scholarly journals Comparison of various models of supercooled water loss factor with experimental data at microwaves

Author(s):  
G. S. Bordonskiy ◽  
A. O. Orlov

An improved formula for the supercooled water loss factor at frequencies 10…180 GHz in the temperature range 0 ... –70 °C is presented. The formula based on the experimental data obtained by the authors on measurements of attenuation in the pore water of silicate materials. The formula contains two terms connected the Debye dependence of the loss factor on frequency and temperature, and non-Debye, determined by the influence of the second critical point of water. Comparison of the proposed formula and the model formulas of other authors is carried out. A significant discrepancy between the calculation results (at several times) of the loss factor at frequencies above 100 GHz and temperatures below –30 °C has been founded. The model based on the measurements provides the most adequate representation of the behavior of the loss factor with an error of ~ 30% in the area of deep supercooling of water and in the upper part of the studied frequency band.

2020 ◽  
pp. 56-58
Author(s):  
P.V. Gubarev ◽  
D.V. Glazunov ◽  
V.G. Ruban ◽  
A.S. Shapshal

The thermal calculation of the locomotive traction engine collector is proposed. The equations of the heat balance of its elements are obtained taking into account the cooling air. The calculation results and experimental data of thermal imaging control are presented. Keywords: traction electric motor, collector, thermal calculation, thermal imaging control. [email protected]


2013 ◽  
Vol 671-674 ◽  
pp. 1761-1765
Author(s):  
Yong Liu ◽  
Chun Ming Song ◽  
Song Lin Yue

In order to get mechanical properties ,some RPC samples with 5% steel fiber are tested, many groups data were obtained such as compressive strength, shear strength and fracture toughness. And a group of tests on RPC with 5% steel-fiber under penetration were also conducted to validate the performance to impact. The penetration tests are carried out by the semi-AP projectiles with the diameter of 57 mm and earth penetrators with the diameter of 80 mm, and velocities of the two kinds of projectiles are 300~600 m/s and 800~900 m/s, respectively. By contrast between the experimental data and the calculation results of C30 reinforced concrete by using experiential formula under penetration, it shows that the resistance of steel-fiber RPC to penetration is 3 times as that of general C30 reinforced concrete.


2018 ◽  
Vol 197 ◽  
pp. 09005
Author(s):  
Bregas Siswahjono Tatag Sembodo ◽  
Hary Sulistyo ◽  
Wahyudi Budi Sediawan ◽  
Mohammad Fahrurrozi

Corncobs are potentially processed into bio-oil through thermochemical liquefaction processes. It is difficult to construct kinetics models based on the compounds involved in the reaction. It would be made four kinetic models based on four reaction products, i.e., solids, bio-oil, gas and volatile products. The purposes of the study were to seek kinetics model of thermochemical liquefaction of corncobs in ethanol-water solution and to study the effect of ethanol concentration. The experiment of liquefaction processes of corncobs in ethanol-water solution using sodium carbonate catalyst was performed in the 150 ml autoclave equipped with a magnetic stirrer in the temperature up to 280°C. Four kinetic models were applied to predict the yield of four reaction product lumps. The calculation results were compared to the experimental data. Compared to the others, model 4 was the most realistic and closely matching to the experimental data. In model 4 the reaction mechanism was assumed that biomass (corncobs) first decomposed into bio-oil, followed by decomposition of bio-oil into volatile products reversibly and, finally, volatile products decomposed into gaseous products. The yield of bio-oil increased from 42.05% to 54.93% by increasing to ethanol concentration of 0% to 40%.


2019 ◽  
pp. 88-93
Author(s):  
O.R. Trofymenko ◽  
А.V. Nosovsky ◽  
V.I. Gulik

Modeling of the neutron-physical characteristics of the Kyoto University KUCA subcritical facility was conducted using the Monte Carlo Serpent code. The effective multiplication factors for the critical experiments of the series II on the KUCA research subcritical facility were calculated. The presented calculation results were compared with the experimental results and the results of the calculations made using the Monte Carlo codes MCNP6 and KENO-VI.


2020 ◽  
pp. 5-11
Author(s):  
Vladimir Kurteyev ◽  
◽  
Boris Mozerov ◽  

There is studied the problems experiment modeling under impact of torn vane with turbojet fan case. There are outlined shortcomings of equipment for plane and cylindrical model cases testing. There is indicated the difference between calculation results and experimental data for metals plane models. There are indicated diagram laboratory experiment installation on basic pressurized balloons for testing metals plane models. There are calculated parameters of metals plane model with the point of views criterion modeling.


1999 ◽  
Vol 17 (2) ◽  
pp. 293-298
Author(s):  
A.V. BESSARAB ◽  
S.A. BEL'KOV ◽  
P.D. GASPARYAN ◽  
N.V. ZHIDKOV ◽  
A.V. KUNIN ◽  
...  

Measurements of spectral and energy X-ray characteristics of almost transparent Fe plasma produced by laser radiation inside the inverted-corona targets have been made at ISKRA-5 facility. The targets were spherical plastics cavities with 2-mm diameter and 4.6-μm thickness covered from inside with Fe layer 0.25-μm thickness. X-ray spectrum, X-ray total energy, and the energy of a HeαFe resonance line have been measured. Experimental data and calculation results are collated.


2018 ◽  
Vol 141 (2) ◽  
Author(s):  
Hailong Cui ◽  
Huan Xia ◽  
Dajiang Lei ◽  
Xinjiang Zhang ◽  
Zhengyi Jiang

In this paper, a calculation method based on matlab partial differential equations (PDE) tool is proposed to investigate the static characteristics of aerostatic spherical bearings. The Reynolds equation of aerostatic spherical bearings is transformed into a standard elliptic equation. The effects of geometric parameters and operational conditions on the film pressure, bearing film force, and stiffness are studied. The axial and radial eccentricities result in different film pressure distributions; the bearing film force and stiffness are significantly influenced by geometric parameters and operational conditions. The relative optimal parameters are confirmed based on the calculation results. A comparison between the numerical and experimental results is also presented. The highest relative error between the numerical results and the experimental data is 11.3%; the calculation results show good agreements with the experimental data, thus verifying the accuracy of the calculation method used in this paper.


Akustika ◽  
2021 ◽  
pp. 100-106
Author(s):  
sergey Timushev ◽  
Alexey Yakovlev ◽  
Petr Moshkov

The problem of simulation the noise generated during the operation of the propeller is considered. Calculation methods are described and numerical simulation of the noise of a light aircraft propeller by the acoustic-vortex method is performed. The results of numerical modeling of the tonal components of the propeller noise when operating under static conditions are compared with experimental data and calculation results based on a semiempirical model.


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