Active Control of Fluid Pressure Pulsation in Hydraulic Pipe System by Bilateral-Overflow of Piezoelectric Direct-Drive Slide Valve

2014 ◽  
Vol 136 (3) ◽  
Author(s):  
Guan Changbin ◽  
Jiao Zongxia ◽  
Wu Shuai ◽  
Shang Yaoxing ◽  
Zheng Fanggang
Keyword(s):  
Active Control ◽  
High Speed ◽  
Pressure Pulsation ◽  
Control Method ◽  
Fluid Pressure ◽  
Slide Valve ◽  
Single Frequency ◽  
Direct Drive ◽  
Dual Frequency ◽  
Pipe System

In this paper, a novel active control of fluid pressure pulsation (ACFPP) is proposed, which meets the need of the high-pressure and high-speed hydraulic pipe system. A piezoelectric direct-drive slide valve (PDDSV) is designed and used as the active vibration absorber. Two ports of the PDDSV both connect to a bypass near the pump outlet and the other two ports both connect to the oil tank. By the bilateral-overflow through the shoulder of the PDDSV, the overflow wave generated in one cycle of spool motion can cancel two cycles of flow ripple. An adaptive-optimum control method based on the rotate-vector optimization method (RVOM) is adopted to adjust the control parameters in order to minimize the amplitude of the pressure pulsation. The biggest advantage of the proposed ACFPP is that it can eliminate the pressure pulsation when PDDSV only works at half of the pressure pulsation's frequency. The simulation and experimentation both verify the proposed ACFPP. By the proposed ACFPP, the suppression for the single-frequency component and dual-frequency components of the pressure pulsation have been both realized.

scholarly journals A Critical Review of Supersonic Flow Control for High-Speed Applications

2021 ◽  
Vol 11 (15) ◽  
pp. 6899
Author(s):  
Abdul Aabid ◽  
Sher Afghan Khan ◽  
Muneer Baig
Keyword(s):  
Supersonic Flow ◽  
Flow Control ◽  
Active Control ◽  
Critical Review ◽  
High Speed ◽  
Passive Control ◽  
Control Method ◽  
Sudden Expansion ◽  
Control Approach ◽  
Cost Efficient

In high-speed fluid dynamics, base pressure controls find many engineering applications, such as in the automobile and defense industries. Several studies have been reported on flow control with sudden expansion duct. Passive control was found to be more beneficial in the last four decades and is used in devices such as cavities, ribs, aerospikes, etc., but these need additional control mechanics and objects to control the flow. Therefore, in the last two decades, the active control method has been used via a microjet controller at the base region of the suddenly expanded duct of the convergent–divergent (CD) nozzle to control the flow, which was found to be a cost-efficient and energy-saving method. Hence, in this paper, a systemic literature review is conducted to investigate the research gap by reviewing the exhaustive work on the active control of high-speed aerodynamic flows from the nozzle as the major focus. Additionally, a basic idea about the nozzle and its configuration is discussed, and the passive control method for the control of flow, jet and noise are represented in order to investigate the existing contributions in supersonic speed applications. A critical review of the last two decades considering the challenges and limitations in this field is expressed. As a contribution, some major and minor gaps are introduced, and we plot the research trends in this field. As a result, this review can serve as guidance and an opportunity for scholars who want to use an active control approach via microjets for supersonic flow problems.

Dynamic Response of the Pipe Conveying Fluid with the Pressure Pulsation

2015 ◽  
Vol 1094 ◽  
pp. 491-494 ◽  
Author(s):  
Hong Bo Zhai ◽  
Jian Jun Su ◽  
Xiao Min Yan ◽  
Wei Liu
Keyword(s):  
Dynamic Response ◽  
Pressure Pulsation ◽  
Fluid Pressure ◽  
Response Characteristic ◽  
Pipe Conveying Fluid ◽  
Hydraulic Power ◽  
Working Pressure ◽  
Pipe System ◽  
Output Pressure ◽  
Conveying Fluid

The dynamic response characteristic of the pipe conveying fluid was researched with the fluid pressure pulsation in this article. For some hydraulic power pipe system, formed the mathematic models and the transfer matrices of the main hydraulic elements based on the fluid network algorithm, deduced the calculation formulae of input-output pressure pulsation, gained the transitive relationship of the fluid flow pulsation and pressure pulsation, and then studied the pressure pulsation amplitude of the hydraulic power pipes with different working pressures. This study, which analyzed the dynamic response of the pipe conveying fluid and discussed the feasibility of increasing the working pressure, is valuable for the design and the application of the pipes conveying fluid.

Hybrid vibro-acoustic active control method for vehicle interior sound quality under high-speed

2022 ◽  
Vol 186 ◽  
pp. 108419
Author(s):  
X.L. Wang ◽  
Y.C. Song ◽  
T.Z. Wang ◽  
Y.S. Wang ◽  
N.N. Liu
Keyword(s):  
Active Control ◽  
High Speed ◽  
Control Method ◽  
Sound Quality ◽  
Vehicle Interior ◽  
Active Control Method

Effect of Dual Frequency Ultrasound on the Bubble Formation in a Capillary Tube

2017 ◽  
Vol 139 (2) ◽  
Author(s):  
Benwei Fu ◽  
Nannan Zhao ◽  
Guoyou Wang ◽  
Hongbin Ma
Keyword(s):  
Bubble Growth ◽  
High Speed ◽  
Capillary Tube ◽  
Bubble Formation ◽  
Single Frequency ◽  
Quartz Tube ◽  
Outer Diameter ◽  
Dual Frequency ◽  
Heating Section ◽  
Frequency Ultrasound

A visual experimental investigation was conducted to determine the effect of dual frequency ultrasound on the bubble formation and growth in a capillary quartz tube. Two piezoelectric ceramics were used in this experiment. They were made of Pb-based lanthanum-doped zirconate titanates (PLZTs). The PLZTs were placed on a quartz tube with an inner diameter of 2 mm and an outer diameter of 3 mm. The capillary tube was vacuumed first and then charged with water using a filling ratio of 70%. The ultrasonic sound was applied to the heating section of a capillary tube. The bubble formation and growth were recorded by a high speed camera. As shown in figures, when the ultrasound with a single frequency of either 154 kHz or 474 kHz was applied, only one bubble was generated. When the dual frequencies of 154 kHz and 474 kHz were applied, more bubbles were generated. The speed of the bubble growth with dual frequency ultrasound was much higher than that with a single frequency. When a dual frequency ultrasound (154 kHz and 474 kHz) was used, the nucleation sites for bubble formation were significantly increased and the bubble growth rate enhanced.

Experiments in Active Stall Control of a Twin-Spool Turbofan Engine

2002 ◽  
Author(s):  
Dirk C. Leinhos ◽  
Stephen G. Scheidler ◽  
Leonhard Fottner ◽  
Frank Grauer ◽  
Jakob Hermann ◽  
...  
Keyword(s):  
Active Control ◽  
High Speed ◽  
Control Strategies ◽  
External Source ◽  
Rotating Stall ◽  
Operating Conditions ◽  
Air Injection ◽  
Rotor Speed ◽  
Direct Drive ◽  
Specific Operating Condition

The aerodynamic stability of aero engine compressors must be assured by active control systems in all operating conditions when the design surge margin is reduced in order to improve efficiency. While this has been investigated only on compressor rigs and single-spool engines in the past, this study focuses on the active control of the LARZAC 04 twin-spool turbofan. The objective is to demonstrate potential benefits, problems and solutions and also to provide a data base for numerical modeling and simulation of the capabilities of active control. Three different control strategies have been employed each of which refers to a specific operating condition and instability inception of the engine: The attenuation of disturbances travelling at rotor speed by modulated air injection into the LPC in the high speed range, the recovery of fully developed LPC stall at low speeds with a minimized amount of air and finally a constant air recirculation (HPC exit to LPC inlet) for stabilizing the compression system at different speeds based on the monitoring of a stability parameter. The injector is mounted upstream of the LPC and has ten circumferentially distributed nozzles for air injection into the tip region of the first rotor. The injected air which is either taken from an external source or from bleed air ports at the HPC exit is controlled by high-bandwidth direct-drive-valves. Disturbances travelling at rotor speed can be detected and attenuated with modulated air injection leading to a delay of stall onset. Fully developed rotating stall in the LPC was eliminated by asymmetric injection based on modal control strategies with less air than needed with constant air injection. By using online-stability-monitoring it is possible to initiate constant air recirculation when approaching the surge line, though the current design of the injector does not allow for large extension of the operating range for all spool speeds.

Digital Signal Processor Based Active Vibration Control System Using Adaptive Control Algorithm and Smart Actuators/Sensors

2001 ◽  
Author(s):  
P. Shashikala ◽  
V. Shankar ◽  
B. V. Nagaraja ◽  
R. Balasubramaniam ◽  
J. Harikrishnan
Keyword(s):  
System Identification ◽  
Active Control ◽  
High Speed ◽  
Control Method ◽  
Random Noise ◽  
Digital Signal ◽  
Lms Algorithm ◽  
Beam Structure ◽  
Line System ◽  
And Control

Abstract Adaptive feed forward control of structure based on ‘filtered -x’ LMS algorithm has been brought out for the active control of vibration in a typical CFRP beam structure. Initially the conventional filtered-x LMS control configuration and offline system identification method using DSP is discussed. Also the on-line system identification and control by additive random noise technique has been brought out. FIR filters are used for both system identification and control. Recent advances in electronics, high-speed digital signal processors have made active systems realizable, effective and inexpensive. Hence the active control method has been used to investigate a typical composite CFRP beam structure bonded externally with PZT actuators/sensors. At present vibration reduction of the order of 3db has been achieved.

Adaptive vibration active control of fluid pressure pulsations

2003 ◽  
Vol 217 (4) ◽  
pp. 311-318 ◽  
Author(s):  
Z Jiao ◽  
P Chen ◽  
Q Hua ◽  
S Wang
Keyword(s):  
Active Control ◽  
Power Supply ◽  
Control Method ◽  
Fluid Pressure ◽  
Fluid Power ◽  
Control Voltage ◽  
Pipeline System ◽  
Operation Conditions ◽  
Supply Systems ◽  
Orifice Valve

Conventionally, passive hydraulic absorbers are utilized in order to reduce the vibrations of the fluid power supply systems. It is very difficult to adapt the variable operation conditions, such as inconsistent vibration frequency and varying loads. This paper presents a new vibration active control method to diminish the vibrations of the fluid power supply efficiently. This method is adaptive and robust in controlling the fluctuating frequencies and load disturbances and is capable of keeping the vibrations at a minimum level under variable pump speeds. This paper illustrates the theory and experimentation of vibration active control of a fluid power supply pipeline system in detail. The multilayer piezoelectric technology (PZT) driven orifice valve is designed with characteristics of a proportional opening area to the control voltage, a high-frequency bandwidth and small size. The adaptive-optimum control method is adopted to adjust the control parameters at any instant against emerging disturbances. Based on the test rig, different vibration control methods were applied; the results indicate and confirm the validity of this principle.

The Radio Probe™: A New Measurement Tool for High Speed Integrated Circuits

2005 ◽  
Author(s):  
Mark Kimball
Keyword(s):  
Integrated Circuits ◽  
Integrated Circuit ◽  
High Speed ◽  
Attenuation Factor ◽  
Cost Effective ◽  
Frequency Measurement ◽  
Single Frequency ◽  
Measurement Tool ◽  
Probe Design ◽  
Differential Measurement

Abstract This article presents a novel tool designed to allow circuit node measurements in a radio frequency (RF) integrated circuit. The discussion covers RF circuit problems; provides details on the Radio Probe design, which achieves an input impedance of 50Kohms and an overall attenuation factor of 0 dB; and describes signal to noise issues in the output signal, along with their improvement techniques. This cost-effective solution incorporates features that make it well suited to the task of differential measurement of circuit nodes within an RF IC. The Radio Probe concept offers a number of advantages compared to active probes. It is a single frequency measurement tool, so it complements, rather than replaces, active probes.

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