Gas compressors are one of the most important fluid machinery in the petroleum and chemical industries. Valves and packing seals are the most critical consumable parts of the compressor. The quality and performance of the compressor determine the reliability and compression efficiency of the entire compressor unit. And maintenance cycle. Polymer-based composites have good self-lubricating ability, excellent wear resistance and strong corrosion resistance, so the application of high polymer parts in compressors has received more and more attention. However, due to the influence of frictional temperature rise, the strength and wear resistance of such components tend to decrease, which affects their performance and life. For this reason, research and prediction of friction temperature rise of high polymer components and its influencing factors are developed. Differently formulated composite friction components, improved component reliability and extended service life have important practical significance.

In view of the above research purposes, the pin-disk friction pair commonly used in the field of tribology is used as a research object to analyze the influence of material properties and working conditions on the temperature rise of composite friction components. Researchers at home and abroad have conducted an analysis of the temperature rise of the pin-disk friction pair composed of single-phase materials. Kar et al. and Yevtushenko et al. studied the analytic formula of the frictional heat flow distribution coefficient of the one-dimensional temperature distribution of the metal material pin, but did not consider the convective heat transfer effect of the disk. The steady-state and non-steady-state analysis of the temperature field of the plastic pin was carried out, but the calculation method of the frictional heat flow distribution coefficient and the influence of the composite composition were not studied. Based on a new calculation method of convective heat transfer coefficient and the above-mentioned related calculation methods, this paper analyzes the friction temperature rise of polymer pin, and studies the variation of temperature field predicted by different heat conduction models when the pin is subjected to temperature abrupt change.

In order to make the problem easier to handle without losing its practical significance, the following assumptions are made: (1) The entire friction end face of the pin is uniformly in contact with the disk circumference.

(2) In the contact area of ​​the pin plate, the frictional heat flow is uniform and is conducted in a single direction, that is, only in the pin axis direction.

(3) The material is uniform and dense, and the thermal conductivity is equal everywhere.

(4) Compared with the overall frictional heat, the heat taken away by the grinding debris is small and negligible.

(5) The temperature of the pin end face away from the contact area is room temperature.

(6) The friction surface does not undergo a phase change.

The prediction of the temperature rise of the end face is more accurate than the numerical method, and the location away from the friction interface is deviated from the experimental value due to the limitation of the thermal boundary condition.

The parabolic heat conduction model sets the pin-disk friction interface temperature to Tw and introduces the dimensionless parameter θ=(T-T2, which gives the dimensionless form of the one-dimensional unsteady parabolic heat conduction model of the pin as follows. This is a parabolic type. For partial differential equations, the implicit difference scheme is unconditionally stable, and a stable and reliable solution can always be obtained. The pin is axially equated and solved by Gauss-Seidal iteration method, where the boundary condition is: for i=10 From the above formula, the relationship between them can be obtained as follows: Under the parabolic heat conduction control model, the boundary temperature disturbance propagates to the inside of the material in pure diffusion form, and the temperature rise of the middle part of the material at the beginning is small; When the boundary temperature changes, the temperature at each internal point also begins to change, and when the time is long enough, the internal temperature of the material reaches equilibrium.

The hyperbolic heat conduction model is given by the hyperbolic heat conduction model as follows: Similarly, using implicit differential formatting as the difference format, the full implicit equation of the hyperbolic heat conduction model is: the Gauss-Seidal iteration method is still used in the solution method. (Boundary conditions are the same as parabolic models). The calculation results are shown in Figure 3.

It can be seen from Fig. 3 that since the hyperbolic heat conduction model is a wave equation, the variation law of the internal temperature of the material is very different from the Fourier heat conduction equation in this model: when there is a temperature disturbance on the boundary of the material. The temperature disturbance is gradually transmitted from the boundary to the inside of the material in the form of attenuated temperature fluctuations, but for the high polymer, since it has the same short relaxation time as the metal material, the heat capacity is smaller than that of the biological material and the porous material. A lot, so the temperature disturbance is very slow.

The hyperbolic heat conduction model and the parabolic heat conduction model have the same prediction effect on the frictional temperature rise or temperature field of the moving parts of the polymer, although the temperature changes at the beginning of the different models are completely different, but the time is large enough. The model will get the same result, that is, to achieve temperature balance.

Conclusion (1) The one-dimensional steady-state temperature field of high polymer composite parts for compressors is solved analytically and numerically. The new heat flow distribution coefficient calculation method is given. The calculation results are in good agreement with the experimental data. Sex.

(2) Comparing the influence of hyperbolic heat conduction model and conventional parabolic heat conduction model on the unsteady temperature field of high polymer friction components, it is considered that when the components are subjected to temperature abrupt or high heat flow, the latter can accurately predict. Meet the actual requirements of the project.

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