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The accuracy of the rubber constitutive model characterizing experiment data has a crucial influence on the mechanical analysis of rubber structures. In this paper, a new improved hyperelastic constitutive model is proposed, and the model is derived into the stress-strain forms of uniaxial tension, equibiaxial tension and pure shear. Based on the experimental data of filled rubber, the material parameters of each deformation state are obtained by using the newly proposed rubber hyperelastic constitutive model, and the uniaxial tensile (UT), Equibiaxial tension (ET) and Pure shear (PS) specimens are simulated and calculated in the finite element software. the stress state of each finite element specimen is analyzed and the obtained simulation data are compared with the experimental data. It is found that the new model can accurately characterize the hyperelastic mechanical properties of the experimental specimens in different deformation states. At the same time, the reasons for the deviation from the experimental data in the process of plane tensile simulation are analyzed and explained comprehensively. The reliability and accuracy of the classical rubber constitutive relations of polynomial models and eight-chain model are studied. the results show that different hyperelastic models have different ability to describe the hyperelastic behavior in different deformation states. the hyperelastic constitutive model proposed in this paper can be easily embedded into finite element software and has the advantages of accurate results, few material parameters and simple testing.

This paper uses the ABAQUS finite element analysis software for modeling and nonlinear analysis of aircraft tires. Paper H44.5 × 16.5-21 aviation tires, The plastic material of the tire subjected to uniaxial stretching to obtain a rubber such as Young's modulus, Poisson's ratio of the material parameters. Uniaxial tensile test tests the tensile properties of the rubber, the use of large-scale numerical calculations and fitting analysis of the experimental data analysis software Matlab, Yeoh model mechanical parameters.

In UHF band, the effects of carbon black component on the dielectric properties of rubber composites are studied through experiments. The results show that the content of the carbon black have great effects on the dielectric properties of the composite rubber. The higher content of the carbon black in the rubber composite, the larger the permittivity and dielectric loss tangent. At the same time, the operating frequencies also have great influence on the dielectric properties of the rubber composite. In the UHF band, the permittivity and the dielectric loss tangent of the rubber composites decrease with frequency increasing.

The performance of the RFID tag which was implanted into the tire was studied. The shape of implanted RFID antenna, package form and the process of RFID implantation were given. In the same time, experiments were carried out to test the performance of RFID tag which implanted into the tire. The results show that: the read distance is shorten after implanted in the tire, the sidewall of the tire is the idea position for RFID tag implantation, and it can achieve good performance by changing the structure of the RFID antenna and improving implantation process.

Image segmentation technology is crucial for feature extraction. In this paper, the traditional thresholding method has been improved, and the optimal threshold segmentation method is proposed by combining the iterative algorithm and mathematical morphology. Through analyzing the target area of image, the scope of the general gray-scale is determined. Based on the image edge and region, fast iterative algorithm is used to choose the optimum threshold as segmentation criteria. Moreover, morphology open computing is applied to the image threshold segmentation. Then the method is used in processing marine oil spill and solar flares. Different experiments of marine oil spill and solar flares based on the method show that this method can not only extract a clearer definition of interesting areas, but also can show a more clear-cut edge.

In order to improve the thermal conductivities of composites, AlN are used as thermal conductive fillers of EPDM rubber. The contact angle and surface free energy of AlN and modified AlN are studied. The influence filler amount and the surface treatment of AlN which coated by phenol formaldehyde resin (PF), on the thermal conductivities and mechanical properties of composites material are also investigated. The results show that the surface free energy of modified AlN is lower than unmodified, so the modified AlN are easier dispersion in the matrix. Through the TGA analysis, it can give a quantitative analysis of the surface coating thickness. With the increase of the filler, the thermal conductivities of composites are all on the rise, while the mechanical properties decreased in different degree. The modified AlN have active impacts on the thermal conductivities and harmful to mechanical properties of the filled EPDM rubber.

In this article, in order to improve the thermal conductivities and mechanical properties of EPDM filled with carbon nanotubes, phenol formaldehyde resin is used to coat to the surface of carbon nanotubes so as to improve the dispersion in rubber matrix and the combination with EPDM. The results show that with the ratio of CNTs and PF increased, the thermal conductivities of carbon nanotubes/EPDM composites show upward trend. Besides, with the increase of filler content, thermal conductivities of composites are improved as well. However, the mechanical properties of composites are declined. Therefore, more effective methods of modification of carbon nanotubes should be attempted, and more experiments should be conducted to improve mechanical properties of filled EPDM and ensure the high thermal conductivities at the same time.

Eight kinds of carbon black filled natural rubber composites were prepared, and thermal conductivity was studied. Acetylene black contributes much to the thermal conductivity of rubber, and tiny loading results in considerable improvement. The conductive carbon black 40B2 is advantageous for the improvement in thermal conductivity of rubber when its loading reaches middle level, and at its middle level, also tiny loading results in much improvement. Most kinds of carbon black for rubber application filled rubber composites have good properties except for N134 and N660, especially the poor contribution of N660. Additionally, in the case of carbon black filled rubber composites, addition of filler may not necessarily benefit the thermal conductivity when filler loading is not much.

Aluminum Nitride (AlN) based Surface Acoustic Wave (SAW) sensors have shown great application potentials on serving as biosensors. In this paper, we investigate the mass sensitivity of SAW sensors, which were fabricated based on Si/AlN structure by depositing aluminum oxide (AhO3) thin films on the active area between the input port and output port of the SAW devices. The material of the IDTs is aluminum. To validate the sample accommodation and protection function of the SiN thin film in bio-liquid detection processes, the contact angle of the SiN surface is also detected. We found that the mass sensitivity of the SAW devices is as high as 1958 MHz/g and the SiN surface is hydrophilic with contact angle of 45 degree. The research results indicate the AlN based SAW devices can be well employed in certain biosensing applications.

In this paper, the thermal conductivities and mechanical properties of natural rubber which is filled with graphite and modified by acrylate are studied experimentally. It is found that the thermal conductivities and mechanical properties of vulcanizates are improved significantly. The thermal conductivity and mechanical properties of graphite-filled nature rubber which is modified by the mass ratio of 5:1 between graphite and monomers are best in 3 kinds of formulations.

Rolling resistance can impact on the fuel economy and dynamics of automobile. Numerical simulation can predict the rolling resistance and reduce the experimental cost. So, a simulation model was established base on ANSYS to compute the rolling resistance. Firstly, the 3D model finite element model of a radial tire was setup to solve the strain and stress of a rolling tire. Secondly ,the temperature field of tire was analyzed in line with the analytical result of the strain and stress. Thirdly, the rolling energy loss was calculated to solve the rolling resistance. The simulation method is conducive to the structural design of tire and computation or prediction of the rolling resistance of tire.

Normal thermal conductivity of amorphous and crystalline SiO2nano-films is calculated by nonequilibrium molecular dynamics (NEMD) simulations in the temperature range from 100 to 700K and thicknesses from 2 to 6nm. The calculated temperature and thickness dependences of thermal conductivity are in good agreement with previous literatures. In the same thickness, higher thermal conductivity is obtained for crystalline SiO2nano-films. And more importantly, for amorphous SiO2nano-films, thickness can be any direction of x, y, z-axis without effect on the normal thermal conductivity, for crystalline SiO2nano-films, the different thickness directions obtain different thermal conductivity results. The different results of amorphous and crystalline SiO2nano-films simply show that film thickness and grain morphology will cause different effects on thermal conductivity.

The heat conductive silicone rubber is prepared with methy1 viny1 silicone rubber as basic gum and SiCp (SiC particle), SiCp/SiCw (SiC whisker), graphite as heat conductive fillers. The effects of filler amount, filler shape, filler size and coupling agent on the thermal conductivity of silicone rubber have been studied in this article. The result shows that when the filling amount is increasing, the thermal conductivity of composite silicone rubber will increase too. There is no evident change for thermal conductivity with the small filling fraction, while the filling amount reaches a certain value, the thermal conductivity of composite increases obviously. Moreover, the thermal conductivity added with coupling agent (KH-602) is higher than that of composite without coupling agent addition.

Carbon black has been used as the main reinforcing fillers that increase the usefulness of rubbers. In this experiment, different compounds based on natural rubber were prepared with carbon black (N330) at various loading ratios from 10 to 125 phr. The mechanical and thermal properties of rubber compounds were measured and the test data with SEM micrographs were analyzed to determine the suitable ratio of carbon black for the desired properties of rubber compound. The results showed that carbon black particles were well dispersed in compounds with loading ratios of 25-30 phr, corresponding to maximum tensile strength values. While with the increase of carbon black content, heat conductivity kept sustained increase. Fractal dimension characterized the degree of uneven dispersion of carbon black in rubber fracture surfaces. A particular value of fractal dimension was obtained to characterize the optimum mechanical property of carbon black filled natural rubber. The thermal property and fractal dimension demonstrated same variation tendency.

The geometry plays an important influence on the performance of jet reactors. Based on the fast process of acid-base neutralization, the effects of geometric parameters such as the angle of diffuser, ratio of nozzle diameter to mixing chamber diameter and the position of nozzle on mixing and reaction characteristics were analyzed using CFD in detail. The results demonstrated that: (1) an optimum ratio of nozzle diameter to mixing chamber diameter was obtained, namely 0.35. If the ratio value is larger than 0.35, the conversion rate in the jet reactor decreases, whereas if the value is smaller than 0.35, the conversion rate can not improve any more but the pressure drop increases; (2) the larger the distance between the nozzle outlet and the inlet of mixing chamber, the faster the reaction proceed is. The optimum results can be acquired when the nozzle outlet shares the same plane with the centerline of the suction inlet; (3) the smaller the angle of diffuser section, the higher conversion rate in the same cross section can be achieved and at the same time, the bigger of the pressure drop is needed.

Micro- and Macro-mixing models were built and numerical investigation of turbulent mixing in ejectors was carried out. Mixture fraction and its variance presented by Fox were remodeled to demonstrate micro- and macro-mixing performance. The length needed to reach 98% micro- and macro-mixing were founded is functions of uj/umand D/d. The mathematical scale-up models were presented based on the simulation results using least square method for micro- and macro-mixing and five different cases were used to validate the models. The results showed that macro-mixing scale-up model agreed well with CFD simulations but the micro-mixing scale-up model had a less precision compared with that of macro-mixing model. This because that the mechanism of micro-mixing process is very complexity but the CFD models we used in this work are fairy simple.

Thermal conductivity of L-J potential solid argon nano-films is calculated by equilibrium molecular dynamics (EMD) and nonequilibrium molecular dynamics (NEMD) simulations in the temperature range from 30K to 80K. A LAMMPS computer program has been modified based on classical molecular dynamics. It can be directly used to calculate the thermal conductivity of nano-films in the direction perpendicular to the film plane. Thermal conductivity calculated from this program is compared with experimental data. It is found that this computer program is competent to calculate the thermal conductivity of solid nano-films. It is also found that thermal conductivity is dependent on the simulation temperature and film thickness.

Through measuring the thermal conductivities and tensile strength of nature rubbers filled with carbon black and comparing with each other, it is shown that the difference of carbon black particle size and the structure affects on the thermal conductivity and tensile strength of nature rubber. Thermal conductivities of carbon black-filled nature rubber are enhanced with the increase of volume fraction of filler; tensile strength of composite increases first and then decreases with the increase of carbon black volume fraction.

The thermal conductivities of two rubbers filled with different carbon black (N330 and N375) are measured by experiments, and compared with five theoretical models calculated results. It is shown that thermal conductivity of carbon-filled rubber is obviously enhanced with increase of the volume filler fraction of carbon black and the thermal conductivity of carbon-filled rubber is related to the microstructure and morphology of carbon black. The estimated thermal conductivities by using the model proposed in our previous paper are of the same variation as the experimental ones of N330 carbon/rubber and N375 carbon/rubber during the range of volume fraction from 2% to 20%.

Micro- and nano- silicone carbide particles are used as heat conductive fillers of methyl vinyl silicone rubber, and the influence of filler amount, particle size and the surface treatment of filler on the thermal conductivities and mechanical properties of silicone rubber are studied. The results show that the thermal conductivities of silicone rubber are improved, but the mechanical properties are worse with the increase of the amount of fillers. The composite filled with smaller sized silicone carbide has a better thermal conductivity than that filled with large particles in a relatively high filling fraction, and composite filled with different sized silicone carbide has different mechanical properties at the same filling amount. Treatment of fillers with coupling agent (KH-560, A-171) has active impacts on the thermal conductivity but negative impacts on mechanical properties of the filled silicone rubber.

Different temperature, different frequency, different recipe, then heat generation ratio of carbon black/rubber composites will be different. An artificial neural network model has been developed based on the analysis of the relation between carbon black/rubber composites‘ heat generation ratio and temperature,frequency.The neural network model is compared with the quadratic fitting formulae and relative errors is analyzed. The simulation results indicated the neural network model’s precision is greater than the quadratic fitting formulae’s, and artificial neural network theory can be used in the research field of carbon black/rubber composites’ thermophysical properties.

Five kinds of carbon black filled natural rubber were prepared, and thermal conductivity was studied considering two factors, which include temperature and volume percent of the filler. It was found that thermal conductivity had relevance to temperature and volume percent of carbon black, besides, structure and specific area of carbon black were also very important influencing factors. Moreover, reuniting phenomenon of nanometer grade of carbon black has much effect on thermal conductivity.

The authors built up a new algorithm called FUZZY-D-P-GA which was based on the fuzzy optimization, the genetic algorithm, delicate variables’ segments thinking & parallel principle. Meanwhile, they also succeed in applying this composite method on the synthetically optimization of navigation performance and structure characteristic of ships. Through a large number of calculation, the results showed that this kind of algorithm had high efficiency and it was also reliable.

The Aluminum Nitride (AlN) thin film based surface acoustic wave sensors have been fabricated by whole CMOS compatible process. In order to study the resonant frequency behavior responses with temperature, S parameters measured by network analyzer of the AlN SAW sensors are processed with the data extraction program through MATLAB software. It is observed the extracted data of resonance frequency show linear relationship with variation of environment temperatures, which indicates we can easily carry out temperature compensation for the fabricated AlN SAW sensors. And the studied AlN based SAW sensor could also be employed as temperature sensor for further wireless sensing applications.

Based on a kind of typical high speed monohull vessel, the paper discusses an integrate optimization’s method of Synthetical Fundamental Mechanics Characteristic with the materials of some ships and some relevant experience expressions. The authors use the weighted sum of rapidity, sea-keeping ability and maneuverability as the sub-objective function of ship performances; use the weighted sum of static and dynamic properties as the sub-objective function of structural mechanics properties; The weighted sum of these 2 sub-objective functions is just the general objective function. Stability, buoyancy and some other characteristics as well as limits of design variables form the constraint conditions. The mathematic model shows that the synthetical optimization of mechanics properties for ships involves at least 49 design variables, 9 equation constraints and 5 inequality constrains. Evidently, it’s a very complicated engineering optimization. The data was gained after this algorithm(DP- genetic chaos algorithms) had applied to optimize integrate the performance of navigational performance and structure characteristic by VC++, quantities of computation results of different solving methods show that compared with other methods such as GA, chaos algorithm and their parallel algorithms, this complex algorithm can overcome GA’s premature convergence and is reliable and efficient. Above all, the software is programmed. Using this software can conveniently get the possibility distributing function of integrate optimum navigation performance of each design variables, and can provide the condition to integrate evaluation of the ship design project and the integrate decision-making of ship parameters.

In this paper, VC++ serves as a workspace to establish the features of speediness and navigation speed controlling. A mathematical model of intelligent propulsion system of an adjustable-pitch-screw-propelled hydrofoil sliding craft was built up, and then applied the fuzzy-genetic algorithm (FGA), to program the optimizing-computing process of the best combination of the controlling parameters of the system. The optimizing result indicates that FGA is capable of optimizing-computing the model quite well, Since not only all the equation restriction conditions are satisfied at a degree of more than 99.99%, but also the in equation restriction conditions are also wholly satisfied, this method is good at dealing with the restriction condition and this program can also be used to primarily optimizing-design and analyze the system.