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Based on the actual service condition of highway pavement colored thin anti-skidding layers, with materials of color quartz sand and two-component acrylic resin as basis, we designed such tests as the bond strength, shearing strength, tear strength, fatigue performance and aggregate polished value, and included the freeze-thaw cycle and de-icing salt and other factors in the experiment, connecting with the climate characteristics of circumpolar latitude and low altitude in Heilongjiang province. Through the pavement performance test, it is confirmed that the colored thin anti-skidding layers can adapt to cold and humid climate conditions, and its physical mechanical properties are good.Based on the actual service condition of highway pavement colored thin anti-skidding layers, with materials of color quartz sand and two-component acrylic resin as basis, we designed such tests as the bond strength, shearing strength, tear strength, fatigue performance and aggregate polished value, and included the freeze-thaw cycle and de-icing salt and other factors in the experiment, connecting with the climate characteristics of circumpolar latitude and low altitude in Heilongjiang province. Through the pavement performance test, it is confirmed that the colored thin anti-skidding layers can adapt to cold and humid climate conditions, and its physical mechanical properties are good.

Experiments and theoretical analysis of an Organic Rankine Cycle (ORC) system with variable and invariable nozzles were carried out in this paper. Both of the pressures at throat and nozzle outlet were measured. Results showed the experimental value matched well with the theoretical calculation value. Differences between invariable nozzle ORC system and variable nozzle ORC system are compared. The unique cycle performances were revealed and analyzed, including mass flowrate, heat absorption ability, output work, and thermal efficiency. The mass flowrate, the inlet temperature and pressure can be adjusted independently in a variable nozzle ORC system, but these results cannot be obtained in an invariable nozzle ORC system. The way to optimize the invariable nozzle ORC system was discussed, and the principles of design a system equipped with an invariable nozzle were recommended.

A BGK-type model is a simplified model to the Boltzmann equation where the complicated collision integral is approximated using a simple relaxation term. In this paper, a generalized BGK-type model is proposed by combining the original BGK, Shakhov and ellipsoidal statistical models. To verify the new model, theoretical and numerical analysis is performed. The Chapman-Enskog expansion shows that the generalized model can recover the Navier-Stokes-Fourier and Burnett equations by choosing properly the introduced parameters. In addition, the collision term of the model is evaluated for several designed relaxation problems. Results show that the new model can match the results of third-order moments obtained with DSMC method by adjusting the free parameters.

In this paper, a new approach is presented for numerical evaluation of three‐dimensional (3D) weakly, strongly, hyper‐ and super‐singular boundary integrals which exist in the Cauchy principal value sense. In the approach, the singularities involved in integration kernels are analytically removed based on the use of the radial integration method and expansions of the non‐singular parts of the kernels as power series with respect to the local distance in the intrinsic coordinate system. One of the features of the approach is that the global distance between source and field points is exactly expanded as the power series in local one for linear and high order boundary elements. This expansion is different from existing approaches in which the Taylor series is used to approximate the distance and other quantities. Some examples are provided to verify the correctness and efficiency of the presented approach.