi. H. Katori // Nature. -

2005. - Vol. 435. Issue 7040. - P. 321-324.

4. Lee. J. Time-of-flight measurement with femtosecond light pulses [Text] / J. Lee. Y.-J. Kim. K. Lee. S. Lee.

S.-W. Kim // Nature Photonics. - 2010. - Vol. 4. Issue 10. -P. 716-720. doi: 10.1038/nphoton.2010.175

5. Steinmetz. T. Laser frequency combs for astronomical observations [Text] / T. Steinmetz. T. Wilken. C. Araujo-Hauck, R. Holzwarth, T. W. Hansch, L. Pasquini, A. Manescau., S. D’Odorico, M. T. Murphy, T. Kentischer, W. Schmidt, Th. Udem // Science. - 2008. -Vol. 321, Issue 5894. - P. 1335-1337. doi: 10.1126/science.1161030

6. Li, C.-H. A laser frequency comb that enables radial velocity measurements with a precision of 1 cm s(-1) [Text] / C.-H. Li, A. J. Benedick, P. Fendel, A. G. Glenday, F. X. Kartner, D. F. Phillips, D. Sasselov, A. Szentgyorgyi,

R. L. Walsworth // Nature. - 2008. - Vol. 452, Issue 7187. -P. 610-612. doi: 10.1038/nature06854

7. Li, H. Near-infrared diode laser absorption spectroscopy with applications to reactive system and combustion control [Text]: a dissertation / H. Li. - Submitted to the department of mechanical engineering and the committee on graduate studies of Stanford university, 2007. - 166 p.

8. Li, S. Optical fiber remote sensing system of methane at 1645nm using wavelength-modulation technique [Text] /

S. Li, T. Koscica, Y. Zhang, D. Li, H.-L. Cui. - Department of Physics and Engineering Physics , Stevens Institute of Technology, 2008

9. Shimose, Y. Remote sensing of methane gas by differential absorption measurement using a wavelength tunable DFB LD [Text] / Y. Shimose, T. Okamoto, A. Maruyama, M. Aizawa, H. Nagai // IEEE Photonics Technology Letters. -1991. - Vol. 3, Issue 1. - P. 86-87. doi: 10.1109/68.68057

10. Gamache, R. R. Total internal partition sums for molecules in the terrestrial atmosphere [Text] / R. R. Gamache, S. Kennedy, R. Hawkins, L. S. Rothman // Journal of Molecular Structure. - 2000. - Vol. 517-518. - P. 407-425. doi: 10.1016/s0022-2860(99)00266-5

11. Nagali, V. Design of a diode-laser sensor to monitor water vapour in high-pressure combustion gases [Text] / V. Nagali, R. K. Hanson // Applied Optics - 1997. - Vol. 36, Issue 36. - P. 9518-9527. doi: 10.1364/ao.36.009518

12. Chan, K. An Optical-Fiber-Based Gas Sensor for Remote Absorption Measurement of Low-Level CH4 Gas in the Near-Infrared Region [Text] / K. Chan, H. Ito, H. Inaba // Journal of Lightwave Technology - 1984. - Vol. 2, Issue 3. -P. 234-237. doi: 10.1109/jlt.1984.1073609

References

1. Carbon Dioxide, Methane Rise Sharply in 2007. Available at: Noaanews.noaa.gov (Last accessed: 2008-04-23).

2. Byrnes, J. (2009). Unexploded Ordnance Detection and Mitigation. Springer, 21-22

3. Takamoto, M., Hong, F. L., Higashi, R., Katori, H. (2005). An optical lattice clock. Nature, 435 (7040), 321-324.

4. Lee, J., Kim, Y.-J., Lee, K., Lee, S., Kim, S.-W.

(2010). Time-of-flight measurement with femtosecond light pulses. Nature Photonics, 4 (10), 716-720.

doi: 10.1038/nphoton.2010.175

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5. Steinmetz, T., Wilken, T., Araujo-Hauck, C.,

Holzwarth, R., Hansch, T. W., Pasquini, L., Manescau, A., D’Odorico, S., Murphy, M. T., Kentischer, T., Schmidt, W., Udem, Th. (2008). Laser frequency combs for astronomical observations. Science, 321 (5894), 1335-1337.

doi: 10.1126/science.1161030

6. Li, C.-H., Benedick, A. J., Fendel, P., Glenday, A. G., Kartner, F. X., Phillips, D. F., Sasselov, D., Szentgyorgyi, A., Walsworth, R. L. (2008). A laser frequency comb that enables radial velocity measurements with a precision of 1 cm s(-1). Nature, 452 (7187), 610-612. doi: 10.1038/nature06854

7. Li, H. (2007). Near-infrared diode laser absorption spectroscopy with applications to reactive system and combustion control. Submitted to the department of mechanical engineering and the committee on graduate studies of Stanford university, 166.

8. Li, S., Koscica, T., Zhang, Y., Li, D., Cui, H.-L. (2008). Optical fiber remote sensing system of methane at 1645nm using wavelength-modulation technique. Department of Physics and Engineering Physics , Stevens Institute of Technology.

9. Shimose, Y., Okamoto, T., Maruyama, A., Aizawa, M., Nagai, H. (1991). Remote sensing of methane gas by differential absorption measurement using a wavelength tunable DFB LD. IEEE Photonics Technology Letters, 3 (1), 86-87. doi: 10.1109/68.68057

10. Gamache, R. R., Kennedy, S., Hawkins, R.,

Rothman, L. S. (2000). Total internal partition sums for molecules in the terrestrial atmosphere. Journal of Molecular Structure, 517-518, 407-425. doi: 10.1016/s0022-

2860(99)00266-5

11. Nagali, V., Hanson, R. K. (1997). Design of a diode-laser sensor to monitor water vapour in high-pressure combustion gases. Applied Optics, 36 (36), 9518-9527. doi: 10.1364/ao.36.009518

12. Chan, K., Ito, H., Inaba, H. (1984). An Optical-

Fiber-Based Gas Sensor for Remote Absorption Measurement of Low-Level CH4 Gas in the Near-Infrared Region. Journal of Lightwave Technology, 2 (3), 234-237.

doi: 10.1109/jlt.1984.1073609

Рекомендовано до публікації д-р техн. наук Мичехін Ю. П.

Дата надходження рукопису 31.10.2014

Haider Ali Muse, Faculty of electronic engineering, Department of Physical Foundations of Electronic Engineering, Kharkiv national university of radio electronics, st. Lenina 14, Kharkov, 61000 Hadr 2005@yahoo.com

UDC 629.735.02:681.518.5

DOI: 10.15587/2313-8416.2014.29267

AERODYNAMIC STATE DIAGNOSING METHOD OF AIRCRAFT WITH THERMAL FIELD USAGE

© V. Kazak, D. Shevchuk, A. Babenko, M. Levchenko

The method of aerodynamic condition of the aircraft on the thermal fields was developed as a research result. Based on the mathematical and natural experiments, there are identified the regularities of formation of temperature gradients in the boundary layer of air that occurs after damage of external contours; there are detected parameters that affect the behavior of the temperature gradient arising from damage.

Keywords: external contour, damage, plane, aircraft, temperature gradient, thermal method, boundary layer, diagnostics.

В результаті проведених досліджень було розроблено метод аеродинамічного стану літака по теплових полях. На основі математичного та натурного експериментів, встановлено: закономірності формування температурного градієнту у прикордонному шарі повітря, що виникає за пошкодженням зовнішніх обводів; виявлено параметри, які впливають на поведінку температурного градієнту, що виникає за пошкодженням.

Ключові слова: зовнішні обводи, пошкодження, повітряний корабель, температурний градієнт, тепловий метод, прикордонний шар, діагностування.

1. Introduction

The issue of safety, including reducing the number of aviation accidents with fatalities worldwide, regardless of the amount of air transportation is a primary objective of the international Civil Aviation Organization (ICAO: Global Aviation Safety Plan, 2011, Montreal, Canada). According to the Federal Aviation Administration USA (FAA) annually in civil aviation there are about five huge aircraft accidents in which an important role is played by the collision of aircraft with biological, mechanical or electrical forces. At the same time every year a growing number of aircraft collisions with external forces, due to

several factors, namely the increasing intensity of operations and the increase in bird populations. In particular, the number of aircraft collisions with birds in flight over the period 2005-2013 biennium. Has almost doubled - from 36,000 to 70,000 cases of collision per year for all types of civil aviation [1-3].

Thus the danger of accidental injuries in the collision of aircraft with the above units is that the appearance of lesions can not be predicted or detected in a timely flight. Analysis of Accident Investigation showed that the highest probability of collision with mechanical, electrical and biological formations appears

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