The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform
Xudong Peng - One of the best experts on this subject based on the ideXlab platform.
-
A comprehensive multi-objective, multi-parameter and multi-condition optimization of a Spiral Groove in dry gas seals
2020Co-Authors: Jinbo Jiang, Wenjing Zhao, Jie Jin, Xudong PengAbstract:Abstract Dry gas seals are widely used in rotating equipment for fluid leakage control and operating efficiency enhancement. Multi-dimensional optimization of geometric parameters of the Spiral Groove was conducted with considering the comprehensive effect of working conditions, objective functions and the other geometric parameters. Different optimization methods were proposed for solving the multi-dimensional optimization problems. The optimal values of Groove width ratio, Groove length ratio and Spiral angle for the excellent steady performance of Spiral Grooves under different working conditions were obtained by employing a genetic algorithm and loop iteration optimization method. The performance comparison of two dry gas seals with different geometric parameters was conducted experimentally to verify the effectiveness of numerical results. The results showed that optimal geometric parameters of the Spiral Groove were significantly influenced by working conditions, objective function and the other geometric parameters. Maximum film stiffness and stiffness-leakage ratio of the Spiral Groove dry gas seal obtained by genetic algorithm enhanced up to 30% and 45% larger than those obtained by the conventional single factor optimization. The film stiffness and stiffness-leakage ratio were more sensitive to geometric parameters of a Spiral Groove than that of opening force. The optimization results obtained in this paper provide a theoretical and experimental reference for the design of dry gas seals in different working conditions to meet various sealing performance requirements.
-
experimental and theoretical studies of the dynamic behavior of a Spiral Groove dry gas seal at high speeds
Tribology International, 2018Co-Authors: Yua Che, Jinbo Jiang, Xudong Peng, Xiangkai MengAbstract:Abstract Because of great axial vibration of the rotor system, dry gas seal has a big film thickness disturbance, which may cause contact rubbing of seal faces or excessive leakage. Focusing on this problem, experimental studies on transient-state film thickness and leakage rate of a Spiral Groove dry gas seal at high-speeds are carried out under different spring pressures and different Spiral Groove depths. And the experimental results of film thickness disturbance and average leakage rate are predicted by perturbation method and gas lubrication theory. Results show that the theoretical results of variation trends of film thickness disturbance amplitudes coincide well with the experimental data, and it also represents that the perturbation method is an effective forecasting method in dynamic analysis.
-
Leakage and Stiffness Characteristics of Bionic Cluster Spiral Groove Dry Gas Seal
Chinese Journal of Mechanical Engineering, 2018Co-Authors: Jinbo Jiang, Xudong Peng, Yua CheAbstract:Spiral Groove dry gas seal (S-DGS), the most widely used DGS in the world, encounters the problem of high leakage rate and inferior film stability when used in high-speed machinery equipment, which could not be well solved by optimization of geometrical parameters and molded line of Spiral Groove. A new type of bionic cluster Spiral Groove DGS (CS-DGS) is proved to have superior film stability than S-DGS at the condition of high-speed and low-pressure numerically. A bionic CS-DGS is experimentally investigated and compared with common S-DGS in order to provide evidence for theoretical study. The film thickness and leakage rate of both bionic Spiral Groove and common Spiral Groove DGS are measured and compared with each other and with theoretical values under different closing force at the condition of static pressure, high-speed and low-pressure, and the film stiffness and stiffness-leakage ratio of these two face seals are derived by the relationship between closing force and film thickness at the steady state. Experimental results agree well with the theory that the leakage and stiffness of bionic CS-DGS are superior to that of common S-DGS under the condition of high-speed and low-pressure, with the decreasing amplitude of 20% to 40% and the growth amplitude of 20%, respectively. The opening performance and stiffness characteristics of bionic CS-DGS are inferior to that of common S-DGS when rotation speed equals to 0 r/min. The proposed research provides a new method to measure the axis film stiffness of DGS, and validates the superior performance of bionic CS-DGS at the condition of high-speed and low-pressure experimentally.
-
Thermo-hydrodynamic characteristics of Spiral Groove gas face seals operating at low pressure
Tribology International, 2016Co-Authors: Shaoxian Bai, Xudong PengAbstract:Abstract Thermo-hydrodynamic behaviors of Spiral Groove gas face seals are investigated for the cases of low seal pressure. Pressure and temperature fields of gas film are calculated, and then influence of thermal distortion on seal performance are analyzed. It is found that Spiral Grooves lead to complex film temperature distributions and rotational speed results in the increase of whole film temperature. But the shear heat and pumping effect of Spiral Grooves have little influence on film temperature gradient along the leakage direction. The face thermal distortion, forming divergent clearance along the leakage direction, makes the opening force decrease and the leakage increase. A higher seal pressure and clearance will result in a larger thermal distortion. And the rotational speed may enhance the face thermal distortion further in some low pressure cases.
-
thermoelastohydrodynamic behavior of gas Spiral Groove face seals operating at high pressure and speed
Journal of Tribology-transactions of The Asme, 2015Co-Authors: Shaoxian Bai, Xudong Peng, Shizhu WenAbstract:A numerical modeling of thermoelastohydrodynamic gas Spiral Groove face seal behavior is presented. Temperature fields of the fluid film and the seal rings are computed, as they are the elastic and thermal distortions of the rings. Numerical analysis is carried out on a gas Spiral Groove face seal taking into account of choked flow effect. Analysis results show that both elastic and thermal distortions induce strong influence on the geometry of the fluid film, forming obvious divergent clearance which leads to significant decrease of minimum equilibrium clearance, exceeding 50% in degree. Thermal distortion may induce the same influence degree as elastic distortion on the minimum equilibrium clearance in high pressure cases, but the rotation speed has no obvious influence on the minimum clearance when both elastic and thermal distortions are considered. The thermal distortion as well as elastic distortion should be concerned in high pressure analysis.
Michael M. Khonsari - One of the best experts on this subject based on the ideXlab platform.
-
Thermohydrodynamic Analysis of Spiral Groove Mechanical Face Seal for Liquid Applications
Journal of Tribology, 2012Co-Authors: Yifan Qiu, Michael M. KhonsariAbstract:In this study, a three-dimensional thermohydrodynamic (THD) CFD model is developed to study the characteristics of an inward pumping Spiral Groove mechanical seal pair using a commercial CFD software CFD-ACE + . The model is capable of predicting the temperature distribution and pressure distribution of the seal pair. Based on the CFD model, a parametric study is conducted to evaluate the performance of the seal. It is found that thermal behavior plays an important role in the overall performance of a seal. The Spiral Groove parameter can be optimized to achieve desired performance. The optimization is dependent on the application requirement of the seal.
-
Investigation of tribological behaviors of annular rings with Spiral Groove
Tribology International, 2011Co-Authors: Y. Qiu, Michael M. KhonsariAbstract:Abstract A series of experiments is conducted to study the tribological behavior of Spiral Groove thrust bearings. The experimental system consists of a nominally flat upper ring mating with a stationary Spiral Groove lower ring in fully flooded lubrication environment. Spiral Groove thrust bearings with different Spiral angles subjected to different loads and speeds are tested. Stribeck-like curves are obtained and their characteristics are discussed. Transition points from mixed to hydrodynamic lubrication are experimentally established. In addition, a theoretical model is developed to gain further insight into the frictional characteristics of Spiral Grooves in both the hydrodynamic regime and the mixed lubrication regime.
Yunlei Wang - One of the best experts on this subject based on the ideXlab platform.
-
dynamic response of Spiral Groove liquid film seal to impact conditions
Tribology International, 2020Co-Authors: Muming Hao, Xinhui Sun, Yunlei Wang, Hengchao CaoAbstract:Abstract The dynamic response of the Spiral Groove liquid film seal to three types of impact are studied by developing a three-DOF dynamic model which takes average flow model, cavitation effect, squeeze effect and face contact into account. A Gaussian pulse function is first applied to simulate the impact to the seal. Results indicate that the seal can maintain hydrodynamic lubrication regime to avoid significant face contact regardless of the impact type. The pressure variation impact does not necessarily induce leakage due to the dramatically narrowed sealing gap. The shaft drifting and bending impact conditions can bring about leakage risk, but the symptomatic flow rate induced by the former is much heavier than that by the latter at the representive moment.
-
experimental study of cavitation characteristic of single row reverse Spiral Groove liquid film seals
Tribology International, 2020Co-Authors: Muming Hao, Xinhui Sun, Chaohe Yang, Yunlei WangAbstract:Abstract A series of experiments is conducted to study the cavitation in the single-row reverse Spiral Groove liquid-film seals. The experimental system withstanding internal pressure consists of a transparent rotating ring mating with a stationary ring textured with Grooves. Liquid-film seals with different Groove parameters under different operating conditions are tested, acquiring the distribution and evolution of cavitation and fitting the experimental relations of cavitation boundaries. Results indicate that cavitation occurs in the Grooves and many protruding bubbles appear near the liquid-film reformation boundary. Increasing pressure effectively reduces the cavitation but for speed, it's opposite. Although the increase of Groove depth and the decrease of Spiral angle reduces the cavitation area, effects of them on the cavitation boundaries are different.
Muming Hao - One of the best experts on this subject based on the ideXlab platform.
-
dynamic response of Spiral Groove liquid film seal to impact conditions
Tribology International, 2020Co-Authors: Muming Hao, Xinhui Sun, Yunlei Wang, Hengchao CaoAbstract:Abstract The dynamic response of the Spiral Groove liquid film seal to three types of impact are studied by developing a three-DOF dynamic model which takes average flow model, cavitation effect, squeeze effect and face contact into account. A Gaussian pulse function is first applied to simulate the impact to the seal. Results indicate that the seal can maintain hydrodynamic lubrication regime to avoid significant face contact regardless of the impact type. The pressure variation impact does not necessarily induce leakage due to the dramatically narrowed sealing gap. The shaft drifting and bending impact conditions can bring about leakage risk, but the symptomatic flow rate induced by the former is much heavier than that by the latter at the representive moment.
-
experimental study of cavitation characteristic of single row reverse Spiral Groove liquid film seals
Tribology International, 2020Co-Authors: Muming Hao, Xinhui Sun, Chaohe Yang, Yunlei WangAbstract:Abstract A series of experiments is conducted to study the cavitation in the single-row reverse Spiral Groove liquid-film seals. The experimental system withstanding internal pressure consists of a transparent rotating ring mating with a stationary ring textured with Grooves. Liquid-film seals with different Groove parameters under different operating conditions are tested, acquiring the distribution and evolution of cavitation and fitting the experimental relations of cavitation boundaries. Results indicate that cavitation occurs in the Grooves and many protruding bubbles appear near the liquid-film reformation boundary. Increasing pressure effectively reduces the cavitation but for speed, it's opposite. Although the increase of Groove depth and the decrease of Spiral angle reduces the cavitation area, effects of them on the cavitation boundaries are different.
Xiang Liu - One of the best experts on this subject based on the ideXlab platform.
-
thermohydrodynamic analysis of high speed water lubricated Spiral Groove thrust bearing considering effects of cavitation inertia and turbulence
Tribology International, 2018Co-Authors: Xiaohui Lin, Shuyun Jiang, Chibin Zhang, Xiang LiuAbstract:Abstract A thermohydrodynamic cavitating flow lubrication model including effects of cavitation, inertia and turbulence for high speed water-lubricated Spiral Groove thrust bearing was established. The static characteristics of the water-lubricated Spiral Groove thrust bearing at high speed condition were investigated using this model. The numerical calculation results have shown that load carrying capacity and friction torque reduce due to inertia and cavitation in high speed condition, while that load carrying capacity and friction torque increase due to turbulence. The maximum temperature rise increases due to inertia effect, and reduces due to cavitation effect. In addition, the influence of inertia effect on the static characteristics of water-lubricated Spiral Groove thrust bearing was greater than the cavitation effect under high speed condition.