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The paper considers the infrared characteristic radiation (IRCR) during the first order phase transitions (crystallization, condensation and sublimation) of water. The experimental results show that when the particles (atoms, molecules, clusters) transfer from a higher energetic level to a lower level, partly of the latent heat will be liberation a...
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... to the references( Mestvirishvili and Perelman,1977),the experiment performed by Mestvirishvili and Perelman for the semiqualitative estimate of the water phase transition is presented in this paper.This experimental set-up for the investigation of the vapor-water transition is shown in fig.3.The results of experiment was detected by the infrared bolometer which included in the Wheatstone bridge(through testing the numerical value of the current or voltage to compare with photon energy at the different spectrum) out a microvoltmeter.When plunger is lifted up, the vessel is full of the saturated vapor. The reverse plunger motion leads to a 0.1g vapor condensation on the average. ...
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This paper presents new experimental evidence of the PeTa effect—infrared characteristic radiation under first order phase transitions, especially the crystallization of melts and the deposition and condensation of vapours/gases. The PeTa effect describes the transient radiation that a particle (i.e., atom, molecule or/and cluster) emits during a t...
This paper presents new experimental evidence of the PeTa effect—infrared characteristic radiation under first order phase transitions, especially the crystallization of melts and the deposition and condensation of vapours/gases. The PeTa effect describes the transient radiation that a particle (i.e., atom, molecule or/and cluster) emits transient...
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... Phase-change radiation, while still not a generally accepted or recognized concept, is not a new idea; various investigators have reported on it for several decades. While the exact origin of the idea seems uncertain, it is claimed by Xie et al., [6] that Perel'man, who later published theories on it [7], suggested this kind of unusual enhanced absorption as early as the 1960 s; he proposed an electronic-state transition theory in 1971 [7]. Later the phrase "phase transition radiation" was introduced in the literature. ...
Infrared radiation associated with vapor-liquid phase transition of water is investigated using a suspension of cloud droplets and mid-IR (3-5 µm) radiation absorption measurements. Recent measurements and Monte Carlo modeling performed at 60°C and 1 atm resulted in an interfacial radiative phase-transition probability of 5E-8 and a corresponding surface absorption efficiency of 3 to 4%, depending on wavelength. In this paper the measurements and modeling have been extended to 75°C in order to examine the effect of temperature on water's liquid-vapor phase-change radiation. It was found that the temperature dependence of the previously proposed phase-change absorption theoretical framework by itself was insufficient to account for observed changes in radiation absorption without a change in cloud droplet number density. Therefore the results suggest a strong temperature dependence of cloud condensation nuclei (CCN) concentration, i.e., CCN increasing approximately a factor of two from 60°C to 75°C at near saturation conditions. The new radiative phase-transition probability is decreased slightly to 3E-8. Theoretical results were also calculated at 50°C in an effort to understand behavior at conditions closer to atmospheric. The results suggest that accounting for multiple interface interactions within a single droplet at wavelengths in atmospheric windows (where anomalous IR radiation is often reported) will be important. Modeling also suggests that phase-change radiation will be most important at wavelengths of low volumetric absorption, i.e., atmospheric windows such as 3-5 µm and 8-10 µm, and for water droplets smaller than stable cloud droplet sizes (< 20 µm diameter), where surface effects become relatively more important. This could include unactivated, hygroscopic aerosol particles (not CCN) that have absorbed water and are undergoing dynamic evaporation and condensation. This mechanism may be partly responsible for water vapor's IR continuum absorption in these atmospheric windows.
It is difficult and costly to accurately measure the spectral and spatial distributions of the infrared radiation signature of a high altitude aircraft’s surface at relatively low temperatures. To reduce the experimental cost, simulated experimental measurement on the ground is usually made to measure its infrared signature. However, there are three main difficulties in the ground measurement: (1) it is difficult to simulate the temperature at high altitude which is much lower than the temperature near the ground; (2) it is difficult to accurately measure the infrared signature of a low temperature surface on the ground; and (3) it is difficult to measure the infrared signature of a prototype aircraft surface. To solve these problems, a ground experimental simulation method to obtain the infrared signature of a high altitude aircraft’s surface is developed, which makes it possible to use a scale model (scale factor M) at relatively higher temperature (n times the temperature of the aircraft’s surface) to experimentally simulate the infrared signature of the actual aircraft’s surface. The results show that the integrated radiation intensity in the wavelength band between λ1 and λ2 of an original flying aircraft’s surface at a temperature range from T1 to T2 is equal to ɛ¯λ1-λ2,T1-T2ɛ¯λ1/n-λ2/n,nT1-nT2M2n4 times the integrated radiation intensity in the wavelength band between λ1/n and λ2/n of the scale test surface model on the ground at a temperature range from nT1 to nT2.
Infrared radiation associated with vapor-liquid phase transition of water is investigated using a suspension of cloud droplets and mid-infrared (IR) (3-5 mu m) radiation absorption measurements. Recent measurements and Monte Carlo (MC) modeling performed at 60 degrees C and 1 atm resulted in an interfacial radiative phase-transition probability of 5 x 10(-8) and a corresponding surface absorption efficiency of 3-4%, depending on wavelength. In this paper, the measurements and modeling have been extended to 75 degrees C in order to examine the effect of temperature on water's liquid-vapor phase-change radiation. It was found that the temperature dependence of the previously proposed phase-change absorption theoretical framework by itself was insufficient to account for observed changes in radiation absorption without a change in cloud droplet number density. Therefore, the results suggest a strong temperature dependence of cloud condensation nuclei (CCN) concentration, i.e., CCN increasing approximately a factor of two from 60 degrees C to 75 degrees C at near saturation conditions. The new radiative phase-transition probability is decreased slightly to 3 x 10(-8). Theoretical results were also calculated at 50 degrees C in an effort to understand behavior at conditions closer to atmospheric. The results suggest that accounting for multiple interface interactions within a single droplet at wavelengths in atmospheric windows (where anomalous IR radiation is often reported) will be important. Modeling also suggests that phase-change radiation will be most important at wavelengths of low volumetric absorption, i.e., atmospheric windows such as 3-5 mu m and 8-10 mu m, and for water droplets smaller than stable cloud droplet sizes (<20 mu m diameter), where surface effects become relatively more important. This could include unactivated, hygroscopic aerosol particles (not CCN) that have absorbed water and are undergoing dynamic evaporation and condensation. This mechanism may be partly responsible for water vapor's IR continuum absorption in these atmospheric windows.
This paper considers a new physical phenomenon - infrared characteristic radiation (IRCR) at first order phase transitions (melt crystallization, and vapor condensation and/or deposition). Experimental results are analyzed in terms of their correspondence to the theoretical model. This model is based on the assertion that the particle’s (atom’s, molecule’s, or cluster’s) transition from a higher energetic level in a meta-stable or unstable phase (vapor or liquid) to a lower level in a stable phase (liquid or crystal) can emit one or more photons. The energy of these photons depends on the latent energy of the phase transition and the character of bonds formed by the particles in the new phase. For all investigated substances, this energy falls in the infrared range. This is a reason why the radiation is named as IRCR–infrared characteristic radiation. Many sources of the infrared radiation recorded in the atmosphere seem to be a result of crystallization, condensation and/or sublimation of water during fog and cloud formation. Thus, the effect under investigation must play a very important role in atmospheric phenomena: it is one of the sources of Earth’s cooling; formation of hailstorm clouds is accompanied by intensive characteristic infrared radiation that could be used for process characterization and meteorological warnings. IRCR seems to explain red color of Jupiter. It can be used for atmospheric energy accumulation, and, thus, together with wind, falling water, solar and geothermal energies, IRCR makes available the fifth source of ecologically pure energy.
Keywords: crystal growth from melt, crystal growth from vapor, vapor Trouton’s rule, atmospheric energy accumulation
PACS: 92.70.Cp, 78.30.Er DOI: 10.7498/aps.62.079203
