scholarly journals Discussion of a Coupled Strength Attenuation Model for GFRP Composites in Hydrothermal Environments

2016 ◽  
Vol 2016 ◽  
pp. 1-6
Author(s):  
Wei Chen ◽  
Yongxin Yang ◽  
Biao Li
Keyword(s):  
Experimental Data ◽  
Coupled Model ◽  
Gfrp Composites ◽  
New Model ◽  
Attenuation Model ◽  
Fiber Reinforced Polymer Composites ◽  
Calculation Results ◽  
Temperature Parameter ◽  
Attenuation Models ◽  
Hydrothermal Environments

The existing attenuation models for the durability of FRP (fiber-reinforced polymer) composites in hydrothermal environments were compared, and a new coupled strength attenuation model with a temperature parameter was proposed in this paper. A series of durability experiments on GFRP sheets in hydrothermal environments were conducted to validate the accuracy and rationality of the new model. A comparison between experimental data and the calculation results of the coupled model indicated that the new model can fit better with the experimental data and effectively reflect the convergence phenomenon in the strength attenuation of GFRP in hydrothermal environments. With a temperature parameter included, the new model can better predict the service life of GFRP composites at different aging temperatures. According to the coupled attenuation model proposed in this paper, a concept and calculation method of the slow-aging time point are put forward, which can be convenient for the evaluation and design of GFRP structures with long-term durability.

scholarly journals High-precision Online Prediction Model of Plate Crown Based on Multi-factor Interaction Mechanism

2020 ◽  
Author(s):  
Li ZhiQiang ◽  
YuanMing Liu ◽  
Tao Wang ◽  
Ignatov Aleksei Vladimirovih ◽  
QingXue Huang
Keyword(s):  
Prediction Model ◽  
High Precision ◽  
Prediction Models ◽  
Interaction Mechanism ◽  
Coupled Model ◽  
Correction Coefficient ◽  
New Model ◽  
Calculation Results ◽  
Factor Interaction ◽  
Very High

Abstract The crown is a key quality index of strip and plate. Up to now, many plate crown prediction models have been established, however, the calculation accuracy of these traditional models is not very high. This is because these models only consider the effect of various influencing factors on the outlet plate crown under the basic process parameters, but these factors are not independent of each other. Therefore, in order to improve the accuracy of the plate crown prediction model, a high-precision prediction model of plate crown is established by introducing the evaluation coefficient that represents the influence of single factor on plate crown and the correction coefficient that represents the effect of factor a on the evaluation coefficient of factor b. This paper takes the steel SPHC as an example, calculates the plate crown without considering the correction coefficient and the plate crown considering the correction coefficient. Then, the two calculation results are compared with the calculation results of the coupled model and the accuracy of the new model is improved after considering the correction coefficient. In general, compared with the traditional crown prediction model, the accuracy of the new model is greatly improved.

Refined thermal calculation of the locomotive heat engine collector

2020 ◽  
pp. 56-58
Author(s):  
P.V. Gubarev ◽  
D.V. Glazunov ◽  
V.G. Ruban ◽  
A.S. Shapshal
Keyword(s):  
Experimental Data ◽  
Electric Motor ◽  
Heat Balance ◽  
Thermal Imaging ◽  
Heat Engine ◽  
Thermal Calculation ◽  
Calculation Results ◽  
Cooling Air ◽  
The Heat Balance ◽  
Traction Electric Motor

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]

Tests on Mechanical Properties and Anti-Penetration Performance of Steel-Fiber Reactive Powder Concrete

2013 ◽  
Vol 671-674 ◽  
pp. 1761-1765
Author(s):  
Yong Liu ◽  
Chun Ming Song ◽  
Song Lin Yue
Keyword(s):  
Experimental Data ◽  
Mechanical Properties ◽  
Fracture Toughness ◽  
Compressive Strength ◽  
Reinforced Concrete ◽  
Steel Fiber ◽  
Reactive Powder Concrete ◽  
Calculation Results ◽  
Reactive Powder ◽  
Penetration Tests

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.

High-enthalpy, water-cooled and thin-walled ICP sources characterization and MHD optimization

2008 ◽  
Vol 74 (3) ◽  
pp. 391-429 ◽  
Author(s):  
G. HERDRICH ◽  
D. PETKOW
Keyword(s):  
Experimental Data ◽  
Magnetic Pressure ◽  
Maximum Pressure ◽  
Published Data ◽  
Space Vehicles ◽  
Maximum Plasma ◽  
Plasma Power ◽  
New Model ◽  
High Enthalpy ◽  
Lorentz Forces

AbstractThe development of the inductively driven plasma wind tunnel PWK3, which enables the electrodeless generation of high-enthalpy plasmas for the development of heat shield materials required for space vehicles performing entry manoeuvres in the atmospheres of Venus, Earth and Mars, is described. The facility with its modular inductive plasma generators allows operation with gases such as carbon dioxide, air, oxygen and nitrogen and was qualified for thermal plasma powers up to 60 kW. Previously developed models for determining plasma properties and plasma source related characteristics enable a maximum plasma power in combination with long operational periods using different operational gases and gas mixtures. This is achieved by an optimization using the optimum operational frequency, a minimization of field losses using very thin plasma tube wall thicknesses and the successful application of MHD effects. Based on the solved cylinder problem for ICPs, a one-dimensional model for radial Lorentz forces and magnetic pressure has been developed. Here, a synthesis of previously published data and works is made where the new algebraic model for the calculation of Lorentz forces and magnetic pressures in an ICP was used and applied to experimental data. In addition, results from the model using the experimental data are shown to be consistent and, in addition, a comparison with a simpler model based on the well-known exponential approach for ICPs showed that the simpler model is covered without fail by the new model. The new model also states that there is a maximum of the Lorentz forces over the damping parameter d/δ (plasma diameter divided by skin depth) which almost corresponds with the position of the maximum plasma power of the cylindric model for ICPs. For the magnetic pressure the position of the maximum pressure is identical to the value for d/δ for the maximum plasma power.

scholarly journals A New Model Approach for Convective Wall Heat Losses in DQMOM-IEM Simulations for Turbulent Reactive Flows

2018 ◽  
Vol 141 (5) ◽  
Author(s):  
Yeshaswini Emmi ◽  
Andreas Fiolitakis ◽  
Manfred Aigner ◽  
Franklin Genin ◽  
Khawar Syed
Keyword(s):  
Experimental Data ◽  
Heat Losses ◽  
Reacting Flow ◽  
Jet Flame ◽  
New Model ◽  
Turbulent Reactive Flows ◽  
Novel Method ◽  
The One ◽  
The Impact ◽  
Model Approach

A new model approach is presented in this work for including convective wall heat losses in the direct quadrature method of moments (DQMoM) approach, which is used here to solve the transport equation of the one-point, one-time joint thermochemical probability density function (PDF). This is of particular interest in the context of designing industrial combustors, where wall heat losses play a crucial role. In the present work, the novel method is derived for the first time and validated against experimental data for the thermal entrance region of a pipe. The impact of varying model-specific boundary conditions is analyzed. It is then used to simulate the turbulent reacting flow of a confined methane jet flame. The simulations are carried out using the DLR in-house computational fluid dynamics code THETA. It is found that the DQMoM approach presented here agrees well with the experimental data and ratifies the use of the new convective wall heat losses model.

scholarly journals Kinetics study on non-isothermal thermochemical liquefaction of corncobs in ethanol-water solution: Effect of ethanol concentration

2018 ◽  
Vol 197 ◽  
pp. 09005
Author(s):  
Bregas Siswahjono Tatag Sembodo ◽  
Hary Sulistyo ◽  
Wahyudi Budi Sediawan ◽  
Mohammad Fahrurrozi
Keyword(s):  
Experimental Data ◽  
Kinetic Models ◽  
Ethanol Concentration ◽  
Water Solution ◽  
Reaction Products ◽  
Gaseous Products ◽  
Bio Oil ◽  
Volatile Products ◽  
Calculation Results ◽  
Oil Gas

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%.

scholarly journals USE OF THE MONTE CARLO SERPENT CODE FOR MODELING THE SECOND SERIES OF EXPERIMENTAL DATA OF KUCA SUBCRITICAL INSTALLATION

2019 ◽  
pp. 88-93
Author(s):  
O.R. Trofymenko ◽  
А.V. Nosovsky ◽  
V.I. Gulik
Keyword(s):  
Experimental Data ◽  
Monte Carlo ◽  
Physical Characteristics ◽  
Experimental Results ◽  
Calculation Results ◽  
Effective Multiplication

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.

scholarly journals THE PROBLEMS EXPERIMENT MODELING UNDER IMPACT OF TORN VANE WITH TURBOJET FAN CASE

2020 ◽  
pp. 5-11
Author(s):  
Vladimir Kurteyev ◽  
◽  
Boris Mozerov ◽  
Keyword(s):  
Experimental Data ◽  
Laboratory Experiment ◽  
Plane Model ◽  
Cylindrical Model ◽  
Calculation Results ◽  
The Difference

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.

scholarly journals Research of friction characteristics on the hydraulic transportation in inclined slurry-pipe

2020 ◽  
Vol 198 ◽  
pp. 01030
Author(s):  
Wang Tieli
Keyword(s):  
Experimental Data ◽  
Momentum Transfer ◽  
Interaction Mechanism ◽  
Hydraulic Gradient ◽  
Solid Particles ◽  
Friction Loss ◽  
Acceleration Time ◽  
New Model ◽  
Inclined Pipe ◽  
Inclined Pipes

By analyzing the momentum transfer and velocity both of solid particles and water over the acceleration time of solid particles, as well as interaction mechanism between water and solid particals, a new model is proposed to predict friction loss for setting slurry flow in inclined pipe. The hydraulic gradient formula for inclined pipes summarized by the author is confirmed by a large amount of experimental data. The results show that the deviation between the theoretical value of the model proposed by the author and the measured value is not more than 13.33%, which is the smallest among all reports.

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