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Online since: June 2023
Authors: Teresa Miranda, Jorge Padrão, Andrea Zille, Joana Faria
The same letters are given to data not different statistically.
The same letters are given to data not different statistically.
The same letters are given to data not different statistically.
The same letters are given to data not different statistically.
The same letters are given to data not different statistically.
The same letters are given to data not different statistically.
The same letters are given to data not different statistically.
The same letters are given to data not different statistically.
The same letters are given to data not different statistically.
Online since: October 2013
Authors: Xue Jing Zhang, Zhen Tao Fei
The internal flow fields of liquids in space between casing and rotating disk have been obtained by using CFD.The curves of shear stress on the disk and static pressure on casing wall against radius are also gained in various viscosity and different leakage conditions.The results indicate that the shear stress is influenced significantly by the leakage in the space.The shear stress on the disk decreases with the increase of leakage,especially in small radius.However, the reduction rate of stress gets smaller with the increasing of liquid viscosity.The greater the viscosity is, the higher the shear stress is.The growth of shear stress along the direction of radius is greater than in small viscosity.
The pressure distribution of shell wall compared with the experimental data Using the turbulence model of ,the static pressure coefficient of the shell calculated by Fluent almost coincides with the theoretical calculation results in refrence [4] and is also consistent with the experimental data in the same refrence very well (Figure 5)when the leakage is zero and the liquid viscosity is dynamic viscosity of water 0.001Pa.s.When the viscosity increases to 0.1Pa.s,the calculation is relatively consistent with the experimental results.This indicates that the theoretical value is consistent with the experimental value when the viscosity is not too high, so the flow model used in the calculation is correct,the calculation is indeed convergence,the calculation results by Fluent are credible.When the viscosity is 1.0Pa.s, the Liquid viscosity is relatively great difference with the actual viscosity of water,viscosity has a great effect on the pressure distribution and a large deviation with
From the table we can see that the smaller the radius is,the more the reduction of shear stress is,the higher the viscosity,the less the decreasing of shear stress.
Conclusions (1) The influence of leakage on shear stress of disk wall is significant,especially in small radius,shear stress reduction rate of the rotating disk wall is relatively large with the increasing of leakage ,but the reduction rate of shear stress of the wall decreases with increasing of viscosity
The pressure distribution of shell wall compared with the experimental data Using the turbulence model of ,the static pressure coefficient of the shell calculated by Fluent almost coincides with the theoretical calculation results in refrence [4] and is also consistent with the experimental data in the same refrence very well (Figure 5)when the leakage is zero and the liquid viscosity is dynamic viscosity of water 0.001Pa.s.When the viscosity increases to 0.1Pa.s,the calculation is relatively consistent with the experimental results.This indicates that the theoretical value is consistent with the experimental value when the viscosity is not too high, so the flow model used in the calculation is correct,the calculation is indeed convergence,the calculation results by Fluent are credible.When the viscosity is 1.0Pa.s, the Liquid viscosity is relatively great difference with the actual viscosity of water,viscosity has a great effect on the pressure distribution and a large deviation with
From the table we can see that the smaller the radius is,the more the reduction of shear stress is,the higher the viscosity,the less the decreasing of shear stress.
Conclusions (1) The influence of leakage on shear stress of disk wall is significant,especially in small radius,shear stress reduction rate of the rotating disk wall is relatively large with the increasing of leakage ,but the reduction rate of shear stress of the wall decreases with increasing of viscosity
Online since: December 2014
Authors: Rafael Farinassi Mendes, Ticyane Pereira Freire, Stefânia Lima Oliveira, Lourival Marin Mendes
Statistical Analysis
For statistical analysis of the data, one experiment in a completely randomized design was considered.
In general, the data obtained in this study is in agreement with those reported in the literature.
Thus, in comparison with the published data, the panels evaluated in the present study showed consistent average values.
Overall, compared with the data available in the literature, the panels evaluated in this study showed consistent average internal bond values.
Compared with the data reported in the literature, the panels evaluated in this work showed consistent average MOR and MOE values.
In general, the data obtained in this study is in agreement with those reported in the literature.
Thus, in comparison with the published data, the panels evaluated in the present study showed consistent average values.
Overall, compared with the data available in the literature, the panels evaluated in this study showed consistent average internal bond values.
Compared with the data reported in the literature, the panels evaluated in this work showed consistent average MOR and MOE values.
Online since: July 2017
Authors: Antônio Augusto Couto, Danieli Aparecida Pereira Reis, Antônio Jorge Abdalla, Jorge Otubo, Francisco Piorino Neto, Adriano Gonçalves Reis
Data available on the mechanical properties of maraging steel at elevated temperature are very scarce.
Specialized applications of the steel, such as the motor case of a solid propellant rocket, occasionally demand short-time exposures at high temperatures and it is desirable to have data on the hot tensile behavior of the material during such service conditions [5-8].
Software Blue Hill 2.6 was used for data acquisition.
This reduction in ductility can be also shown by fractography analysis.
However, the plasma nitriding treatment decreased the ductility (reduction in area) by 36% as a result of premature cracking of the compound layer.
Specialized applications of the steel, such as the motor case of a solid propellant rocket, occasionally demand short-time exposures at high temperatures and it is desirable to have data on the hot tensile behavior of the material during such service conditions [5-8].
Software Blue Hill 2.6 was used for data acquisition.
This reduction in ductility can be also shown by fractography analysis.
However, the plasma nitriding treatment decreased the ductility (reduction in area) by 36% as a result of premature cracking of the compound layer.
Online since: January 2019
Authors: Kai Lin, Wen Hong Liu, Yan Long, Da Shun Qin, Zhi Yong Pan
Test equipment for studying the high temperature strength and deformation of metal materials should include three systems: loading system, heating and temperature control system, data measurement and recording system.
According to the statistical principle of data[9], three samples were used for each temperature in this test to determine the above properties.
Tensile test at room temperature, 100℃, 150℃, 200℃, 250℃, three data were obtained at each test temperature and averaged.
Three test data were obtained at each test temperature.
Three test data were obtained at each test temperature.
According to the statistical principle of data[9], three samples were used for each temperature in this test to determine the above properties.
Tensile test at room temperature, 100℃, 150℃, 200℃, 250℃, three data were obtained at each test temperature and averaged.
Three test data were obtained at each test temperature.
Three test data were obtained at each test temperature.
Online since: June 2014
Authors: Jia Bin Wu, Jian Cheng Zhang, He Xiang Zheng, Xue Song Cao
Agreement is good between simulated by SIRMOD model and measured values through field trials the measured data of water flow advance and regression process, and indicating with SIRMOD model can simulate border irrigation process.
The times of irrigation in the whole growth period of wheat are four in 2012 year, and the border field parameters calculated by measured field irrigation values are shown in Table 1, Soil parameters are given in the table is according to the average value of four irrigation test data, which can basically reflect soil infiltration and field surface water resistance characteristics.
Simulation and analysis of land roughness effects on irrigation efficiency Irrigation experiment data of border irrigation are the basic samples in the research of land roughness effects on irrigation efficiency and the parameters according to Table 1.
The simulated values are in good agreement with the measured values by SIRMOD model to simulate water flow advance and recession process using field measured data in condition leveling precision is about 4.93cm and the land roughnes is 0.130 from Figure 1.
and regression becomes uneven, so irrigation efficiency significant reduction with the field surface roughness increases.
The times of irrigation in the whole growth period of wheat are four in 2012 year, and the border field parameters calculated by measured field irrigation values are shown in Table 1, Soil parameters are given in the table is according to the average value of four irrigation test data, which can basically reflect soil infiltration and field surface water resistance characteristics.
Simulation and analysis of land roughness effects on irrigation efficiency Irrigation experiment data of border irrigation are the basic samples in the research of land roughness effects on irrigation efficiency and the parameters according to Table 1.
The simulated values are in good agreement with the measured values by SIRMOD model to simulate water flow advance and recession process using field measured data in condition leveling precision is about 4.93cm and the land roughnes is 0.130 from Figure 1.
and regression becomes uneven, so irrigation efficiency significant reduction with the field surface roughness increases.
Online since: February 2025
Authors: Yuriy Tsapko, Oleksii Tsapko, Ruslan Likhnyovskyi, Vitalii Kovalenko
Calculations of the 1D, steady, adiabatic, laminar burning velocity for these refrigerants with air or oxygen-enriched air indicate reasonable agreement with experimental data from the literature when the burning velocity is above 10 cm/s.
However, no experimental data are available at combustion temperatures.
The conventional transition state theory has been tested against the rate data obtained by the QCT method and was found to overestimate not only the rate coefficients but also the activation energies.
Experimental data on extinguishing concentrations during extinguishing of n-heptane using their combinations are shown in Fig. 3 and 4.
The results of the experimental studies conducted can be used as input data for the technical and economic justification of the choice of the quantitative ratio of the inert gas and the combustion inhibitor in case of their joint application for the purpose of preventing and extinguishing fires.
However, no experimental data are available at combustion temperatures.
The conventional transition state theory has been tested against the rate data obtained by the QCT method and was found to overestimate not only the rate coefficients but also the activation energies.
Experimental data on extinguishing concentrations during extinguishing of n-heptane using their combinations are shown in Fig. 3 and 4.
The results of the experimental studies conducted can be used as input data for the technical and economic justification of the choice of the quantitative ratio of the inert gas and the combustion inhibitor in case of their joint application for the purpose of preventing and extinguishing fires.
Online since: October 2016
Authors: Salah Rahimi, Paul Blackwell, Saber Khayatzadeh
A significant degradation was observed in elastic modulus (up to 50% reduction)with increased plastic deformation.
True stress and true strain were computed from engineering data set, assuming that the sample’s volume remains constant after deformation in tension.As shown, the material during the loading-unloading process shows a similar behavior to that of the standard tensile test throughout the experiment.
This reduction can be separated into two segments: A and B.
Segment A is mainly the result of a reduction in the elastic modulus.
A B a)b) Fig. 4: Magnified views of unloading data for a sampleat 0°(i.e. aligned with RD),showing the nonlinear recovery followingthe unloading. a) unloading-loading curve for loop 4 to 5.
True stress and true strain were computed from engineering data set, assuming that the sample’s volume remains constant after deformation in tension.As shown, the material during the loading-unloading process shows a similar behavior to that of the standard tensile test throughout the experiment.
This reduction can be separated into two segments: A and B.
Segment A is mainly the result of a reduction in the elastic modulus.
A B a)b) Fig. 4: Magnified views of unloading data for a sampleat 0°(i.e. aligned with RD),showing the nonlinear recovery followingthe unloading. a) unloading-loading curve for loop 4 to 5.
Online since: October 2018
Authors: Zalim N. Deunezhev
It is shown that an increase in the thermal conductivity of the matrix due to fillers provides a reduction in the thermal load on the polymer binder.
As initial data in numerical experiments, the parameters of the system characteristic for the conditions of diamond grinding wheels operating on a bakelite binder were adopted (Table 1).
The thermal load on the system was set from the condition that the temperatures in the system correspond to known experimental data [1, 2].
It should be noted that when choosing a filler to reduce the thermal conductivity, other properties of the composition should not deteriorate, the complex of which should ensure a reduction in the specific consumption of diamonds, as the most important indicator of the performance of a diamond-abrasive tool.
As initial data in numerical experiments, the parameters of the system characteristic for the conditions of diamond grinding wheels operating on a bakelite binder were adopted (Table 1).
The thermal load on the system was set from the condition that the temperatures in the system correspond to known experimental data [1, 2].
It should be noted that when choosing a filler to reduce the thermal conductivity, other properties of the composition should not deteriorate, the complex of which should ensure a reduction in the specific consumption of diamonds, as the most important indicator of the performance of a diamond-abrasive tool.
Online since: March 2014
Authors: Masao Sakane, Takamoto Itoh, Hideyuki Kanayama, Masahiro Sakabe, Shu Li Liu, Takahiro Morishita, Norio Takeda
Thus, the agreement of data correlations between in strain and stress controlled tests in Fig. 3 (a) may be resulted from that the reduction in failure life is balanced with the additional hardening. [10,11]
On the other hand, fatigue limit in the circle loading test seems to be lower than that in the push-pull loading test.
In the figure, the bold solid line was drawn based on the data of push-pull loading test and the two thin lines show a factor of 2 band.
In this study, A is put to 3.5σB/E but B is determined to fit the life curve on data in push-pull loading test.
This figure shows a relative good correlation although the data in the lower strain level are plotted conservatively.
Failure life and its evaluation under the random multiaxial loading will be discussed more based on the experimental data which will be obtained.
In the figure, the bold solid line was drawn based on the data of push-pull loading test and the two thin lines show a factor of 2 band.
In this study, A is put to 3.5σB/E but B is determined to fit the life curve on data in push-pull loading test.
This figure shows a relative good correlation although the data in the lower strain level are plotted conservatively.
Failure life and its evaluation under the random multiaxial loading will be discussed more based on the experimental data which will be obtained.