Adaptive Control of a Piezoelectric Valve for Fluid-Borne Noise Reduction in a Hydraulic Buck Converter

The hydraulic buck converter (HBC) is a novel high-bandwidth and energy-efficient device which can adjust or control flow and pressure by a means that does not rely on throttling the flow and dissipation of power. However, the nature of a HBC can cause severe fluid-borne noise (FBN), which is the unsteady pressure or flow in the fluid-filled hydraulic circuit. This is due to the operation nature of a high-speed switching valve of the device. The FBN creates fluctuating forces on the pipes which lead to system structure-borne noise that develops air-borne noise reaching to 85 dB. Thus, there is a need for an effective method that does not impair the system performance and efficiency to reduce the FBN. This paper describes the first investigation of an active controller for FBN cancellation in a HBC based on in-series and by-pass structures. The dynamics and the noise problem of the HBC are investigated using the analytical models. A piezoelectrically actuated hydraulic valve with a fast response and high force is applied as the adaptive FBN attenuator. The performance and robustness of the designed noise controller were studied with different operating conditions of a HBC. Simulated and experimental results show that excellent noise cancellation (30 dB) was achieved. The proposed active attenuator is a very promising solution for FBN attenuation in modern digital hydraulic systems which promise high energy efficiency but suffer severe noise or vibration problems in practice.

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Theoretical and Experimental Studies of a Digital Flow Booster Operating at High Pressures and Flow Rates

Processes ◽

10.3390/pr8020211 ◽

2020 ◽

Vol 8 (2) ◽

pp. 211 ◽

Cited By ~ 1

Author(s):

Chenggang Yuan ◽

Vinrea Lim Mao Lung ◽

Andrew Plummer ◽

Min Pan

Keyword(s):

Energy Efficiency ◽

High Pressure ◽

Flow Rate ◽

High Energy ◽

Control Flow ◽

Fluid Power ◽

Analytical Models ◽

Operating Pressure ◽

Hydraulic Systems ◽

Flow Rates

The switched inertance hydraulic converter (SIHC) is a new technology providing an alternative to conventional proportional or servo-valve-controlled systems in the area of fluid power. SIHCs can adjust or control flow and pressure by means of using digital control signals that do not rely on throttling the flow and dissipation of power, and provide hydraulic systems with high-energy efficiency, flexible control, and insensitivity to contamination. In this article, the analytical models of an SIHC in a three-port flow-booster configuration were used and validated at high operating pressure, with the low- and high-pressure supplies of 30 and 90 bar and a high delivery flow rate of 21 L/min. The system dynamics, flow responses, and power consumption were investigated and theoretically and experimentally validated. Results were compared to previous results achieved using low operating pressures, where low- and high-pressure supplies were 20 and 30 bar, and the delivery flow rate was 7 L/min. We concluded that the analytical models could effectively predict SIHC performance, and higher operating pressures and flow rates could result in system uncertainties that need to be understood well. As high operating pressure or flow rate is a common requirement in hydraulic systems, this constitutes an important contribution to the development of newly switched inertance hydraulic converters and the improvement of fluid-power energy efficiency.

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Theoretical and Experimental Studies of a Switched Inertance Hydraulic System in a Four-Port High-Speed Switching Valve Configuration

10.20944/preprints201704.0177.v1 ◽

2017 ◽

Author(s):

Min Pan ◽

Andrew Plummer ◽

Abdullah El Agha

Keyword(s):

Hydraulic System ◽

High Speed ◽

Experimental Studies ◽

Control Flow ◽

Analytical Models ◽

Switching Valve ◽

Direction Control ◽

High Bandwidth ◽

And Performance ◽

High Speed Switching

The switched inertance hydraulic system (SIHS) is a novel high-bandwidth and energy-efficient digital device which can adjust or control flow and pressure by a means that does not rely on throttling the flow and dissipation of power. An SIHS can provide an efficient step-up or step-down of pressure or flow rate by using a digital control signal. In this article, analytical models of an SIHS in a four-port high-speed switching valve configuration are proposed, and the system dynamics and performance are investigated theoretically and experimentally. The flow responses, system characteristics and power consumption can be predicted effectively and accurately by using the proposed models, which were validated by comparing with experiments and with numerical simulation. The four-port configuration is compared with the three-port configuration, and it is concluded that the former one is less efficient for valves of the same size, but provides a bi-direction control capability. As bi-direction control is a common requirement, this constitutes an important contribution to the development of efficient digital hydraulics.

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Effect on Heat Transfer of Particle Migration in Suspensions of Nanoparticles Flowing Through Minichannels

ASME 2nd International Conference on Microchannels and Minichannels ◽

10.1115/icmm2004-2434 ◽

2004 ◽

Cited By ~ 6

Author(s):

Dongsheng Wen ◽

Yulong Ding

Keyword(s):

Heat Transfer ◽

High Speed ◽

High Performance ◽

High Energy ◽

Constant Heat Flux ◽

Operating Conditions ◽

Particle Migration ◽

Wall Region ◽

Self Diffusion ◽

Small Channels

Thermal management is one of the greatest challenges in maintaining the functionality and reliability of high-speed micro-electronic systems such as MEMS and NEMS. This requires development of high performance heat transfer media, which can not only flow through micro- and nano-channels under local operating conditions, but also carry as more heat as possible out of the system. Recent work has shown that suspensions of nanoparticles with a size considerably smaller that 100nm but with thermal conductivity orders of magnitudes higher that the base liquids have a greater potential as a high energy carrier for the micro- and nano-systems. However, it is also known that particles in a suspension undergoing a shearing action may migrate, hence lead to non-uniformity. This indicates that the efficiency of heat transfer in the micro- and nano-channels may not be as superior as expected, which bears significance to the system design and operation. This work aims at addressing this issue by examine the effect of particle migration on heat transfer in small channels. This involves development of both flow and heat transfer models, and numerical solution to the models. The flow model takes into account the effects of the shear-induced and viscosity gradient-induced particle migrations, as well as self-diffusion due to the Brownian motion, which is coupled with an energy equation. The results show that particle migration leads to concentration of particles in the wall region can be much lower than that in the core region. Particle migration is also shown to increase the Nusselt number under both constant temperature and constant heat flux conditions.

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Experimental and Numerical Investigation of the Unsteady Flow Field in a Vaned Diffuser of a High-Speed Centrifugal Compressor

Journal of Turbomachinery ◽

10.1115/1.4029175 ◽

2015 ◽

Vol 137 (7) ◽

Cited By ~ 4

Author(s):

Klemens Vogel ◽

Reza S. Abhari ◽

Armin Zemp

Keyword(s):

Centrifugal Compressor ◽

High Speed ◽

Pressure Fluctuations ◽

Leading Edge ◽

Fast Response ◽

Operating Conditions ◽

Wake Flow ◽

Vaned Diffuser ◽

Wide Range ◽

The Impact

Vaned diffusers in centrifugal compressor stages are used to achieve higher stage pressure ratios, higher stage efficiencies, and more compact designs. The interaction of the stationary diffuser with the impeller can lead to resonant vibration with potentially devastating effects. This paper presents unsteady diffuser vane surface pressure measurements using in-house developed, flush mounted, fast response piezoresistive pressure transducers. The unsteady pressures were recorded for nine operating conditions, covering a wide range of the compressor map. Experimental work was complemented by 3D unsteady computational fluid dynamics (CFD) simulations using ansys cfx V12.1 to detail the unsteady diffuser aerodynamics. Pressure fluctuations of up to 34.4% of the inlet pressure were found. High pressure variations are present all along the vane and are not restricted to the leading edge region. Frequency analysis of the measured vane surface pressures show that reduced impeller loading, and the corresponding reduction of tip leakage fluid changes the characteristics of the fluctuations from a main blade count to a total blade count. The unsteady pressure fluctuations in the diffuser originate from three distinct locations. The impact of the jet-wake flow leaving the impeller results in high variation close to the leading edge. It was observed that CFD results overpredicted the amplitude of the pressure fluctuation on average by 62%.

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Design and performance analysis of hydraulic switching valve driven by magnetic shape memory alloy

Advances in Mechanical Engineering ◽

10.1177/16878140211016985 ◽

2021 ◽

Vol 13 (5) ◽

pp. 168781402110169

Author(s):

Hu Shi ◽

Zhaoying Liu ◽

Haitao Wang ◽

Xuesong Mei

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Simulation Analysis ◽

Dynamic Performance ◽

Fast Response ◽

Operating Conditions ◽

Step Response ◽

Magnetic Shape Memory ◽

Switching Valve ◽

Magnetic Shape Memory Alloy

In this paper, the hydraulic switching valve is designed and its dynamic performance is investigated through proposing a fast response actuator with magnetic shape memory alloy (MSMA) to drive the valve. MSMA actuator with spring return is designed and a double-layered coil is constructed to achieve compactness of electromagnetic case. The dynamic characteristics of the MSMA actuator are analyzed and the step response characteristics is tested. Hydraulic switching valve with MSMA actuator is designed with poppet type. Pressure and velocity field in the flow channel under different valve opening and different inlet and outlet pressure differences are analyzed in COMSOL Multiphysics software. The dynamics of the valve poppet during opening and closing process is modeled mathematically, and simulation analysis are conducted in AMESim software to analyze the response of valve under step and square wave signals. The step response of output flow rate and pressure-flow characteristic under different operating conditions are obtained through experiment. The results show that the MSMA based valve can achieve fast response with opening time of 5 ms at the pressure difference of 1 MPa, providing a theoretical support for the development of hydraulic switching valve with high performance actuator driven by MSMA.

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Experimental and Numerical Investigation of the Unsteady Flow Field in a Vaned Diffuser of a High-Speed Centrifugal Compressor

Volume 2D: Turbomachinery ◽

10.1115/gt2014-25862 ◽

2014 ◽

Cited By ~ 2

Author(s):

Klemens Vogel ◽

Reza S. Abhari ◽

Armin Zemp

Keyword(s):

Centrifugal Compressor ◽

High Speed ◽

Pressure Fluctuations ◽

Leading Edge ◽

Fast Response ◽

Operating Conditions ◽

Wake Flow ◽

Vaned Diffuser ◽

Wide Range ◽

The Impact

Vaned diffusers in centrifugal compressor stages are used to achieve higher stage pressure ratios, higher stage efficiencies and more compact designs. The interaction of the stationary diffuser with the impeller can lead to resonant vibration with potentially devastating effects. This paper presents unsteady diffuser vane surface pressure measurements using in-house developed, flush mounted, fast response piezo-resistive pressure transducers. The unsteady pressures were recorded for 9 operating conditions, covering a wide range of the compressor map. Experimental work was complemented by 3D unsteady CFD simulations using ANSYS CFX V12.1 to detail the unsteady diffuser aerodynamics. Pressure fluctuations of up to 34.4% of the inlet pressure were found. High pressure variations are present all along the vane and are not restricted to the leading edge region. Frequency analysis of the measured vane surface pressures show that reduced impeller loading and the corresponding reduction of tip leakage fluid changes the characteristics of the fluctuations from a main blade count to a total blade count. The unsteady pressure fluctuations in the diffuser originate from three distinct locations. The impact of the jet wake flow leaving the impeller results in high variation close to the leading edge. It was observed that CFD results overpredicted the amplitude of the pressure fluctuation on average by 62%.

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Design and Analyze of Optical System for High-Speed Three-Channel Framing Camera

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.433-435.873 ◽

2013 ◽

Vol 433-435 ◽

pp. 873-876

Author(s):

Chun Yu Liu ◽

Tuo Qi Xu ◽

Zhen Xu

Keyword(s):

Electron Beam ◽

Optical System ◽

High Speed ◽

Focal Length ◽

Fast Response ◽

High Energy ◽

Time Resolved ◽

Beam Parameters ◽

Image Planes ◽

Framing Camera

High-speed multi-frame camera has been widely used for time-resolved measurement of electron beam parameters (especially for high energy and high current beam) for its fast response and high resolution. According to the requirements of a electron beam observation experiment, a three-channel framing camera optical system is designed. The system has 300mm focal length, 2.5 F#, 200lp/mm resolution. To validate the design results, visual microscope and magnify methods are used to test the consistency of image quality of three image planes. Test results show that the system fully meet the design requirements.

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A Parallel CFD Tool to Produce Faulty Blade Signatures for Diagnostic Purposes

Volume 5: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education ◽

10.1115/98-gt-169 ◽

1998 ◽

Author(s):

D. G. Koubogiannis ◽

V. P. Iliadis ◽

K. C. Giannakoglou

Keyword(s):

High Speed ◽

Unstructured Grids ◽

Fast Response ◽

Operating Conditions ◽

Pressure Measurements ◽

Diagnostic Systems ◽

Compressor Cascade ◽

Computational Fluid Dynamics Cfd ◽

Response Pressure ◽

The One

In the turbomachinery field, many diagnostic systems utilize databases with symptoms corresponding to the most frequent operation faults. Thanks to Computational Fluid Dynamics (CFD), databases can be created without costly experiments, whereas the use of unstructured grids in combination with parallel processing makes the whole task easy and fast to accomplish. In this paper, a procedure that builds up a database for gas-turbine fault diagnosis is demonstrated. Advanced CFD tools that operate concurrently on multi-processor platforms are used. The so-prepared database contributes to the identification of faults through the analysis of the unsteady pressure signals that correspond to hypothetical sensors located in the inter-blade region. The pressure signals are post-processed in a similar way to the one experimentalists employ for fast-response pressure measurements. Symptoms related to displaced and/or twisted blades in an industrial high-speed compressor cascade, at design and off-design operating conditions, are analyzed.

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Efficient Control of a Switched Inertance Hydraulic Converter With a Time-Varying Load

10.1115/fpmc2021-68832 ◽

2021 ◽

Author(s):

Chenggang Yuan ◽

Andrew Plummer ◽

Min Pan

Keyword(s):

High Efficiency ◽

High Energy ◽

Pi Controller ◽

Control Flow ◽

Switching Frequency ◽

Time Varying ◽

Hydraulic Systems ◽

Controlled Systems ◽

Loading Effects ◽

And Control

Abstract Switched inertance hydraulic converters (SIHC) are new digital hydraulic devices which provide an alternative to conventional proportional or servo valve-controlled systems in hydraulic fluid power. SIHCs can adjust and control flow and pressure by means of using digital control signals that do not rely on throttling the flow and dissipation of power, and provide hydraulic systems with high-energy efficiency, good controllability, and insensitivity to contamination. A flow booster is one configuration of SIHCs which can deliver more flow than the supply flow. In this article, the loading effects of SIHCs are investigated by applying a time-varying load on the flow booster. A control system consisting of a PI controller and a switching frequency optimizer was designed to operate a flow booster at its optimal switching frequencies and switching ratios to maximize system efficiency when the load varies. Simulated results showed that the flow booster with the proposed controller has very good dynamic response and can be operated at an average efficiency of 70% with a time-varying load. Compared with only using a PI controller, the proposed controller can improve the overall efficiency by up to 20%. As time-varying loading conditions are commonly found in hydraulic applications, this work constitutes an important contribution to the design and development of high-efficiency SIHCs.

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