Special Issue "Power Transmission and Control in Power and Vehicle Machineries"

A special issue of Applied Sciences (ISSN 2076-3417). This special issue belongs to the section "Mechanical Engineering".

Deadline for manuscript submissions: closed (28 February 2018)

Special Issue Editors

Lead Guest Editor
Prof. Dr. Yunhua Li

Department of Mechanical and Electronic Engineering, Beihang University, Beijing100191, China
E-Mail
Interests: non-linearity dynamics; hydraulic servo control; mechatronic control systems; non-linear vibration and control; transmission and control of aircraft, mobile robots, and vehicles
Co-Guest Editor
Prof. Dr. Nariman Sepehri

Department of Mechanical Engineering, University of Manitoba, Winnipeg, MB R3T 5V6, Canada
E-Mail
Interests: teleoperation and robotics; control systems, systems modelling and identification; and actuators and fluid power
Co-Guest Editor
Prof. Dr. Kazuhisa Ito

Department of Machinery and Control Systems, Shibaura Institute of Technology, Saitama 337-8570, Japan
E-Mail
Interests: nonlinear control system design and their applications; improving control and energy saving performance of fluid power systems, including aqua drive system (ADS); agriculture engineering
Co-Guest Editor
Prof. Dr. Maolin Cai

Department of Mechanical and Electronic Engineering, Beihang University, Beijing100191, China
E-Mail
Interests: energy saving performance of fluid power systems, energy conversion and management technologies of compressed air systems and compressed air powered vehicles; respiratory support therapy technologies based on pneumatic systems
Co-Guest Editor
Prof. Dr. Bing Xu

Department of Mechanical and Electronic Engineering, Zhejiang University, Hangzhou 310058, China
E-Mail
Interests: hydraulic components; electro-hydraulic control; energy saving and noise reduction of mechatronics system
Co-Guest Editor
Dr. Yan Shi

Department of Mechanical and Electronic Engineering, Beihang University, Beijing100191, China
E-Mail
Interests: energy-saving technologies of pneumatic systems; energy conversion and management technologies of compressed air systems and compressed air powered vehicles; respiratory support therapy technologies based on pneumatic systems

Special Issue Information

Dear Colleagues,

The topic of this Special Issue concerns the latest achievements and investigations in power transmission and control with a focus on power and vehicle machinery.

Power transmission and control include the conversion, transmission, and distribution of power, and motion control, and it is a key technology and design theory of vehicle machines, such as automobile and construction machinery, airplanes, and ships. The concrete engineering realizations of power transmission and control consist of hydraulic, pneumatic, electro-hydraulic, electro-pneumatic, and hydrodynamic transmission. Power transmission and control has also been widely used in power engineering, such as wind power generation systems, hydroelectric power systems, solar power systems, compressed air energy storage systems, hybrid energy vehicles, and hydrogen energy vehicles. By using advanced control strategies and optimization methods, the performances of power transmission and control systems in power and vehicle machinery can be significantly improved.

Nowadays, there have been many achievements in fluid power transmission and control in power and vehicle machinery. As an effort to disseminate current advances, we are very pleased to organize this Special Issue, which will be published in Applied Sciences, which is an international journal indexed in the Science Citation Index Expanded (IF:1.679; https://www.mdpi.com/journal/applsci/). The submitted manuscripts should contain both theoretical and practical/experimental results and will be subject to peer-review procedures. Potential topics include, but are not limited to:

  • Mechatronics methodology in fluid power transmission and control

  • Saving energy and energy utilization technologies in energy resource machinery, vehicles, construction machinery, and aircraft

  • Condition monitoring and health management of power and vehicle machinery

  • Lower friction materials, lubrication, heat generation, and thermal control in fluid power components

  • Sensor network and data fusion in fluid power control system and power distribution systems

  • Novel actuation, transmission, and control techniques in energy resources and vehicle machinery

  • Fluid transmission technology application in healthcare machinery

  • Energy synthesis utilization and energy management in aircraft utility systems

  • Modelling simulations and optimization designs in fluid power transmission and control

Prof. Dr. Yunhua Li
Prof. Dr. Nariman Sepehri
Prof. Dr. Kazuhisa Ito
Prof. Dr. Maolin Cai
Prof. Dr. Bing Xu
Dr. Yan Shi
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Applied Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1500 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • fluid power transmission and control

  • vehicle machineries

  • mechatronics methodology

  • health management

Published Papers (18 papers)

View options order results:
result details:
Displaying articles 1-18
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle A Simplified Methodology to Evaluate the Design Specifications of Hydraulic Components
Appl. Sci. 2018, 8(9), 1612; https://doi.org/10.3390/app8091612
Received: 29 July 2018 / Revised: 30 August 2018 / Accepted: 6 September 2018 / Published: 11 September 2018
PDF Full-text (2914 KB) | HTML Full-text | XML Full-text
Abstract
The fatigue of a hydraulic component inherently varies due to various factors that can be divided into two categories: structural and load spectrum variability. The effects of both variabilities must be considered when determining fatigue life. Compared with the structural variability, determining the [...] Read more.
The fatigue of a hydraulic component inherently varies due to various factors that can be divided into two categories: structural and load spectrum variability. The effects of both variabilities must be considered when determining fatigue life. Compared with the structural variability, determining the variability in the load spectrums is more difficult because the service conditions are complicated and the measurements of the load parameters are slow and expensive. The problem that arises when studying the fatigue behaviour of such components is the transferability of short data samples from real-life load histories, which are application-dependant, to laboratory test methods. Derived from the experimental background and know-how of the authors, this paper proposes a methodology that allows the definition and establishment of the hydraulic cylinder design specificactions, while taking into account the probabilistic characterisation of the load spectrum variability. This methodology could be extrapolated to other hydraulic or mechanical components. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Open AccessArticle Development of Proportional Pressure Control Valve for Hydraulic Braking Actuator of Automobile ABS
Appl. Sci. 2018, 8(4), 639; https://doi.org/10.3390/app8040639
Received: 25 February 2018 / Revised: 14 April 2018 / Accepted: 17 April 2018 / Published: 20 April 2018
Cited by 1 | PDF Full-text (7586 KB) | HTML Full-text | XML Full-text
Abstract
This research developed a novel proportional pressure control valve for an automobile hydraulic braking actuator. It also analyzed and simulated solenoid force of the control valves, and the pressure relief capability test of electromagnetic thrust with the proportional valve body. Considering the high [...] Read more.
This research developed a novel proportional pressure control valve for an automobile hydraulic braking actuator. It also analyzed and simulated solenoid force of the control valves, and the pressure relief capability test of electromagnetic thrust with the proportional valve body. Considering the high controllability and ease of production, the driver of this proportional valve was designed with a small volume and powerful solenoid force to control braking pressure and flow. Since the proportional valve can have closed-loop control, the proportional valve can replace a conventional solenoid valve in current brake actuators. With the proportional valve controlling braking and pressure relief mode, it can narrow the space of hydraulic braking actuator, and precisely control braking force to achieve safety objectives. Finally, the proposed novel proportional pressure control valve of an automobile hydraulic braking actuator was implemented and verified experimentally. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Open AccessArticle Development of a High-Pressure Pneumatic On/Off Valve with High Transient Performances Direct-Driven by Voice Coil Motor
Appl. Sci. 2018, 8(4), 611; https://doi.org/10.3390/app8040611
Received: 12 February 2018 / Revised: 3 April 2018 / Accepted: 3 April 2018 / Published: 12 April 2018
Cited by 2 | PDF Full-text (10557 KB) | HTML Full-text | XML Full-text
Abstract
The high-speed pneumatic on/off valve is one of the critical components in pneumatic systems, which has been widely investigated in the last decades. In this research, a new voice coil motor direct drive high-speed pneumatic on/off valve (VCM-DHPV) is proposed, and the mathematical [...] Read more.
The high-speed pneumatic on/off valve is one of the critical components in pneumatic systems, which has been widely investigated in the last decades. In this research, a new voice coil motor direct drive high-speed pneumatic on/off valve (VCM-DHPV) is proposed, and the mathematical model of VCM-DHPV, which consists of the fluid subsystem and electro-mechanical subsystem, is established. In addition, the key structural parameters of VCM-DHPV are optimized through the simulation analysis to improve its dynamic performance. The experiment results show that the developed VCM-DHPV has a good sealing performance by adopting the face-seal type in the valve port, and a large flow rate up to 5500 L/min, and its opening response time is 8.2 ms under the gas supply pressure of 8 MPa and exiting voltage of 240 V. With the supply pressure and the exciting voltage rising, the opening response time of VCM-DHPV is gradually increasing, and the variation tendency of the spool displacement curves is in accordance with the simulation results. This research will have significantly effects on raising the performance of the high-speed pneumatic on/off valve and the development of pneumatic precision motion control. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Graphical abstract

Open AccessArticle Investigation on the Effects of Internal EGR by Variable Exhaust Valve Actuation with Post Injection on Auto-ignited Combustion and Emission Performance
Appl. Sci. 2018, 8(4), 597; https://doi.org/10.3390/app8040597
Received: 19 February 2018 / Revised: 8 April 2018 / Accepted: 9 April 2018 / Published: 10 April 2018
Cited by 1 | PDF Full-text (18325 KB) | HTML Full-text | XML Full-text
Abstract
Variable valve mechanisms are usually applied to a gasoline combustion engine to improve its power performance by controlling the amount of intake air according to the operating load. These mechanisms offer one possibility of resolving the conflict of objectives between a further reduction [...] Read more.
Variable valve mechanisms are usually applied to a gasoline combustion engine to improve its power performance by controlling the amount of intake air according to the operating load. These mechanisms offer one possibility of resolving the conflict of objectives between a further reduction of raw emissions and an improvement in fuel efficiency. In recent years, variable valve control systems have become extremely important in the diesel combustion engine. Importantly, it has been shown that there are several potential benefits of applying variable valve timing (VVT) to a compression ignition engine. Valve train variability could offer one option to achieve the reduction goals of engine-out emissions and fuel consumption. The aim of this study was to investigate the effects on part load combustion and emission performance of internal exhaust gas recirculation (EGR) by variable exhaust valve lift actuation using a cam-in-cam system, which is an electronically variable valve device with a variable inside cam retarded to about 30 degrees. Numerical simulation based on GT-POWER has been performed to predict the NOx reduction strategy at the part load operating point of 1200 rpm in a four-valve diesel engine. A GT-POWER model of a common-rail direct injection engine with internal EGR was built and verified with experimental data. As a result, large potential for reducing NOx emissions through the use of exhaust valve control has been identified. Namely, it is possible to utilize heat efficiently as recompression of retarded post injection with downscaled specification of the exhaust valve rather than the intake valve, even if the CIC V1 condition with a reduction of the exhaust valve has a higher internal EGR rate of about 2% compared to that of the CIC V2 condition. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Open AccessArticle Novel Automatic Idle Speed Control System with Hydraulic Accumulator and Control Strategy for Construction Machinery
Appl. Sci. 2018, 8(4), 496; https://doi.org/10.3390/app8040496
Received: 23 January 2018 / Revised: 6 March 2018 / Accepted: 19 March 2018 / Published: 26 March 2018
PDF Full-text (9777 KB) | HTML Full-text | XML Full-text
Abstract
To reduce the energy consumption and emissions of the hydraulic excavator, a two-level idle speed control system with a hydraulic accumulator for the construction machinery is proposed to reduce the energy consumption and improve the control performance of the actuator when the idle [...] Read more.
To reduce the energy consumption and emissions of the hydraulic excavator, a two-level idle speed control system with a hydraulic accumulator for the construction machinery is proposed to reduce the energy consumption and improve the control performance of the actuator when the idle mode is cancelled. The structure and working principle are analyzed. The hydraulic accumulator (HA) is used to store the energy, which can provide backup pressured fluid when the idle mode is cancelled. Then, a method of how to set the pressure differential between the hydraulic accumulator and the load is proposed and the control law is discussed. The test rig is built. The experimental result shows that the idle speed can be switched among the first idle speed, the second idle speed and the normal speed automatically. Though the idle speed in the novel system can be reduced more than that in the conventional automatic idle speed control system (AISCS), the proposed system can still build the actuator pressure more quickly when the idle mode is cancelled. When compared to the system without the idle speed control, the energy saving of the proposed system is about 67%. The proposed two-level idle speed control system with a HA can achieve a high energy efficiency and a good control performance. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Graphical abstract

Open AccessArticle Pneumatic Rotary Actuator Position Servo System Based on ADE-PD Control
Appl. Sci. 2018, 8(3), 406; https://doi.org/10.3390/app8030406
Received: 17 January 2018 / Revised: 5 March 2018 / Accepted: 5 March 2018 / Published: 9 March 2018
Cited by 2 | PDF Full-text (4453 KB) | HTML Full-text | XML Full-text
Abstract
In order to accurately control the rotation position of a pneumatic rotary actuator, the flow state of the gas and the motion state of the pneumatic rotary actuator in the pneumatic rotary actuator position servo system are analyzed in this paper. The mathematical [...] Read more.
In order to accurately control the rotation position of a pneumatic rotary actuator, the flow state of the gas and the motion state of the pneumatic rotary actuator in the pneumatic rotary actuator position servo system are analyzed in this paper. The mathematical model of the system and the experiment platform are established after that. An Adaptive Differential Evolution (ADE) algorithm which adaptively ameliorates the scaling factor and crossover probability in the process of individual evolution is proposed and applied to the parameter optimization of PD controller. The experimental platform is used to compare the controller with Differential Evolution (DE) algorithm and NCD-PID controller. Finally, the characteristics of the system are tested by increasing the inertial load. The experimental results illustrate that system using ADE-PD control strategy has greater position precision and faster response than using DE-PD and NCD-PID strategies, and shows great robustness. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Graphical abstract

Open AccessArticle Pressure Transient Model of Water-Hydraulic Pipelines with Cavitation
Appl. Sci. 2018, 8(3), 388; https://doi.org/10.3390/app8030388
Received: 15 February 2018 / Revised: 1 March 2018 / Accepted: 1 March 2018 / Published: 7 March 2018
Cited by 2 | PDF Full-text (925 KB) | HTML Full-text | XML Full-text
Abstract
Transient pressure investigation of water-hydraulic pipelines is a challenge in the fluid transmission field, since the flow continuity equation and momentum equation are partial differential, and the vaporous cavitation has high dynamics; the frictional force caused by fluid viscosity is especially uncertain. In [...] Read more.
Transient pressure investigation of water-hydraulic pipelines is a challenge in the fluid transmission field, since the flow continuity equation and momentum equation are partial differential, and the vaporous cavitation has high dynamics; the frictional force caused by fluid viscosity is especially uncertain. In this study, due to the different transient pressure dynamics in upstream and downstream pipelines, the finite difference method (FDM) is adopted to handle pressure transients with and without cavitation, as well as steady friction and frequency-dependent unsteady friction. Different from the traditional method of characteristics (MOC), the FDM is advantageous in terms of the simple and convenient computation. Furthermore, the mechanism of cavitation growth and collapse are captured both upstream and downstream of the water-hydraulic pipeline, i.e., the cavitation start time, the end time, the duration, the maximum volume, and the corresponding time points. By referring to the experimental results of two previous works, the comparative simulation results of two computation methods are verified in experimental water-hydraulic pipelines, which indicates that the finite difference method shows better data consistency than the MOC. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Open AccessArticle Dimensionless Energy Conversion Characteristics of an Air-Powered Hydraulic Vehicle
Appl. Sci. 2018, 8(3), 347; https://doi.org/10.3390/app8030347
Received: 11 February 2018 / Revised: 22 February 2018 / Accepted: 23 February 2018 / Published: 28 February 2018
PDF Full-text (3401 KB) | HTML Full-text | XML Full-text
Abstract
Due to the advantages of resource conservation and less exhaust emissions, compressed air-powered vehicle has attracted more and more attention. To improve the power and efficiency of air-powered vehicle, an air-powered hydraulic vehicle was proposed. As the main part of the air-powered hydraulic [...] Read more.
Due to the advantages of resource conservation and less exhaust emissions, compressed air-powered vehicle has attracted more and more attention. To improve the power and efficiency of air-powered vehicle, an air-powered hydraulic vehicle was proposed. As the main part of the air-powered hydraulic vehicles, HP transformer (short for Hydropneumatic transformer) is used to convert the pneumatic power to higher hydraulic power. In this study, to illustrate the energy conversion characteristics of air-powered hydraulic vehicle, dimensionless mathematical model of the vehicle’s working process was set up. Through experimental study on the vehicle, the dimensionless model was verified. Through simulation study on the vehicle, the following can be obtained: firstly, the increase of the hydraulic chamber orifice and the area ratio of the pistons can lead to a higher output power, while output pressure is just the opposite. Moreover, the increase of the output pressure and the aperture of the hydraulic chamber can lead to a higher efficiency, while area ratio of the pistons played the opposite role. This research can be referred to in the performance and design optimization of the HP transformers. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Open AccessArticle Prescribed Performance Constraint Regulation of Electrohydraulic Control Based on Backstepping with Dynamic Surface
Appl. Sci. 2018, 8(1), 76; https://doi.org/10.3390/app8010076
Received: 16 November 2017 / Revised: 25 December 2017 / Accepted: 25 December 2017 / Published: 8 January 2018
Cited by 3 | PDF Full-text (880 KB) | HTML Full-text | XML Full-text
Abstract
In electro-hydraulic system (EHS), uncertain nonlinearities such as some hydraulic parametric uncertainties and external load disturbance often degrade the output dynamic performance. To address this problem, a prescribed performance constraint (PPC) control method is adopted in EHS to restrict the tracking position error [...] Read more.
In electro-hydraulic system (EHS), uncertain nonlinearities such as some hydraulic parametric uncertainties and external load disturbance often degrade the output dynamic performance. To address this problem, a prescribed performance constraint (PPC) control method is adopted in EHS to restrict the tracking position error of the cylinder position to a prescribed accuracy and guarantee the dynamic and steady position response in a required boundedness under these uncertain nonlinearities. Furthermore, a dynamic surface is designed to avoid the explosion of complexity due to the repeatedly calculated differentiations of the virtual control variables derived in backstepping. The effectiveness of the proposed controller has been verified by a comparative results. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Open AccessArticle A Performance Test and Internal Flow Field Simulation of a Vortex Pump
Appl. Sci. 2017, 7(12), 1273; https://doi.org/10.3390/app7121273
Received: 17 September 2017 / Revised: 29 November 2017 / Accepted: 1 December 2017 / Published: 7 December 2017
Cited by 1 | PDF Full-text (5302 KB) | HTML Full-text | XML Full-text
Abstract
Vortex pumps have good non-clogging performance and are widely used in the fluid transportation of food, sewage treatment, and mineral and coal slurry transportation. In order to design and manufacture a vortex pump with good performance and establish a method of optimum design, [...] Read more.
Vortex pumps have good non-clogging performance and are widely used in the fluid transportation of food, sewage treatment, and mineral and coal slurry transportation. In order to design and manufacture a vortex pump with good performance and establish a method of optimum design, we must master the internal flow rules of the pump. Based on the self-design vortex pump (32WB8-12) experiment, the discharge-pump head (qv-H), discharge-pump shaft power (qv-P), discharge-pump efficiency (qv-η), and discharge-critical net positive suction head (qv-NPSHc) curves are obtained, and the qv-NPSHc curve shows an opposite tendency compared with the centrifugal pump. With the mathematical model selected with respect to the optimal condition, the three-dimensional internal flow within the vortex pump has been numerically simulated by a renormalization group k-ε (RNG k-ε) turbulence model. The static pressure (ps) and velocity distribution of the impeller and the middle section of the volute at 0°, 90°, 180°, and 270° are obtained, and the performance curves have been fitted using a CFX-calculated energy parameter. It was illustrated that the velocity field is relatively disordered and the flow in the impeller region is of a forced vortex character. The flow in the volute is similar to that of the combined vortex with backflow, which is a non-axisymmetric unsteady flow with quite high turbulence intensity. These factors are the main reasons for the relatively low efficiency of the vortex pump. The measurement of flow field in volute with a five-hole probe was conducted, and it is demonstrated that the numerical results are in good agreement with the flow field measurement data. An upward pressure gradient forms in the portal area of the impeller, and it is confirmed that the lowest pressure point is located in the upper position of the impeller hub. It is revealed that for the vortex pump to have advanced suction and anti-cavitation performance, the lowest pressure in the pump should be −4 × 104 Pa and it should be located at the center of the vortex chamber cavity. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Open AccessArticle Modeling and Dynamic Analysis on the Direct Operating Solenoid Valve for Improving the Performance of the Shifting Control System
Appl. Sci. 2017, 7(12), 1266; https://doi.org/10.3390/app7121266
Received: 7 November 2017 / Revised: 27 November 2017 / Accepted: 1 December 2017 / Published: 5 December 2017
Cited by 1 | PDF Full-text (5300 KB) | HTML Full-text | XML Full-text
Abstract
The dynamic characteristics and energy loss in a shifting control system is important and necessary in the performance improvement of an automatic transmission. The direct operating solenoid valve has been considered as a potential component applying in the shifting control system in vehicle. [...] Read more.
The dynamic characteristics and energy loss in a shifting control system is important and necessary in the performance improvement of an automatic transmission. The direct operating solenoid valve has been considered as a potential component applying in the shifting control system in vehicle. The previous method can solve only a specific physical field or use the test results of the magnetic force as input curve. The paper presents a numerical approach for solving the multi-domain physical problem of the valve. A precise model of the direct acting solenoid valve considering different physical field is developed. An experimental study is also performed to evaluate and confirm the simulation. Based on the model, the influences on the dynamic characteristics of the valve are analyzed by calculating forces acting on the valve. The systematic analysis of forces and energy loss characteristics are performed for three different flow conditions varying clearance height from 10 µm to 30 µm. The results demonstrate that the pressure response time can be improved with smaller clearance between the spool and the sleeve. Moreover, the leakage of the shifting control system employing the direct acting solenoid valve can be reduced by 60% compared to the conventional two-stage pilot valve in our previous product. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Open AccessArticle Theoretical Analysis for the Flow Ripple of a Tandem Crescent Pump with Index Angles
Appl. Sci. 2017, 7(11), 1148; https://doi.org/10.3390/app7111148
Received: 16 October 2017 / Revised: 31 October 2017 / Accepted: 3 November 2017 / Published: 8 November 2017
PDF Full-text (9182 KB) | HTML Full-text | XML Full-text
Abstract
This paper presents a theoretical approach for lowering the outlet flow ripple of a crescent pump by applying a tandem crescent pump consisting of two gear pairs with an index angle between them. The outlet flow of the tandem pump is obtained by [...] Read more.
This paper presents a theoretical approach for lowering the outlet flow ripple of a crescent pump by applying a tandem crescent pump consisting of two gear pairs with an index angle between them. The outlet flow of the tandem pump is obtained by summing the flow produced by the two gear pairs, and the flow ripple of the tandem pump can be attenuated by properly selecting the design parameters in terms of the index angle and the displacement ratio between the two gear pairs. A lumped parameter model is presented for evaluating the crescent pump’s flow ripples, and experiments were performed on a single crescent pump to validate the model from the aspects of the steady-state flow-pressure characteristics and the outlet pressure ripples. In this way, the main causes of the flow ripple could be identified by comparing the kinematic flow with the actual flow evaluated by the model. Additionally, simulation results suggested that a tandem pump with an index angle of 13.85° and displacement ratio of 0.5 could lead to a more than 45% decrease in the outlet flow ripple than a single pump with the same displacement in a wide range of operating conditions. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Graphical abstract

Open AccessArticle A New Method for Analysing the Pressure Response Delay in a Pneumatic Brake System Caused by the Influence of Transmission Pipes
Appl. Sci. 2017, 7(9), 941; https://doi.org/10.3390/app7090941
Received: 29 July 2017 / Revised: 2 September 2017 / Accepted: 9 September 2017 / Published: 13 September 2017
Cited by 2 | PDF Full-text (3690 KB) | HTML Full-text | XML Full-text
Abstract
This study aims to propose an analysis method for resolving the pressure response of a pneumatic brake circuit considering the effect of a transmission pipe. Pneumatic brake systems (PBS) are widely used in commercial vehicles. The pressure response characteristic of the PBS is [...] Read more.
This study aims to propose an analysis method for resolving the pressure response of a pneumatic brake circuit considering the effect of a transmission pipe. Pneumatic brake systems (PBS) are widely used in commercial vehicles. The pressure response characteristic of the PBS is the key factor affecting braking performance. By using the thermodynamics of a variable-quality system, the pressure response model of the brake chamber is established, which includes the dynamic model of the pipe considering the unsteady friction and heat transfer. The partial-differential control equations of pipe are solved by introducing the constrained interpolation profile (CIP) method, and a virtual chamber model is proposed to set the boundary condition so as to solve the pressure response in the brake chamber simultaneously. Thus, the regularity of the brake pressure response is obtained by considering the influence of the pipe. Lastly, the model is verified experimentally. The present study indicates that the main factors that affect the pressure response delay are the pipe length and the combination forms of the sonic conductances of the orifices inlet and outlet. Furthermore, it helps to verify that the CIP method is an effective way of solving the pressure response of a brake circuit because of its high accuracy. The present study serves as a foundation for the design and analysis of a PBS. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Open AccessArticle Analysis of the Energy Efficiency of a Pneumatic Booster Regulator with Energy Recovery
Appl. Sci. 2017, 7(8), 816; https://doi.org/10.3390/app7080816
Received: 27 June 2017 / Revised: 27 July 2017 / Accepted: 7 August 2017 / Published: 9 August 2017
Cited by 3 | PDF Full-text (11094 KB) | HTML Full-text | XML Full-text
Abstract
Pneumatic booster regulators (PBR) are in great demand in modern pneumatic systems for their energy-saving abilities. A new booster regulator with energy recovery (VBA-R) was proposed, and its energy efficiency was investigated by introducing the concept of air power. On the basis of [...] Read more.
Pneumatic booster regulators (PBR) are in great demand in modern pneumatic systems for their energy-saving abilities. A new booster regulator with energy recovery (VBA-R) was proposed, and its energy efficiency was investigated by introducing the concept of air power. On the basis of quality-alterable gas thermodynamics, an energy efficiency assessment and pressure response model for VBA-R was proposed. First, a model was solved using MATLAB/Simulink software, and an alternative experiment was designed to verify the mathematical model and performance improvement. The results showed that the simulation was consistent with the experiment. We also can conclude that, first of all, the energy efficiency decreases with the increasing of supply pressure and flow-rate consumption; a VBA-R has the highest efficiency when its diameter ratio is closest to 1.3. Finally, a recovery chamber helped to improve the performance of the VBA-R, which included a boost ratio improvement of 15–25% and an efficiency improvement of 5–10% compared with a conventional VBA booster regulator. This research lays the foundation for optimism regarding the proposed booster regulator. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Open AccessArticle An Experimental Study on Hysteresis Characteristics of a Pneumatic Braking System for a Multi-Axle Heavy Vehicle in Emergency Braking Situations
Appl. Sci. 2017, 7(8), 799; https://doi.org/10.3390/app7080799
Received: 27 June 2017 / Revised: 24 July 2017 / Accepted: 2 August 2017 / Published: 6 August 2017
Cited by 3 | PDF Full-text (6343 KB) | HTML Full-text | XML Full-text
Abstract
This study aims to investigate the hysteresis characteristics of a pneumatic braking system for multi-axle heavy vehicles (MHVs). Hysteresis affects emergency braking performance severely. The fact that MHVs have a large size and complex structure leads to more nonlinear coupling property of the [...] Read more.
This study aims to investigate the hysteresis characteristics of a pneumatic braking system for multi-axle heavy vehicles (MHVs). Hysteresis affects emergency braking performance severely. The fact that MHVs have a large size and complex structure leads to more nonlinear coupling property of the pneumatic braking system compared to normal two-axle vehicles. Thus, theoretical analysis and simulation are not enough when studying hysteresis. In this article, the hysteresis of a pneumatic brake system for an eight-axle vehicle in an emergency braking situation is studied based on a novel test bench. A servo drive device is applied to simulate the driver’s braking intensions normally expressed by opening or moving speed of the brake pedal. With a reasonable arrangement of sensors and the NI LabVIEW platform, both the delay time of eight loops and the response time of each subassembly in a single loop are detected in real time. The outcomes of the experiment show that the delay time of each loop gets longer with the increase of pedal opening, and a quadratic relationship exists between them. Based on this, the pressure transient in the system is fitted to a first-order plus time delay model. Besides, the response time of treadle valve and controlling pipeline accounts for more than 80% of the loop’s total delay time, indicating that these two subassemblies are the main contributors to the hysteresis effect. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Graphical abstract

Open AccessArticle Energy Regeneration Hydraulic System via a Relief Valve with Energy Regeneration Unit
Appl. Sci. 2017, 7(6), 613; https://doi.org/10.3390/app7060613
Received: 21 April 2017 / Revised: 9 June 2017 / Accepted: 9 June 2017 / Published: 13 June 2017
Cited by 3 | PDF Full-text (4102 KB) | HTML Full-text | XML Full-text
Abstract
Relief valves are widely used in industrial machinery. Due to the outlet of the relief valve being connected to the tank, the pressure drop of the relief valve is frequently equal to the inlet pressure. Accordingly, the energy loss of the relief valve [...] Read more.
Relief valves are widely used in industrial machinery. Due to the outlet of the relief valve being connected to the tank, the pressure drop of the relief valve is frequently equal to the inlet pressure. Accordingly, the energy loss of the relief valve is very high in some cases and this will worsen with an increase in the rated pressure of the hydraulic system. In order to overcome the disadvantage of overflow energy loss in a relief valve, a hydraulic energy regeneration unit (HERU) is connected to the outlet of the relief valve to decrease the pressure drop between the inlet and outlet of the relief valve. The overflow loss, which is characterized by the pressure drop, can be reduced accordingly. The approach is to convert the overflow energy loss in hydraulic form and allow for release when needed. The configuration and working principle of the relief valve with HERU is introduced in this present study. The mathematical model is established to obtain the factors influencing the stability of the relief valve. The working pressure of the hydraulic accumulator (HA) is explored. Furthermore, the control process of the operating state of the HA is scheduled to decide whether to regenerate the energy via the HERU. The software AMESim is utilized to analyze the performance and characteristics of the relief valve with HERU. Following this, the test rig is built and used to verify the effectiveness of the proposed relief valve with HERU. The experimental results show that the relief valve with the HERU connected to its outlet can still achieve better pressure-regulating characteristics. The energy regeneration efficiency saved by the HA is up to 83.6%, with a higher pre-charge pressure of the HA. This indicates that the proposed structure of the relief valve with HERU can achieve a better performance and higher regeneration efficiency. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Review

Jump to: Research

Open AccessReview Review on Inlet/Outlet Oil Coordinated Control for Electro-Hydraulic Power Mechanism under Sustained Negative Load
Appl. Sci. 2018, 8(6), 886; https://doi.org/10.3390/app8060886
Received: 26 April 2018 / Revised: 20 May 2018 / Accepted: 23 May 2018 / Published: 28 May 2018
PDF Full-text (1942 KB) | HTML Full-text | XML Full-text
Abstract
Speed control and smooth regulation in an electro-hydraulic motion control system under negative load (over-running load) are crucial to mobile machineries, vehicles, and motion simulation equipment. Problems, such as bad natural stability, bad dynamic performance for small adjusting signal, serious coupling, and difficulty [...] Read more.
Speed control and smooth regulation in an electro-hydraulic motion control system under negative load (over-running load) are crucial to mobile machineries, vehicles, and motion simulation equipment. Problems, such as bad natural stability, bad dynamic performance for small adjusting signal, serious coupling, and difficulty to coordinate between speed smoothness and speed regulation, exist in traditional valve-controlled and pump-controlled electro-hydraulic power mechanism. The coordinated motion control scheme, which is based on independent regulation of inlet/outlet oil for electro-hydraulic power mechanism has attracted the attention of many scholars. In the last two decades, many progresses had been made in coordinated control technology, employing in inlet/outlet independent metering and pump/valves independent regulation. Moreover, the technology has been widely used in the electro-hydraulic operating system in hydraulic excavator and the speed smoothness control system in heavy transport vehicles. In this study, recent advancements and upcoming trends in coordinated control and inlet/outlet independent metering for electro-hydraulic power mechanism under sustained negative load are reviewed. Firstly, related research advancements are summarized, including flow rate regulation mechanism based on inlet/outlet coordinated control, coordinated control strategy and nonlinear control method of electro-hydraulic control system. Then, nonlinear modeling of inlet/outlet independent metering and pump/valves independent regulation in electro-hydraulic control system is presented. In addition, the electro-hydraulic speed smoothness control and energy recovery for heavy engineering vehicles under long down-slope is discussed and reviewed. Finally, existing problems and future trends of inlet/outlet coordinated control for an electro-hydraulic power mechanism under sustained negative load are presented. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Graphical abstract

Open AccessReview Research Progress of Related Technologies of Electric-Pneumatic Pressure Proportional Valves
Appl. Sci. 2017, 7(10), 1074; https://doi.org/10.3390/app7101074
Received: 1 September 2017 / Accepted: 27 September 2017 / Published: 17 October 2017
Cited by 4 | PDF Full-text (3982 KB) | HTML Full-text | XML Full-text
Abstract
Because of its cleanness, safety, explosion proof, and other characteristics, pneumatic technologies have been applied in numerous industrial automation fields. As a key controlling element of a pneumatic system, electric-pneumatic pressure proportional valves have attracted the attention of many scholars in recent years. [...] Read more.
Because of its cleanness, safety, explosion proof, and other characteristics, pneumatic technologies have been applied in numerous industrial automation fields. As a key controlling element of a pneumatic system, electric-pneumatic pressure proportional valves have attracted the attention of many scholars in recent years. In this paper, in order to illustrate the research status and the development trend of electric-pneumatic pressure proportional valves, firstly, several related technologies will be introduced, for example, simulation methods and experimental modes. In addition, controlling methods, structural styles, and feedback forms are also compared in several types of pressure proportional valves. Moreover, the controlling strategy, as a significant relevant factor affecting the efficiency of valves, will be discussed in this paper. At the end, the conclusion and worksof electric-pneumatic pressure proportional valves in the future will bediscussed to achieve the electrical integration. Full article
(This article belongs to the Special Issue Power Transmission and Control in Power and Vehicle Machineries)
Figures

Figure 1

Appl. Sci. EISSN 2076-3417 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top