scholarly journals The mechanism of surface cooling by a horizontal layer of liquid evaporating at low reduced pressures

AIP Advances ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 015341
Author(s):  
V. I. Zhukov ◽  
A. N. Pavlenko
2018 ◽  
Author(s):  
Jeongmoon Park ◽  
Jorge L. Alvarado ◽  
Leonardo P. Chamorro ◽  
Charles P. Marsh

2019 ◽  
Vol 943 (1) ◽  
pp. 68-75
Author(s):  
S.G. Pugacheva ◽  
E.A. Feoktistova ◽  
V.V. Shevchenko

The article presents the results of astrophysical studies of the Moon’s reflected and intrinsic radiation. We studied the intensity of the Moon’s infrared radiation and, thus, carried out a detailed research of the brightness temperature of the Moon’s visible disc, estimated the thermal inertia of the coating substance by the rate of its surface cooling, and the degree of the lunar soil fragmentation. Polarimetric, colorimetric and spectrophotometric measurements of the reflected radiation intensity were carried out at different wavelengths. In the article, we present maps prepared based on our measurement results. We conducted theresearch of the unique South Pole – Aitken basin (SPA). The altitude profiles of the Apollo-11 and Zond-8 spacecrafts and the data of laser altimeters of the Apollo-16 and Apollo-15 spacecrafts were used as the main material. Basing upon this data we prepared a hypsometric map of SPA-basing global relief structure. A surface topography map of the Moon’s Southern Hemisphere is given in the article. The topography model of the SPA topography surface shows displacement centers of the altitude topographic rims from the central rim. Basing upon the detailed study of the basin’s topography as well as its “depth-diameter” ratio we suggest that the basin originated from the impact of a giant cometary body from the Orta Cloud. In our works, we consider the Moon as a part of the Earth’s space infrastructure. High growth rates of the Earth’s population, irrational nature management will cause deterioration of scarce natural resources in the near future. In our article, we present maps of the natural resources on the Moon pointing out the most promising regions of thorium, iron, and titanium. Probably in 20 or 40 years a critical mining level of gold, diamonds, zinc, platinum and other vital rocks and metals will be missing on the Earth.


2019 ◽  
Vol 45 (6) ◽  
pp. 527-536 ◽  
Author(s):  
A. V. Strikovskiy ◽  
S. V. Korobkov ◽  
M. E. Gushchin ◽  
A. A. Evtushenko ◽  
I. Yu. Zudin

Author(s):  
C.-L. Ng ◽  
K. A. Sallam

The deformation of laminar liquid jets in gaseous crossflow before the onset of primary breakup is studied motivated by its application to fuel injection in jet afterburners and agricultural sprays, among others. Three crossflow Weber numbers that represent three different liquid jet breakup regimes; column, bag, and shear breakup regimes, were studied at large liquid/gas density ratios and small Ohnesorge numbers. In each case the liquid jet was simulated from the jet exit and ended before the location where the experimental data indicated the onset of breakup. The results show that in column and bag breakup, the reduced pressures along the sides of the jet cause the liquid to move to the sides of the jet and enhance the jet deformation. In shear breakup, the flattened upwind surface pushes the liquid towards the two sides of the jet and causing the gaseous crossflow to separate near the edges of the liquid jet thus preventing further deformation before the onset of breakup. It was also found out that in shear breakup regime, the liquid phase velocity inside the liquid jet was large enough to cause onset of ligament formation along the jet side, which was not the case in the column and bag breakup regimes. In bag breakup, downwind surface waves were observed to grow along the sides of the liquid jet triggered a complimentary experimental study that confirmed the existence of those waves for the first time.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dongdong Wang ◽  
Bin Zhu ◽  
Hongbo Wang ◽  
Li Sun

AbstractIn this study, we designed a sensitivity test using the half number concentration of sulfate in the nucleation calculation process to study the aerosol-cloud interaction (ACI) of sulfate on clouds, precipitation, and monsoon intensity in the summer over the eastern China monsoon region (ECMR) with the National Center for Atmospheric Research Community Atmosphere Model version 5. Numerical experiments show that the ACI of sulfate led to an approximately 30% and 34% increase in the cloud condensation nuclei and cloud droplet number concentrations, respectively. Cloud droplet effective radius below 850 hPa decreased by approximately 4% in the southern ECMR, while the total liquid water path increased by 11%. The change in the indirect radiative forcing due to sulfate at the top of the atmosphere in the ECMR during summer was − 3.74 W·m−2. The decreased radiative forcing caused a surface cooling of 0.32 K and atmospheric cooling of approximately 0.3 K, as well as a 0.17 hPa increase in sea level pressure. These changes decreased the thermal difference between the land and sea and the gradient of the sea-land pressure, leading to a weakening in the East Asian summer monsoon (EASM) and a decrease in the total precipitation rate in the southern ECMR. The cloud lifetime effect has a relatively weaker contribution to summer precipitation, which is dominated by convection. The results show that the ACI of sulfate was one possible reason for the weakening of the EASM in the late 1970s.


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