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In this paper, a homogenization‐based multi‐scale method for predicting the effective thermal conductivity of porous materials with radiation is presented, which considers the effect of geometry and distribution of pores. Using homogenization method to solve the pure conductive problem of porous materials with periodic structure, the effective thermal conductivity without considering radiation is predicted, and a temperature field in a local domain of a unit cell is obtained. This temperature field is taken as the good approximation of the real temperature distribution, and the radiative thermal conductivity is obtained. The effect of the microstructure, the distribution and geometry of pores on heat transfer of porous materials is discussed. It is concluded that the dimension of the pores is an important influence factor on the thermal transfer property of porous materials if radiation is considered. Increasing the pore’s dimension enhances the contribution of radiation to the heat transfer property of porous materials. For porous materials with cylindrical and spherical pores, the radiative thermal conductivity is proportional to pore’s diameter.

This study aims to analyze the roller dynamic characteristics and cage whirling of tapered roller bearing considering roller tilt and skew which provide a theoretical basis for the design and application of tapered roller bearing.

Based on rolling bearing dynamic analysis, the dynamic differential equations of tapered roller bearing are established. Fine integral method and predict correct Adams–Bashforth–Moulton multi-step method are used to solve the dynamic differential equations of tapered roller bearings.

Friction at the flange contact between roller and large flange is the chief factor of roller skew. In comparison to cone speed, axial loads have more visible effect on roller skew, and proper speed or axial load is beneficial to sustain cage motion and decrease cage instability. Under the combined effort of axial load and radial load, the distribution of roller skew is correlated to the roller-flange contact load. In addition, roller skew angle in loaded zone is larger than that in unloaded zone; hence, it is helpful for cage stability if an extent radial load is applied. The pocket clearance of cage has very small influence on roller skew; therefore, a reasonable pocket clearance is suggested to assure minimum instability of cage. Friction coefficient of flange contact has a large effect on roller skew, and cage whirl is found to demonstrate a circular orbit with increasing friction coefficient.

The dynamic differential equations of tapered roller bearing considering roller large end/inner ring back face rib contact under various lubrication states were established. The impact of flange friction working conditions and cage pocket clearance on cage instability and roller skew were focused on. It is the first time that the ratio of the standard deviation of the cage-center translational speed to its mean value is used to access the instability of cage in tapered roller bearing.

The purpose of this paper is to study the influence of the cage dynamic unbalance on the dynamic performances in cylindrical roller bearings.

The dynamic analysis model which considering cage dynamic unbalance is presented, and the relationship between the cage dynamic unbalance and the cage stability, the cage slip ratio and the cage skew angle is investigated.

Cage dynamic unbalance has a great effect on the cage stability. The cage dynamic unbalance which in an axial excursion affects the cage characteristics is greater than that only in the radial direction. The cage slip ratio and the cage skew increases with the cage dynamic unbalance, especially with the axial excursion. The non-metal cage is more sensitive to the cage dynamic unbalance than that of the metal cage.

The analytical method and model can be applied by the bearing engineering designers.

The purpose of this study is to investigate the effect of roller dynamic unbalance on cage stress.

Considering the impact of roller dynamic unbalance, the dynamic analysis model of high-speed cylindrical roller bearing is established. And then the results of dynamic model are used as the boundary conditions for the finite element analysis model of roller and cage to obtain the cage stress.

Roller dynamic unbalance affects the contact status between roller and cage pocket and causes the overall increase in cage stress. The most significant impact on cage stress is roller dynamic unbalance in angular direction of roller axis, followed by radial and axial directions. Smaller radial clearance of bearing and a reasonable range of pocket clearance are beneficial to reduce the impact of roller dynamic unbalance on cage stress; the larger cage guide clearance is a disadvantage to decrease cage stress. The impact of roller dynamic unbalance on cage stress under high-speed condition is greater than that in low-speed conditions.

The research can provide some theoretical guidance for the design and manufacture of bearing in high-speed cylindrical roller bearing.

The cure simulation of composite structures with arbitrary geometry can be investigated by the finite element program.

Finite element method is employed in this work.

The simulated results match the experimental results well, which demonstrates the finite element analysis models are reliable. Compared with the one- and two-dimensional finite element analysis, temperature and degree of cure can be calculated at any point within composite structures in the present simulation analysis. The cure simulation of composite structures with arbitrary geometry can be investigated by the finite element program.

A coupled thermokinetic simulation of the liquid composite molding process based on a three-dimensional finite element method is presented. The cure simulation of composite structures with arbitrary geometry can be investigated by the finite element program.

The purpose of this paper is to establish a dynamic analysis model of composite cylindrical roller bearings, investigate the effects of different working conditions on the kinematic characteristics of composite bearings and compare the differences between them and solid roller bearings.

This paper establishes a dynamic analysis model for composite cylindrical roller bearings and proves the correctness of the established model by establishing dynamic vibration experiments and contact theory for composite roller bearings. Comparative analysis was conducted on the effects of coupling changes in rotational speed, load, number of rollers and filling ratio on parameters such as bearing static stiffness, contact stress and vibration acceleration.

The composite roller can enhance the bearing’s operational stability and minimize contact stress, but that a higher filling ratio is going to increase the bearing’s stiffness. The acceleration degree of bearing vibration, the load on the outer raceway nodes and the bearing stability all decrease as inner ring speed rises.

A dynamic calculation model of composite cylindrical roller bearings is established, and the influence of multiparameter coupling changes on bearing vibration and contact is studied, which lays a foundation for the structural improvement of the bearings.

The purpose of this paper is to present a finite element analysis (FEA) of filament-wound composites, as well as application of these materials.

In this paper, a new finite element method of filament-wound composite is presented. The stress and strain fields in the composite cylinders are analyzed using the ABAQUS software packages for considering the filament undulation and crossover. The paper presented results of buckling load of composite cylinders with different types of filament-winding patterns.

The result of the example shows that the stress distributions are uniform along the cylinder length and around the circumference when the analytical approach is based on the conventional FEA. The stress distributions are not uniform along the cylinder length and around the circumference for considering the filament undulation and crossover. The stress units are arranged in a regular geometric pattern around circumference and along the axis of rotation. The analysis of the effect of filament-winding mosaic patterns on the mechanical characteristics of composite cylindrical is presented in the paper.

The stress and strain fields in the composite cylinders were analyzed for considering the filament undulation and crossover. The buckling load of composite cylinders with different types of filament-winding patterns was presented in this paper.

In order not to affect the highway and railway traffic under the bridge during the construction process, bridges adopting swivel construction method are increasingly used at areas where the traffic is heavy. Previous studies are mostly conducted by assuming that the bridge is under its own stability conditions, without considering the impact of construction error, changes of external condition and wind-induced vibration on the stability of the bridge, which poses serious challenges to the bridge construction process. This paper aims to analyze the extent to which static load and fluctuating wind effect influence structural stability and to test the credibility of the structure.

A finite element calculation method is used to analyze a T-shaped rigid frame swivel bridge. A full bridge model was built, and a local model of the turntable structure established; the two are then combined means of node coupling. Subsequently, the three sensitivity indexes – deflection rate, stress change rate and the change rate of spherical hinges – are used to evaluate in what way the bridge stability is influenced under various factors.

It is found that the stability of the swivel bridge is quite sensitive to unilateral overweight, steel beam tension and wind-induced vibration effects but less sensitive to the change of bulk density. Also found is that the change of elastic modulus exerts some effects on deflection but has negligible effects on other stability indexes. Furthermore, the transverse unbalanced torque on the bridge generated by wind-induced vibration is an important factor in determining the size of the turntable, indicating that it is not just controlled by the weight of the bridge.

All factors affecting the stability of swivel construction are analyzed, and solutions to reduce the influence are proposed. The influence of wind-induced vibration effects on swivel construction is analyzed for the first time. It is pointed out that wind-induced vibration effects have great influence on the structure, and its influence could not be neglected.

Swivel construction is a new bridge construction method, which can minimize the impact on railway and highway traffic. Previous studies were based on single factor and static analysis, which cannot reflect the real state of structures. The purpose of this paper is to establish a dynamic model of the structure and to analyze the situation under multi-variable coupling effects to accurately simulate the real state of the structure.

Finite element software ANSYS was used to establish dynamic model of turntable structure and then to analyze the effects of multiple factors on total stress, friction stress and slipping distance of the turntable structure.

It is concluded that the unbalanced weight and radius of spherical hinges have great influence on the turntable structure, so the design should be strictly considered. Friction stress and angular acceleration have little effect on the turntable structure.

This paper provides simulation of the whole process of swivel construction method. Whereas previous studies focused on static analysis, this paper focuses on the dynamic analysis of swivel construction method. The mechanics of the swivel structure under multiple factors was analyzed. According to the analysis results, the design parameters of the turntable structure are optimized.

The purpose of this article is to put forward China’s Hanyu Pinyin word guanli as an academic basic term to the world.

GUANLI as an academic basic term, which holds multiple meanings of several English words, such as management, administration, governance, etc. As a basic term, GUANLI, derived several words, such as GUANLIOLOGY, GUANLIST/GUANLIER and GUANLIWORK/GUANLIJOB, to precisely and exactly convey the Chinese GUANLI ideas. It is the historical mission and opportunity for the authors to research and establish the Chinese School of Modern GUANLI Science (CSMGS).

It is inevitably necessary to build the combined Chinese–Western discourse system of GUANLI science (CCWDSGS). Some other research results of CSMGS are also presented in this paper.

It is needless to say that there are still lots of problems in China, including in the GUANLI field. These problems will gradually be solved in China’s reform and development that takes place continuously. New problems will come up while old problems are being solved and settled; problems producing in a loop, problems solving in a loop, this is the dialectics. The authors have full confidence in solving problems, as well as in China’s development and future.

Practice comes first and then it is followed by theory. The authors first have the “China Model”, followed by the “Chinese School” consequently. The “China Model” has already been there, and the “Chinese School” relies on the author’s proactive research and innovation. It is just the right time for the authors to study and create the CSMGS. This is the historical mission and opportunity awaited by contemporary Chinese.