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Article
Publication date: 9 April 2018

Haibin Chen, Jie Zhu, Fangwei Xie, Xinjian Guo and Xudong Zheng

The purpose of this paper is to use the viscosity of fluid to transmit power known as the hydro-viscous drive (HVD) to research the effect of two-phase flow on transmission…

68

Abstract

Purpose

The purpose of this paper is to use the viscosity of fluid to transmit power known as the hydro-viscous drive (HVD) to research the effect of two-phase flow on transmission characteristics.

Design/methodology/approach

In this paper, a 3D computational model of oil film between friction pair was built to study the transmission characteristics of a two-phase oil film, and the distribution contours of pressure and temperature of oil film were investigated using the computational fluid dynamics technology.

Findings

The finding of the paper suggests that the distribution law of pressure and temperature of two-phase oil film is almost linear along the radial direction. However, since the physical phenomena near the outlet of the oil film are entirely different, there exists fluctuation. Meanwhile, the volume fraction of air was obtained at different rotation speeds, and the maximum value is 10.55 percent. Compared to the single-phase oil film, the torque transferred by the oil film is not linear with the rotation speed, its value decreases gradually.

Originality/value

This paper’s conclusions are very important for the study of HVD and its applications, which provide a new idea to further study the mechanism of oil film transmission and its cavitation. The development of fluid viscous speed clutch is dedicated to a large industrial fan and water pump speed regulation and energy saving. With the successful application of the technology, it will have more wide applications in different fields, such as, in steel, water, petrochemical, power plant of slag pump and exhaust fan.

Details

International Journal of Structural Integrity, vol. 9 no. 2
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 26 September 2019

Zhibao Li, Fangwei Xie, Junyu Sun, Jie Zhu, Xudong Zheng, Xinjian Guo, Yun Wang and Yinqun Hua

The purpose of this paper is to study the temperature characteristics of hydro-viscous clutch with different structure of friction disks and obtain the distribution of film…

133

Abstract

Purpose

The purpose of this paper is to study the temperature characteristics of hydro-viscous clutch with different structure of friction disks and obtain the distribution of film temperature.

Design/methodology/approach

The mathematical model of oil film between friction disks with radial grooves is established. Based on the flow rate equation, the temperature rise equation of oil film is deduced. Considering two-phase flow, the temperature distribution in the oil shear stage and the effects of the ratio of inner radius to outer radius on film temperature rise is studied by using computational fluid dynamics (CFD) technology.

Findings

The results show that when input speed is constant, the increase in the ratio of inner to outer radius leads to an increase in the peak temperature and the decrease in the ratio results in a larger increasing rate of temperature.

Originality/value

These results are of interest for the study of hydro-viscous drive and its applications. This study can also provide a theoretical basis for the mechanism of temperature rise by considering the effect of two-phase flow.

Details

Industrial Lubrication and Tribology, vol. 72 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 22 July 2019

Qi Sun, Fangwei Xie, Kuaidi Wan, Xinjian Guo, Jie Zhu, Van Xo Nguyen and Yun Wang

The purpose of this paper is to study the influences of the oil film thickness between the friction pairs, the rotational speed of the active and passive friction disks and the…

103

Abstract

Purpose

The purpose of this paper is to study the influences of the oil film thickness between the friction pairs, the rotational speed of the active and passive friction disks and the inlet pressure of the lubricant on the transmission efficiency.

Design/methodology/approach

A mathematical model of transmission efficiency was established, and the efficiency of transmission was studied by means of numerical analysis.

Findings

The results demonstrate that the transmission efficiency decreases with the thickness of the oil film increases. When the thickness of oil film d = 0.1 mm, the relationship between transmission efficiency and transmission ratio is linear, that is, with the transmission ratio increases, the transmission efficiency also increases which does not change with the inlet pressure changes. However, when d = 0.1 mm, their relationship is non-linear; the efficiency increases first and then decreases as the transmission ratio increases, but decreases as the inlet pressure increases.

Originality/value

The authors obtained a rule is that increasing the rotational speed and reducing the inlet pressure of the lubricating oil can improve the transmission efficiency. This study can provide a theoretical basis for power transmission designing of hydro-viscous clutch.

Details

Industrial Lubrication and Tribology, vol. 71 no. 7
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 9 April 2018

Fangwei Xie, Jie Zhu, Jianzhong Cui, Xudong Zheng, Xinjian Guo, Yun Wang and Ramesh K. Agarwal

The purpose of this paper is to study the dynamic transmission of the oil film in soft start process of hydro-viscous drive (HVD) between the friction pairs with consideration of…

152

Abstract

Purpose

The purpose of this paper is to study the dynamic transmission of the oil film in soft start process of hydro-viscous drive (HVD) between the friction pairs with consideration of surface roughness, and obtain the distribution law of temperature, velocity, pressure, shear stress and viscous torque of the oil film.

Design/methodology/approach

The revised soft-start models of HVD were derived and calculated, including average Reynolds equation, asperity contact model, load force model and total torque model. Meanwhile, a 2D model of the oil film between friction pair was built and solved numerically using computational fluid dynamics (CFD) technique in FLUENT.

Findings

The results show that the maximum temperature gradually reduces from the intermediate range (z = 0.5 h) to the inner side of the friction pair along the direction of oil film thickness. As the soft-start process continues, pressure gradient along the direction of the oil film thickness gradually changes to zero. In addition, tangential velocity increases and yet radial velocity decreases with the increase of the radius.

Originality/value

In this paper, it was found that the viscous torque calculated by the numerical method is smaller than that by the CFD model, but their overall trend is almost the same. This also demonstrates the effectiveness of the numerical simulation.

Details

Industrial Lubrication and Tribology, vol. 70 no. 3
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 October 2018

Fangwei Xie, Xinjian Guo, Diancheng Wu, Bing Zhang, Xudong Zheng, Dengshuai Wang and Yun Wang

In this paper, a kind of an oil groove structure which could improve the transmission torque of an oil film was designed, i.e. the width and depth of oil groove gradually decrease…

80

Abstract

Purpose

In this paper, a kind of an oil groove structure which could improve the transmission torque of an oil film was designed, i.e. the width and depth of oil groove gradually decrease with the increase in the radius.

Design/methodology/approach

Effects of the structural parameters of the oil groove on the hydro-viscous drive (HVD) characteristics with variable rotational speed were investigated by means of numerical calculation.

Findings

Research results show that with the decrease of the width and depth of the oil groove at the outer diameter, transmission torque increases, while the temperature is almost unchanged. Keeping the effective area unchanged, comparing the transmitted torque under the oil groove angle θ2 = 0.5° and θ2 = 4.5°, the former was almost 200 per cent of the latter; the torque transmitted with h2 = 0.05 mm was almost 150 per cent of that with h2 = 0.2 mm.

Originality/value

In this paper, the authors analyze the friction surface of the friction plate between the oil groove, oil distribution and oil film transfer torque from the oil groove structure parameters and found methods to improve the transmission torque. For the first time, the influence of the structural parameters of oil groove on the characteristics of HVD was studied under the condition of variable rotational speed, and a better method to improve the transmission torque was proposed.

Details

Industrial Lubrication and Tribology, vol. 70 no. 9
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 17 August 2018

Fangwei Xie, Xudong Zheng, Yaowen Tong, Bing Zhang, Xinjian Guo, Dengshuai Wang and Yun Wang

The purpose of this paper is to study the working characteristics of hydro-viscous clutch at high rotational speeds and obtain the trend of flow field variation of oil film.

125

Abstract

Purpose

The purpose of this paper is to study the working characteristics of hydro-viscous clutch at high rotational speeds and obtain the trend of flow field variation of oil film.

Design/methodology/approach

The FLUENT simulation model of the oil film between the friction disks is built. The effect of variation of working parameters such as input rotational speed, oil flow rate and film thickness on two-phase flow regime and transmission torque is studied by using the volume of fluid model.

Findings

The results show that the higher the rotational speed, the severer the cavitation is. In addition, the two-phase flow region makes the coverage of oil film over the friction pairs’ surface reduce, which results in a decrease in transmission torque for the hydro-viscous clutch.

Originality/value

These simulation results are of interest for the study of hydro-viscous drive and its applications. This study can also provide a theoretical basis for power transmission mechanism of oil film by considering the existence of a two-phase flow regime consisting of oil and air.

Details

Industrial Lubrication and Tribology, vol. 70 no. 8
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 5 February 2018

Kaiyu Dai, Fangwei Xie, Qingsong Gao, Desheng Zhang, Erming Ding and Xinjian Guo

The purpose of this paper is to study the pressure response characteristics of the cartridge electromagnetic relief valve, which offers the problems caused by low pressure…

116

Abstract

Purpose

The purpose of this paper is to study the pressure response characteristics of the cartridge electromagnetic relief valve, which offers the problems caused by low pressure response and low efficiency in hydraulic plate shearing machines.

Design/methodology/approach

First of all the mathematical model of the cartridge electromagnetic relief valve is deduced to analyze the influence of the relevant parameters on the system pressure response. Then experiments are conducted to research the dynamic characteristics on building and relieving pressure. Through comparison of theoretical and experimental research, the results are found.

Findings

The results show that the input flow, working pressure, diameter of adjacent damping hole, and spring stiffness of the main valve have great influence on building pressure of the system, and have no influence on relieving pressure, while diameter of damping hole of control cover plate has influence on the building and relieving pressure of the system.

Originality/value

The research results provide powerful theoretical support for the parametric design of the cartridge electromagnetic relief valve in the hydraulic system of plate shearing machine.

Details

International Journal of Structural Integrity, vol. 9 no. 1
Type: Research Article
ISSN: 1757-9864

Keywords

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Article
Publication date: 13 April 2010

Guangcheng Dong, Xu Chen, Xinjian Zhang, Khai D.T. Ngo and Guo-Quan Lu

The purpose of this paper is to study the phenomenology of Al2O3-DBC substrate thermal-cracking under different high temperature cyclic loadings. The extremely low cycle fatigue…

730

Abstract

Purpose

The purpose of this paper is to study the phenomenology of Al2O3-DBC substrate thermal-cracking under different high temperature cyclic loadings. The extremely low cycle fatigue (ELCF) life prediction model for ductile materials was used to describe the thermal fatigue life of Al2O3-DBC substrates.

Design/methodology/approach

Four groups of thermal cycling tests using Al2O3-DBC substrates with 0.65 mm thick copper were conducted using different peak temperatures. The failure samples were observed by optical microscope. The thermal plastic strain distribution in the Al2O3-DBC substrates was analyzed using a finite element method with the Chaboche model for describing plastic deformation of copper. The ELCF life prediction model was used to predict the life of Al2O3-DBC substrates under high temperature cyclic loadings.

Findings

Interface cracking was observed to initiate at the short edge of the bonded copper and deviated into the ceramic layer when the crack grew beyond the critical length of 0.1-0.8 mm. The interface crack deviated into the ceramic layer at different thickness and grew parallel to the interface layer between the ceramic layer and copper layer. The crack propagation stopped after certain cycles. The copper layer with 10-20 μm thick alumina inside was not split away totally from the ceramic layer. The ELCF life prediction model could predict the life of Al2O3-DBC substrates well under high temperature cyclic loading. The material constants in the extremely low fatigue life prediction model were obtained using thermal fatigue tests results.

Research limitations/implications

The influence of copper layer thickness and ceramic layer thickness on thermal cracking characteristics of DBC substrate should be studied in the future. Failure models should also be further investigated.

Originality/value

The failure model of Al2O3-DBC substrates under high temperature cyclic loading was studied. A method for predicting the life of the substrate samples under high temperature cyclic loading was proposed.

Details

Soldering & Surface Mount Technology, vol. 22 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

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Book part
Publication date: 7 October 2024

Zhen Zhang

This chapter examines the ‘embodied turn’ in the study of traditional Chinese sports and identifies issues within this area of research. It introduces new interpretative…

Abstract

This chapter examines the ‘embodied turn’ in the study of traditional Chinese sports and identifies issues within this area of research. It introduces new interpretative perspectives and approaches within the framework of bodily sociology to elucidate the link between locally-informed sports practices and the formation of socialized individuals. The chapter categorises the current research into three main themes: self-giving, the creation of bodily value and the construction of national identity through sports. It then integrates these themes with the findings of embodied sociology. The chapter compiles and analyzes the existing literature on traditional Chinese sports culture from both Chinese and international scholars, offering insights into the status, rationale and challenges of bodily sociological research. By contextualising the concept of the embodied turn in traditional Chinese sports culture – through concepts such as self-givenness, self-techniques, the generation of value and the creation of collective memory – the chapter discusses the impact of bodily sociology on cultural research. The chapter advocates for further bodily sociological studies of Chinese sports culture, which could enhance the understanding of Chinese studies among Western scholars and contribute to a genuine embodied turn in this field of study. Providing one of the initial explorations of embodied studies in traditional Chinese sports, the chapter reveals a transition from broad cultural interpretations and symbolic, structuralist sociology to a phenomenological approach in sports cultural studies. It posits that the bodily sociology approach is beneficial for sports studies although current research has not yet fully realized the embodied turn.

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Article
Publication date: 25 October 2021

Xinjian Ma, Shiqian Liu, Huihui Cheng and Weizhi Lyu

This paper aims to focus on the sensor fault-tolerant control (FTC) for civil aircraft under exterior disturbance.

171

Abstract

Purpose

This paper aims to focus on the sensor fault-tolerant control (FTC) for civil aircraft under exterior disturbance.

Design/methodology/approach

First, a three-step cubature Kalman filter (TSCKF) is designed to detect and isolate the sensor fault and to reconstruct the sensor signal. Meanwhile, a nonlinear disturbance observer (NDO) is designed for disturbance estimation. The NDO and the TSCKF are combined together and an NDO-TSCKF is proposed to solve the problem of sensor faults and bounded disturbances simultaneously. Furthermore, an FTC scheme is designed based on the nonlinear dynamic inversion (NDI) and the NDO-TSCKF.

Findings

The method is verified by a Cessna 172 aircraft model under bias gyro fault and constant angular rate disturbance. The proposed NDO-TSCKF has the ability of signal reconstruction and disturbance estimation. The proposed FTC scheme is also able to solve the sensor fault and disturbance simultaneously.

Research limitations/implications

NDO-TSCKF is the novel algorithm used in sensor signal reconstruction for aircraft. Then, disturbance observer-based FTC can improve the flight control system performances when the system with faults.

Practical implications

The NDO-TSCKF-based FTC scheme can be used to solve the sensor fault and exterior disturbance in flight control. For example, the bias gyro fault with constant angular rate disturbance of a civil aircraft is studied.

Social implications

Signal reconstruction for critical sensor faults and disturbance observer-based FTC for civil aircraft are useful in modern civil aircraft design and development.

Originality/value

This is the research paper studies on the signal reconstruction and FTC scheme for civil aircraft. The proposed NDO-TSCKF is better than the current reconstruction filter because the failed sensor signal can be reconstructed under disturbances. This control scheme has a better fault-tolerant capability for sensor faults and bounded disturbances than using regular NDI control.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

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