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324 ◾ Index Atmospheric turbulence (Continued) Bifurcation energy cascade theory, 13–16 at breakdown of main vortex, 136 functions and parameters of, 16–19 of stability alternation, 125 Hill’s model, 22 Big alt-azimuthal telescope (BAT), 76–77, 161; Kolmogorov spectrum, 19, 20 see also Coherent structures modified vs. von Kármán normalized air motion in dome space, 161, 163 spectra, 23 dome with side heated by sun, 162 non-Kolmogorov turbulence, 23 temporal frequency spectra of temperature optical turbulence, 17 fluctuations, 163 passive scalar, 20 turbulence formation, 164 refractive index, 17, 18 Boussinesq approximation, 161 spectral characteristics of, 19–23 BPA, see Backpropagation algorithm spectrum, 13 Brewster angle, 36 Tatarskii spectrum, 22 Broadband laser radiation sources, 266 2/3 power law, 16 von Kármán spectrum, 21 C Wiener–Khinchin theorem, 19, 20 Cauchy problem, 38, 206 B Cell, 141 Chaos in typical dynamic systems, 74, Backpropagation algorithm (BPA), 279, 156, 166 280–281 Chaotization period, 77 Backscattering coefficients, 271 Characteristic of measurement path, 93–95 Backscattering efficiency factor, 271 Characteristics of radiation, effective, 220 Ballistic photons, 250 Chessboard-like structure, 128, 141 BAT, see Big alt-azimuthal telescope Closed local volumes, 73, 120 Beam Cloud cover models, 12; see also Hydrometeors centroid, 199 Clouds, 11–12; see also Hydrometeors of different profile, 199, 211 Cluster expansion of centered random function Gaussian, 213 and Fourier transform, 41–42 ring, 224 Coherent structures, 74; see also Anisotropic super-Gaussian, 213 boundary layer; Mountain boundary Beam divergence vs. nonlinearity length, 203 layer; Semiempirical theory of Beam parameters, effective, 220 turbulence; Turbulence Beam radius, effective, 225–229 attenuation effect of refractive Beam self-action, 195; see also Nonlinear fluctuations, 153 propagation of laser radiation attenuation of amplitude and phase beam divergence vs. nonlinearity fluctuations, 150–154 length, 203 bifurcation of stability alternation, 125 feature of, 196 cell, 141 influence of atmosphere on, 196 coherent turbulence, 143–146 longitudinal scale of nonlinearity, 201 extension of coherent structure concept, method of characteristics, 197–198 139–143 radiation brightness transfer Gerris Flow Solver, 160 equation, 197 incipient convective turbulence, 123–125 ray approximation, 197 incipient turbulence, 121, 124 relative effective beam intensity, 201 incoherent turbulence, 143–146 relative effective beam radius vs. jitter of astronomical images, 152, 153 dimensionless distance, 199 Kolmogorov turbulence, 143, 144 effect of thermal blooming, 195–196 lifetime of, 75 Benard cell, 129 lifetimes of turbulence, 154 formation and breakdown, 72 main results, 166–167 168 ◾ Optical Waves and Laser Beams in the Irregular Atmosphere 2. Monin, A. S., and Yaglom, A. M., Statistical Fluid Mechanics: Mechanics of Turbulence, vol. 2. Cambridge, MA: MIT Press, 1975. 3. Monin, A. S., and Obukhov, A. M., Main regularities of turbulent mixing in the near-surface atmospheric layer, Trudy Geofiz. Inst. AN SSSR., vol. 24, No. 151, pp. 163–187, 1954; Dokl. Akad. Nauk SSSR, vol. 93, No. 2, pp. 223–226, 1953. 4. Tatarskii, V. I., Wave Propagation in the Turbulent Atmosphere. Moscow: Science, 1967, 548 p. 5. Landau, L. D., and Livshits, E. M., Fluid Dynamics. Moscow: Science, 1988, 736 p. 6. Monin, A. S., Hydrodynamics of the Atmosphere, Ocean, and Earth Interior. St. Petersburg: Gidrometeoizdat, 1999, 524 p. 7. Zilitinkevich, S. S., Dynamics of the Atmospheric Boundary Layer. Leningrad: Gidrometeoizdat, 1970, 290 p. 8. Gurvich, A. S., Vertical profiles of wind velocity and temperature in the near-surface atmospheric layer, Izv. AN SSSR. Phys. Atmos. Okeana, vol. 1, No. 1, pp. 55–64, 1965. 9. Nosov, V. V., Emaleev, O. N., Lukin, V. P., and Nosov, E. V., Semi-empirical hypoth- eses of turbulence theory in the anisotropic boundary layer, Atmospheric and Oceanic Optics, vol. 18, No. 10, pp. 756–773, 2005. 10. Kozhevnikov, V. N., Perturbation of the Atmosphere at Flowing around Mountains. Moscow: Nauchn. Mir, 1999, 160 p. 11. Nosov, V. V., Emaleev, O. N., Lukin, V. P., and Nosov, E. V., Semiempirical hypoth- eses of the turbulence theory in anisotropic boundary layer, Proc. SPIE, vol. 5743, pp. 110–131, 2004. 12. Nosov, V. V., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Discrete-uninterrupted averaging in Taylor ergodic theorem, Proc. SPIE, vol. 6160, pp. 358–362, 2005. 13. Nosov, V. V., Grigorev, V. M., Kovadlo, P. G., Lukin, V. P., and Torgaev, A. V., Results of measurement of astroclimatic characteristics near Large Solar Vacuum Telescope, Solar-Terrestrial Physics, Issue 9, pp. 104–109, 2006. 14. Nosov, V. V., Grigorev, V. M., Kovadlo, P. G., Lukin, V. P., Papushev, P. G., Torgaev, A. V., Results of measurement of astroclimatic characteristics in the dome space of AZT-33 telescope of Sayan Sun Observatory of the Institute of Solar-Terrestrial Physics SB RAS, Solar-Terrestrial Physics, Issue 9, pp. 101–103, 2006. 15. Nosov, V. V., Lukin, V. P., Emaleev, O. N., and Nosov, E. V., Semiempirical hypoth- esis of turbulence theory in the atmospheric anisotropic boundary layer (for moun- tain region), in Instrumentation, Measure, Metrologie (RS-I2M), 1631–4670, vol. 6, No. 1–4, Paris, France: Lavoisier Pub., 2006, pp. 155–160. 16. Nosov, V. V., Grigorev, V. M., Kovadlo, P. G., Lukin, V. P., and Torgaev, A. V., Mea- surements of local astroclimate characteristics near the large solar vacuum telescope, Proc. SPIE, vol. 6522, pp. 65220T-1– 65220T-8, 2006. doi: 10.1117/12.723063. 17. Nosov, V. V., Lukin, V. P., Emaleev, O. N., and Nosov, E. V., Semiempirical hypoth- eses of the turbulence theory in the atmospheric anisotropic boundary layer, in Vision for Infrared Astronomy, Lavoisier service editorial, Paris, France: Hermes, 2006, pp. 219–223. 18. Lukin, V. P., Lavrinov, V. V., Botygina, N. N., Emaleev, O. N., and Nosov, V. V., Turbulence and wind velocity measurements under differential image motion meter, Proc. SPIE, vol. 6830, pp. 56–59, 2007. 19. Lukin, V. P., Lavrinov, V. V., Botygina, N. N., Emaleev, O. N., and Nosov, V. V., Differential turbulence and wind velocity meters, Proc. SPIE, vol. 6733, p. 6733ON, 2007. 174 ◾ Optical Waves and Laser Beams in the Irregular Atmosphere 103. Nosov, V. V., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Measurements of A.M. Obukhov constant in Kolmogorov–Obukhov law, in XV Joint Int. Symp. Atm. and Ocean Optics. Atm. Phys., Tomsk, 2008, pp. 73–74. 104. Nosov, V. V., Lukin, V. P., and Torgaev, A. V., A temperature fluctuations structural function in coherent turbulence, in XV Joint Internat. Symp. Atm. and Ocean Optics. Atm. Phys., Tomsk, 2008, pp. 67–68. 105. Nosov, V. V., Lukin, V. P., and Torgaev, A. V., Decrease of the light wave fluctuations in coherent turbulence, in XV Joint Int. Symp. Atm. and Ocean Optics. Atm. Phys., Tomsk, 2008, pp. 68–69. 106. Nosov, V. V., Grigorev, V. M., Kovadlo, P. G., Lukin, V. P., and Torgaev, A. V., Astroclimatic measurements in HST—telescope, in XV Joint Int. Symp. Atm. and Ocean Optics. Atm. Phys., Tomsk, 2008, pp. 81. 107. Nosov, V. V., Grigor’ev, V. M., Kovadlo, P. G., Lukin, V. P., and Torgaev, A. V., Measurements of the astroclimate characteristics nearby LSVT entrance mirror, in XV Joint Int. Symp. Atm. and Ocean Optics. Atm. Phys., Tomsk, 2008, pp. 82. 108. Nosov, V. V., Grigor’ev, V. M., Kovadlo, P. G., Lukin, V. P., Papushev, P. G., and Torgaev, A. V., Repeated testing of the under dome astroclimate of telescope AZT-33, in XV Joint Int. Symp. Atm. and Ocean Optics. Atm. Phys., Tomsk, 2008, pp. 80–81. 109. Nosov, V. V., Grigorev, V. M., Kovadlo, P. G., Lukin, V. P., Papushev, P. G., and Torgaev, A. V., Repeated testing of under dome astroclimate of AZT-33 telescope, Proc. SPIE, vol. 7296, [7296-08], pp. 729608-1–5, 2008. 110. Nosov, V. V., Grigorev, V. M., Kovadlo, P. G., Lukin, V. P., and Torgaev, A. V., A surface layer astroclimatic characteristics in the Sayan solar observatory, in XV Joint Intern. Symp. “Atm. and Ocean Optics. Atm. Phys.”, Tomsk, 2008, BP-05, pp. 82–83. 111. Nosov, V. V., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Some generalizations of the Taylor ergodic theorem, in XII Joint Int. Symp. Atm. and Ocean Optics. Atm. Phys., Tomsk, 2005, D-45, pp. 202. 112. Nosov, V. V., Grigorev, V. M., Kovadlo, P. G., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Coherent structures are elementary components of the atmospheric turbulence, Izv. Vuz., Phys., vol. 55, pp. 236–238, 2012. 113. Nosov, V. V., Lukin, V. P., Nosov, E. V., Torgaev, A. V., Grigorev, V. M., and Kovadlo, P. G., The Solitonic Hydrodynamical Turbulence, in Proc. VI Int. Conf. “Solitons, Collapses and Turbulence: Achievements Developments and Perspectives”, Novosibirsk, 2012, pp. 108–109. 114. Nosov, V. V., Grigor’ev, V. M., Kovadlo, P. G., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., The problem of coherent turbulence, Vestnik MSTU “Stankin”, vol. 24, No. 1, pp. 103–107, 2013. 115. Nosov, V. V., Grigor’ev, V. M., Kovadlo, P. G., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Coherent components of the turbulence, in The Int. Conf. dedicated to the mem- ory of academician “Turbulence, Atmosphere and Climate Dynamics”, Obukhov, A. M. Ed. Moscow: GEOS, IPA RAS, 2013, pp. 43–47. 116. Banakh, V. A., Belov, V. V., Zemlyanov, A. A., Krekov, G. M., Lukin V. P., Matvienko, G. G., Nosov, V. V., Sukhanov, A. Ya., and Falits, A. V., Optical Waves Propagation in the Inhomogeneous, in Random, Non-Linear Media, Zemlyanov, A. A. Ed. Tomsk: Publishing House of the V.E. Zuev Institute of Atmospheric Optics SB RAS, 2012, p. 404. 117. Nosov, V. V., Lukin, V. P., Torgaev, A. V., and Kovadlo, P. G., Atmospheric coherent turbulence, Atmospheric and Oceanic Optics, vol. 26, pp. 201–206, 2013. 176 ◾ Optical Waves and Laser Beams in the Irregular Atmosphere Volume Turbulence (pcDVT), OSA, USA, Seattle, Washington, 2014, Paper PM4E.2, ISBN: 978-1-55752-308-2, Control Number: 2041404. 134. Lukin, V. P., Nosov, V. V., Kovadlo, P. G., Nosov, E. V., and Torgaev, A. V., Intermittency of jitter of the astronomical images is non-Kolmogorov turbulence effect, in Imaging and Applied Optics Congress. Propagation through and Characterization of Distributed Volume Turbulence (pcDVT), OSA, USA, Seattle, Washington, 2014, Paper PM4E.3, ISBN: 978-1-55752-308-2, Control Number: 2041428. 135. Nosov, V. V., and Lukin, V. P., Measurement technique of turbulence characteris- tics from jitter of astronomical images onboard an aircraft: Part 1. Main ergodic theorems, Atmospheric and Oceanic Optics, vol. 27, No. 1, pp. 75–87, 2014. 136. Nosov, V. V., and Lukin, V. P., Measurement technique of turbulence characteristics from jitter of astronomical images onboard an aircraft: Part 2. Accounting for photore- ceiver response time, Atmospheric and Oceanic Optics, vol. 27, No. 1, pp. 88–99, 2014. 137. Nosov, V. V., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Approximations of the synoptic spectra of atmospheric turbulence by sums of spectra of coherent structures, Proc. SPIE, vol. 9910, pp. 99101Y1–6, 2016. 138. Lukin, V. P., Nosov, V. V., Nosov, E. V., and Torgaev, A. V., Approximations of the synoptic spectra of atmospheric turbulence by sums of spectra of coherent structures, in Conference “SPIE Astronomical Telescopes + Instrumentation”, Edinburgh, United Kingdom, Paper 9910-75, 2016. 139. Nosov, V. V., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Causes of non-Kol- mogorov turbulence in the atmosphere, Applied Optics, vol. 55, pp. B163–168, 2016. 140. Nosov, V. V., Lukin V. P., Kovadlo P. G., Nosov E. V., and Torgaev A. V., Optical Properties of the Turbulence in the Atmospheric Mountain Boundary Layer. Novosibirsk: Publishing House of the Siberian Branch of the Russian Academy of Sciences, 2016, p. 153. 141. Nosov, V. V., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Intermittency of the astronomical images jitter in the high-mountain observations, Proc. SPIE, 20th International Symposium on Atmospheric and Ocean Optics: Atmospheric Physics (AOO14), Novosibirsk, vol. 9292, pp. 92920V-1-4, 2014. 142. Nosov, V. V., Grigor’ev, V. M., Kovadlo, P. G., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., The effect of turbulence intermittency in the mountainous observa- tions, Izv. Vuz., Phys., vol. 58, No. 8/3, pp. 210–213, 2015. 143. Nosov, V. V., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Approximations of the synoptic spectra of atmospheric turbulence by sums of spectra of coherent structures, Proc. SPIE, vol. 9680, pp. 9680 OQ, 2015. 144. Nosov, V. V., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Simulation of coherent structures (topological solitons) inside closed rooms by solving numerically hydrody- namic equations, Atmospheric and Oceanic Optics, vol. 28, pp. 120–133, 2015. 145. Nosov, V. V., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Simulation of coherent structures (topological solitons) indoors by numerical solving of hydrodynamics equations, Proc. SPIE, vol. 9292, pp. 92920U-1–14, 2014. 146. Nosov, V. V., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Structure of air motion along optical paths inside specialized rooms of astronomical telescopes. Numerical simulation, Atmospheric and Oceanic Optics, vol. 28, No. 7, pp. 614–621, 2015. 147. Nosov, V. V., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Structure of turbu- lence at specialized optical paths in astronomical telescopes, Izv. Vuz., Phys., Issue 11, pp. 905–910, 2016. 178 ◾ Optical Waves and Laser Beams in the Irregular Atmosphere 167. Feigenbaum, M. J., Quantitative universality for a class of nonlinear transformations, J. Stat. Phys., vol. 19, No. 1, pp. 25–32, 1978. 168. Ruelle, D., and Takens, F., On the nature of turbulence, Comm. Math. Phys., vol. 20, No. 2, pp. 167–192, 1971; Ruelle, D., Strange attractors, Math. Intellengencer, vol. 2, No. 3, pp. 126–137, 1980. 169. Zaslavskii, G. M., and Sagdeev, R. Z., Introduction to Nonlinear Physics: From Pendulum to Turbulence and Chaos. Moscow: Science, 1988, p. 368. 170. Zaslavskii, G. M., Stochasticity of Dynamic Systems. Moscow: Science, 1984, p. 272. 171. Schuster, H. G., Deterministic Chaos: An Introdcution. Weinheim: Physik-Verlag, 1984, p. 240. 172. Van Atta, C. W., Effect of coherent structures on structure functions of temperature in the atmospheric boundary layer, Arch. Mech., vol. 29, No. 1, pp. 161–171, 1977. 173. Danaila, I., Dusek, J., and Anselmet, F., Coherent structures in a round, spatially evolving, unforced, homogeneous jet at low Reynolds numbers, Phys. Fluids, vol. 9, No. 11, pp. 3323–3342, 1997. 174. Darchiya, Sh. P., Ivanov, V. I., and Kovadlo, P. G., Results of astroclimatic studies in SibIZMIR SB AS USSR in 1971-1976, Nov. Tekhn. Astronom., Leningrad: Science, Issue 6, pp. 168–176, 1979. 175. Mironov V. L., and Nosov V. V., On influence of the outer scale of atmospheric turbulence on the spatial correlation of random displacements of optical beams, Izv. Vuz., Radiophys., vol. 17, No. 2, pp. 274–281, 1974. 176. Kon, A. I., Mironov, V. L., and Nosov, V. V., Fluctuations centroids of optical beams in the turbulent atmosphere, Izv. Vuz., Radiophys., vol. 17, No. 10, pp. 1501–1511, 1974. 177. Mironov, V. L., Nosov, V. V., and Chen, B. N., Jitter of optical images of laser sources in the turbulent atmosphere, Izv. Vuz., Radiophys., vol. 23, No. 4, pp. 461–470, 1980. 178. Gurvich, A. S., Kon, A. I., Mironov, V. L., and Khmelevtsov, S. S., Laser Radiation in the Turbulent Atmosphere. Moscow: Science, 1976, p. 277. 179. Nosov, V. V., Lukin, V. P., and Nosov, E. V., Influence of the underlying terrain on the jitter of astronomic images, Atmospheric and Oceanic Optics, vol. 17, No. 4, pp. 321–328, 2004. 180. Nosov, V. V., Lukin, V. P., and Nosov, E. V., Effect of underlying terrain on jitter of astronomic images, Proc. SPIE, vol. 5396, pp. 132–141, 2003. 181. Kline, J., Reynolds, W. C., Schraub, F. A., and Runstadler, P. W., The structure of turbulent boundary layers, J. Fluid Mech., vol. 30, pp. 741–773, 1967. 182. Temam, R., Navier–Stokes Equations and Nonlinear Functional Analysis. Philadelphia, PA: The Society for Industrial and Applied Mathematics, 1995, p. 142. 183. Drobinski, P., Carlotti, P., Redelsberger, J.-L., Banta, R. M., Masson, V., and Newsom, R. K., Numerical and experimental investigation of the neutral atmospheric surface layer, J. Atmos. Sci, vol. 64, pp. 137–156, 2007. 184. Foster, R.C., Vianey, F., Drobinski, P., and Carlotti, P., Near-surface coherent structures and the vertical momentum flux in a large-eddy simulation of the neu- trally-stratified boundary layer, Boundary-Layer Meteorology, vol. 120, pp. 229–255, 2006. 185. Popinet, S., The Gerris Flow Solver. A free, open source, general-purpose fluid mechanics code (2001-2013), 2013, http://gfs.sf.net 186. Popinet, S., Gerris: A tree-based adaptive solver for the incompressible Euler equations in complex geometries, J. Comput. Phys., vol. 190, pp. 572–600, 2003. 126 ◾ Optical Waves and Laser Beams in the Irregular Atmosphere As was shown in Reference 4, the temporal frequency spectra of temperature fluctuations W (f ) in open air are satisfactorily described by the von Kármán T model. Spectra of Kolmogorov developed turbulence have the extended inertial range, in which W ∼ f−5/3 (see also Chapter 1). In this range, the energy is trans- T ferred from vortices with scales to smaller ones. Figure 3.24 depicts the smoothed temporal frequency spectra of temperature fluctuations W in a closed room and in open air. T As follows from Figure 3.24, in comparison with the open air, the spectra in the closed room decrease much faster in the inertial range. In addition, in this range, there are only some short frequency sections (located stepwise), in which the tur- bulence can be considered as Kolmogorov (W ∼ f−5/3). These sections are observed T between steps of the spectral function at frequencies corresponding to local maxima of the correlation function of fluctuations (or minima of the structure function). If we smooth the steps, then the experimental spectra of undeveloped turbulence have some characteristic parts with the fast power-law decrease. Thus, if W ∼ const in T the extended energy range, then with the increase of the frequency (in the inertial range) first W ∼ f−8/3, and then W ∼ f−12/3. Consequently, in incipient turbu- T T lence, the energy transfer from large vortices to smaller ones is insignificant, that is, vortices are slightly blurred. With the further increase of the frequency, in the vis- cous range, where the spectral density is close to the noise level, the decrease of the spectrum becomes more slowly, W ∼ f−2/3. The analogous behavior of the spectra T is also observed at other measurement points in the pavilion. At some points, the stepwise form of the spectrum is even more pronounced. To construct the theoretical model Φ (æ) of the temperature spectrum of T incipient turbulence, we can use the von Kármán model with the decrease in the 101 3 2 1 10–1 z) H 2/ g (deT10–3 12 –– OClpoesned a irroom W 3 – ∼ f –5/3 4 – W (f), ν = 5/6 10–5 T 1 5 – W (f), ν = 1/3 5 T 2 4 0.01 0.1 1 10 100 f (Hz) Figure 3.24 Smoothed temporal frequency spectra of temperature fluctuations W in a closed room and in open air. T 130 ◾ Optical Waves and Laser Beams in the Irregular Atmosphere 1.0 101 0.8 2/Hz) 100 1 2345678910 9 g 0.6 10 7 ) (de10–1 0.4 6 5 W(f10–2 τb() 4 10–3 0.2 8 0.01 0.1 1 3 f (Hz) 0.0 2 1 –0.2 –0.4 0 20 40 60 80 100 120 τ (s) Figure 3.26 Correlation coefficient b and nonsmoothed frequency spectrum T W (top right inset) in the pavilion. Digits are numbers of maxima of b and W T T T corresponding to each other. The selected spectrum W is calculated without smoothing with a rect- T angular spectral window. As known [164,165], this window acts as a slit with the width ∼2/T (T = 120 s). This resolution is quite sufficient to find maxima of the spectrum W being in one-to-one correspondence with the T maxima of b. The arguments of b and W maxima are connected by the T T T relation τ f = 1, k = 1, 2,… (the values of τ, f usually determine char- k k 1 1 acteristic scales of decrease of the functions b and W ). From the relation T T 2πR = υ τ = υ/f , we can easily reconstruct the diameter 2R of the main 1 1 1 1 energy-carrying vortex. In the pavilion, it is equal to 294.4 cm (υ = 9 cm/s, f = 0.00973 Hz) at point 5. 1 From comparison of spectra W shown in Figures 3.24 and 3.26, we can T see that at the standard smoothing of the spectrum by a wide spectral win- dow (variance of the smoothed spectrum in Figure 3.24 is 1% of the vari- ance of the selected spectrum in Figure 3.26) actual maxima of the spectra disappear. Therefore, to calculate the frequencies of spectral maxima (har- monics), we should use data of Figure 3.26. However, a rectangular spec- tral window has large side lobes leading to oscillations, especially at high frequencies. We can dispose of these lobes by applying any of widely used nonrectangular windows (the difference between them is small), for exam- ple, the Welch window [166]. In comparison with the rectangular window, this window decreases the variance approximately two times, increasing the width of the frequency band also approximately two times. The increase of the band is acceptable, because it turns out to be smaller than the average width of the spectral maxima, which can be seen from the data for W in T Figure 3.26. 132 ◾ Optical Waves and Laser Beams in the Irregular Atmosphere In this case, the oscillations themselves are usually called coherent (inphase). It should be noted that the function f /(nf ) shown in Figure 3.27 is resistant n 1 to variations of the level of the threshold filter. Variations of this function appear to be i nsignificant at variations of the filter level. From the frequen- cies f , using the relation 2πR = υ/f , n = 1, 2,…, following from the law n n n of c onservation of momentum of a liquid particle at remote edges of the breaking down vortex and its daughter vortices (Heisenberg equality [1,2]), we can calculate the corresponding vortex radii R (in cm): n R =147.21,24.52,18.39,13.38,11.32,8.66,7.36,2.23,2.16,1.91,,1.63,1.58, n 1.35,1.30,1.26,1.23,1.16,1.13,1.11,1.08,1.02,0..98,0.97,0.94,0.91,0.90, 0.88,0.84,0.82,0.80,… The vortex diameters are shown in Figure 3.28. From the comparison of the data in Figure 3.28 and Table 3.1 (point 5, ν = 5/6), we can see that the second frequency 6f corresponds approximately 1 to the outer scale LK (2R = 294 cm, 2R = 49 cm), while the frequencies 0 1 2 127f and 130f (at which the inertial range terminates) correspond to the 1 1 inner scale l (2R = 2.3 cm). 0 17 In the viscous range and in a part of the inertial range, vortices being products of breakdown of large vortices (their frequencies are multiple to the lower frequencies) are observed. For example, f /f =11,15,20,24,25,…(n=8,11,16,21,22,…); n 2 f /f =15,17,18,199,36,…(n=16,2 0, 21, 23 , 52 ,…). n 3 800 R = R /β n n/2 m) 100 fn L0 (cn Rn ~ n–2.22, β = δ R x 2 10 Rn ~ n–1, β = 2 e rt o v of 1 l r 0 e met ~n–1 Dia 0.1 ~n–2.22 0.01 1 10 100 1000 3000 n (number of harmonic) Figure 3.28 Diameters of stable harmonics (vortices) 2R in the W fluctuation n T spectrum. 148 ◾ Optical Waves and Laser Beams in the Irregular Atmosphere –0.00 D uuu –0.02 100 –0.04 Hz) ~ f –8/3 2g/10–2 e d (T10–4 –0.06 W DuTT 10–6 0.1 1 10 100 f (Hz) –0.08 0 1 2 τ (s) Figure 3.32 Third moments of the longitudinal difference of velocity and tem- perature D (m3/s3), D (deg2m/s). Smoothed spectrum (bottom left inset). uuu uTT Coherent turbulence, summer daytime measurements in mountains at a height of 680 m, July 2, 2007. 9 Cθ Cθ = 5.99 6 C = 2.93 3 3 C 1.9 0 1.0 1.5 2.0 2.5 τ (s) Figure 3.33 Kolmogorov C and Obukhov C constants. Coherent turbulence θ measured in mountains at a height of 680 m, July 2 of 2007. Vertical lines show the boundaries of the inertial range, and dashed lines are the average values of the constants C and C . θ law) are accompanied by significant errors, as a rule. The data of our measure- ments indicate the main cause for appearance of these errors. Variations of the Kolmogorov and Obukhov constants within 100% (depending on the observation point) lead to practically the same errors in determination of the characteristics C2, C2, and C2. T V n 170 ◾ Optical Waves and Laser Beams in the Irregular Atmosphere near-surface values, in VI Int. Symposium Atmospheric and Ocean Optics, IAO SB RAS, Tomsk, 1999, pp. 55. 36. Nosov, V. V., Lukin, V. P., Torgaev, A. V., Grigor’ev, V. M., and Kovadlo, P. G., Astroclimate parameters of the surface layer in the Sayan solar observatory, Proc. SPIE, vol. 7296, pp. 72960D-1–8, 2009. 37. Nosov, V. V., Lukin, V. P., Torgaev, A. V., Grigor’ev, V. M., and Kovadlo, P. G., Result of measurements of the astroclimate characteristics of astronomical telescopes in the mountain observatories, Proc. SPIE, vol. 7296, pp. 72960C-1–5, 2009. 38. Lukin, V. P., Grigor’ev, V. M., Antoshkin, L. V., Botygina, N. N., Emaleev, O. N., Konyaev, P. A., Kovadlo, P. G., Nosov, V. V., Skomorovskii, V. I., and Torgaev, A. V., Possibilities of using adaptive optics in solar telescopes, Optika Atmosfery i Okeana, vol. 22, No. 5, pp. 499–511, 2009. 39. Nosov, V. V., Grigor’ev, V. M., Kovadlo, P. G., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Turbulent scales of velocity and temperature in the atmospheric boundary layer, Izv. Vuz., Phys., vol. 56, No. 8\3, pp. 331–333, 2013. 40. Nosov, V. V., Grigor’ev, V. M., Kovadlo, P. G., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Turbulent scales of the Monin–Obukhov similarity theory in aniso- tropic boundary layer, in Proc. Int. Conf. in Memory of Academician A.M. Obukhov “Turbulence, Atmospheric Dynamics, and Climate,” I. Turbulence, Moscow, IPhA RAS, 2013, pp. 38–43. 41. Nosov, V. V., Grigorev, V. M., Kovadlo, P. G., Lukin, V. P., Nosov, E. V., and Torgaev, A. V., Turbulent Prandtl number, in Proc. XVII Int. Symp. “Atmospheric and Ocean Optics. Atmospheric Physics”, IAO SB RAS, Tomsk, D-66, 2011, pp. D235–D238. 42. Zhigulev, V. N., and Tumin, A. M., Formation of Turbulence. Novosibirsk: Science, 1987, 283 p. 43. Townsend, A. A., Measurements in the turbulent wake of a cylinder, Proc. Roy. Soc., London, Ser.A, vol. 190, pp. 551–561, 1947. 44. Townsend, A. A., The Structure of Turbulent Shear Flow, 1st ed. Cambridge: Cambridge University Press, 1956, 429 pp. 45. McNaughton, K. G., and Brunet, Y., Townsend’s hypothesis, coherent structures and Monin–Obukhov similarity, Boundary-Layer Meteorology, vol. 102, No. 2, pp. 161–175, 2002. 46. McNaughton, K. G., Turbulence structure of the unstable atmospheric surface layer and transition to the outer layer, Boundary-Layer Meteorology, vol. 112, No. 2, pp. 199–221, 2004. 47. Kit, E., Krivonosova, O., Zhilenko, D., and Friedman, D., Reconstruction of large coherent structures from SPIV measurements in a forced turbulent mixing layer, Experiments in Fluids, vol. 39, No. 4, pp. 761–770, 2005. 48. Solomon, T. H., and Gollub, J. P., Chaotic particle transport in time-dependent Rayleigh–Benard convection, Physical Review A, vol. 38, No. 12, pp. 6280–6286, 1988. 49. Solomon, T. H., and Gollub, J. P., Thermal boundary layers and heat flux in turbu- lent convection: The role of recirculating flows, Physical Review A, vol. 43, No. 12, pp. 6683–6693, 1991. 50. Blackwelder, R. F., and Kovasznay, L. S. G., Time scale and correlation in a turbulent boundary layer, Phys. Fluids, vol. 15, pp. 1545–1554, 1972. 51. Blackwelder, R. 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