Design Of Hydraulic System Research Articles

Reliability optimization design of hydraulic system considering oil contamination

This paper presents a reliability optimization design method for a hydraulic system that considers oil contamination. The proposed method applies the quantitative relationship between oil contamination and system reliability to the reliability design of a hydraulic system, while considering the performance, layout, and other design factors. A global reliability model of the hydraulic system is constructed based on the oil contamination control model. Further studies aiming at an optimization design model of the hydraulic system is established where the cost is the objective function, reliability index, size and structure range, performance requirements are constraints, structure size and oil change period are design variables. For illustration, a case study on the reliability optimization design of the oil supply point branch of the static pressure bracket of a certain type of heavy CNC horizontal lathe is considered.

Characterization of meso-scale mechanical properties of Longmaxi shale using grid microindentation experiments

Abstract Mechanical properties, such as the hardness H, Young’s modulus E, creep modulus C, and fracture toughness Kc, are essential parameters in the design of hydraulic fracturing systems for prospective shale gas formations. In this study, a practical methodology is presented for obtaining these properties through microindentation experiments combined with quantitative observations of the mineralogical phases using X-ray diffraction (XRD), scanning electron microscopy (SEM) with backscattered electron (BSE) imaging, and energy-dispersive X-ray spectroscopy (EDS) analyses. We apply this method in the case of three types of Longmaxi shales with different mineralogies (i.e. carbonate-, clay-, and quartz-rich, respectively), which allows us to determine the characteristic indentation depth, hc = 8–10 μm, beyond which the mechanical response of the carbonate-rich shale is homogeneous and independent of its complex heterogeneous microstructure. Moreover, exploiting the results of a large number of indentation tests, we demonstrate that the indentation modulus M of the shale increases as a power-law of hardness H, and its creep modulus C increases linearly with H. We also compute the fracture toughness Kc from the indentation data by assuming a perfectly plastic behavior of the sample. Our results are in good agreement with independent measurements of Kc determined by microscratch tests. Finally, further tests on quartz- and clay-rich samples of the Longmaxi shale suggest further variations in the samples’ mechanical properties depending on their burial conditions and the mechanical properties of their dominant mineral phases.

Dynamic optimization analysis of hydraulic pipeline system based on a developed response surface method

When designing a complex pipeline with long distance and multi-supports for offshore platform, it is necessary to analyze the vibration characteristics of the complex pipeline system to ensure that there is no harmful resonance in the working conditions. Therefore, the optimal layout of support is an effective method to reduce the vibration response of hydraulic pipeline system. In this paper, a developed dynamic optimization method for the complex pipeline is proposed to investigate the vibration characteristics of complex pipeline with multi-elastic supports. In this method, the Kriging response surface model between the support position and pipeline is established. The position of the clamp in the model is parameterized and the optimal solution of performance index is obtained by genetic algorithm. The number of clamps and the interval between clamps are considered as the constraints of layout optimization, and the optimization objective is the natural frequencies of pipeline. Taking a typical offshore pipeline as example to demonstrate the effectiveness of the proposed method, the results show that the vibration performance of the hydraulic pipeline system is distinctly improved by the optimization procedure, which can provide reasonable guidance for the design of complex hydraulic pipeline system.

Optimization on motion-robust and energy-saving controller for hydraulic penetration system of seabed equipment

Deep-sea Cone Penetration Test equipment (CPT) and In-Situ Sediment Acoustic Measurement System (ISSAMS) driven by hydraulic penetration system are the important equipment for in-situ detection of seabed sediment. The problems, such as poor position following precision and weak load disturbance rejection performance of the actuator in the hydraulic penetration system are common in the working process of deep-sea CPT and ISSAMS. In this paper, the self-developed deep-sea ISSAMS is taken as the example and various hydraulic penetration system models are established. Most importantly, an optimized control scheme, the fuzzy adaptive PID control scheme with pre-optimization based on genetic algorithm, is presented. To compare with the switch valve controlled hydraulic system used in the ISSAMS physical prototype, the PID control scheme and the fuzzy adaptive PID control scheme are designed as well. It shows that the proportional valve controlled hydraulic system has better position following precision and load disturbance rejection performance than the switch valve controlled hydraulic system and the pump controlled hydraulic system, with more than 95% improvement. The optimized control scheme will further improve the motion-robust performance. Besides, the energy conservation problem is discussed by comparing power requirement and energy consumption of different hydraulic system model and different control scheme. It shows that the pump controlled hydraulic system with the optimized control scheme is the most energy-efficient combination. This paper will have certain reference value to hydraulic penetration system design and motion controller design for deep-sea CPT and ISSAMS equipment.

Combined APSO-ANN and APSO-ANFIS models for prediction of pressure loss in air-water two-phase slug flow in a horizontal pipeline

Abstract Prediction of air-water two-phase flow frictional pressure loss in pressurized tunnels and pipelines is essentially in the design of proper hydraulic structures and pump systems. In the present study artificial neural networks (ANN) and adaptive neuro-fuzzy inference system (ANFIS) are employed to predict pressure loss in air-water two-phase slug flow. Adaptive particle swarm optimization (APSO) is also applied to optimize the results of the ANN and ANFIS models. To predict the pressure loss in two-phase flow, the frictional pressure loss coefficient needs to be determined with respect to the effective dimensionless parameters including two-phase flow Froude and Weber numbers and the air concentration. Laboratory test results are used to determine and validate the findings of this study. The performances of the ANN-APSO and ANFIS-APSO models are compared with those of the ANN and ANFIS models. Different comparison criteria are used to evaluate the performances of developed models, suggesting that all the models successfully determine the air-water two-phase slug flow pressure loss coefficient. However, the ANFIS-APSO performs better than other models. Good agreement is obtained between estimated and measured values, indicating that the APSO with a conjugated ANFIS model successfully estimates the air-water two-phase slug flow pressure loss coefficient as a complex hydraulic problem. Results suggest that the proposed models are more accurate compared to former empirical correlations in the literature.

Design and Calculation of Hydraulic Transmission System of Loader

In order to give full play to the power of the engine, it is necessary to find the operating point of the engine and the hydraulic torque converter working together. This paper designs the hydraulic shift system of ZL50 loader with advanced mechanism theory. Firstly, the hydraulic variable speed system of the loader is designed according to the speed and maximum traction of the loader. Then, by calculating the traction characteristics of the loader and the heating of the drive system and evaluating its performance, it provides a reliable theoretical basis for the overall design of the loader.

Rainfall Intensity-Duration-Frequency Relationship. Case Study: Depth-Duration Ratio in a Semi-Arid Zone in Mexico

Intensity–Duration–Frequency (IDF) curves describe the relationship between rainfall intensity, rainfall duration, and return period. They are commonly used in the design, planning and operation of hydrologic, hydraulic, and water resource systems. Considering the intense rainfall presence with flooding occurrences, limited data used to develop IDF curves, and importance to improve the IDF design for the Ensenada City in Baja California, this research study aims to investigate the use and combinations of pluviograph and daily records, to assess rain behavior around the city, and select a suitable method that provides the best results of IDF relationship, consequently updating the IDF relationship for the city for return periods of 10, 25, 50, and 100 years. The IDF relationship is determined through frequency analysis of rainfall observations. Also, annual maximum rainfall intensity for several duration and return periods has been analyzed according to the statistical distribution of Gumbel Extreme Value (GEV). Thus, Chen’s method was evaluated based on the depth-duration ratio (R) from the zone, and the development of the IDF relationship for the rain gauges stations was focused on estimating the most suitable (R) ratio; chosen from testing several methods and analyzing the rain in the region from California and Baja California. The determined values of the rain for one hour and return period of 2 years (P12) obtained were compared to the values of some cities in California and Baja California, with a range between 10 and 16.61 mm, and the values of the (R) ratio are in a range between 0.35 and 0.44; this range is close to the (R) ratio of 0.44 for one station in Tijuana, a city 100 km far from Ensenada. The values found here correspond to the rainfall characteristics of the zone; therefore, the method used in this study can be replicated to other semi-arid zones with the same rain characteristics. Finally, it is suggested that these results of the IDF relationship should be incorporated on the Norm of the State of Baja California as the recurrence update requires it upon recommendation. This study is the starting point to other studies that imply the calculation of a peak flow and evaluation of hydraulic structures as an input to help improve flood resilience in the city of Ensenada.

Design and energy utilization of electro-hydrostatic hydraulic hybrid system for battery bus

In order to solve the problems of large peak torque and short battery life when the city battery bus starts or accelerates, a new electro-hydrostatic hydraulic hybrid powertrain is designed in this paper that can operate efficiently in all speed conditions with a certain type of electric bus running in Chengdu. The improvement of comprehensive energy efficiency of power system by switching between different power modes under typical operating conditions is studied. Through the co-simulation of AMESim and MATLAB/Simulink-stateflow software, the vehicle and control models are established and the rule-based dynamic optimal energy management strategy is set. The dynamic performance and energy utilization characteristics of New European Driving Cycle and the cycle condition of investigation under actual driving environments are analyzed. The core problems of energy coupling of electro-hydrostatic hydraulic hybrid powertrain are studied experimentally to verify the correctness of the design thought and simulation model. The results show that under the premise of satisfying the dynamic performance, the designed electro-hydrostatic hydraulic hybrid system can effectively improve the overall average efficiency of operating point of the electric motor and greatly reduce the peak torque. The peak torque is reduced by 36.4% and the battery power consumed by the selected cycle is reduced by 33.98% under New European Driving Cycle conditions. Under the actual cycle conditions, the peak torque is reduced by 28.9%, and the battery power consumed by the selected cycle is reduced by 32.3%.

Transient behavior of two-stage load rejection for multiple units system in pumped storage plants

Pumped storage plants (PSPs) are being rapidly deployed and developed since they are cost-effective and mature energy storage solutions to the penetration of renewable energy sources (RES). Hydraulic transient analysis on PSPs, especially under extreme operating conditions such as two-stage load rejection (LR), is the key to safe hydraulic system design. Two-stage LR, involving a step-wise reduction in load, may induce extremely low draft tube pressure (DTP), directly threatening the safety of a multiple units PSP. Using numerical simulation, this study systematically investigates the behavior of the hydraulic parameters, and reveals the mechanism leading to the extremely low DTP during a two-stage LR process. The results indicate that the asynchronously varying discharge, coming from the inconsistent instants of time rejecting load and subsequent pressure difference, is the origin of severe reverse water hammer. Furthermore, the rate of discharge change of the subsequent load rejection turbine (SLRT) is confirmed to be the critical factor. The unexpected low DTP occurs exactly when its rate of discharge change reaches its minimum value. Additionally, the deeper the moving trajectory of the SLRT enters the reverse pump zone, the more severe the low DTP will be. Finally, two engineering measures that can economically and effectively improve the minimum DTP are proposed based on the hydraulic behavior of two-stage LR.

Research on Large-diameter Electro-hydraulic Rotary Table and Its Control System for Deep-water Drilling Rig

With the rapid development of offshore oil and gas drilling equipment industry, it is imperative to study the technology of large-diameter electrically controlled hydraulic rotary table for deep-water drilling rig. Firstly, the hydraulic rotary table design is carried out, which include mechanical structure, electronic control system and hydraulic system design. Secondly, studying the electric control system. The driving force of the electric hydraulic rotary table comes from the hydraulic system, and its control function is mainly realized by the electric control system. This paper analyzes the input and output of the the hydraulic rotary table’s electric control system, completes the design of the hardware system and software system, and puts forward an electric control system scheme of the hydraulic rotary table with perfect function and reasonable configuration. Finally, the conclusion is drawn that the hydraulic rotary table, which is driven by hydraulic motor and rotates at low speed, has the characteristics of compact structure, light weight and large opening size, and can meet the requirement of laying down the riser. It is of great significance to the development of deepwater offshore drilling equipment.

Development and Application of the special drilling rig for oblique guide hole

For the construction conditions of long-distance inclined drilling in roadway or chamber, a new type of self-moving hydraulic top-drive drilling rig is developed independently. Follow the research steps of the overall design, the key-parts design, the hydraulic system design, the industrial test. The main functional organization of the oblique-guide-hole drilling machine includes the power head, the feeding device, the power source, the drill pipe delivery installation, the rig control system, the hydraulic transmission system. The special oblique-guide-hole drilling rig realizes the construction requirement of any inclined drilling of 0∼90°, at the same time, it can meet the technical requirements of the directional drilling assembly, that is the combination of down-hole motor, non-magnetic drill collar and Wireless while drilling. The track of long-distance oblique drilling is precisely controlled. The field test of the special oblique-guide-hole drilling rig is at Changlongshan Pumped Storage Power Station in Zhejiang, China. The actual guide hole has an inclined length of 289.5m, and the deviation slope of the borehole is controlled within 2.86‰. It is successfully completed the anti-shaft guide hole in the lower section of the 1# diversion system high-pressure pipeline safely, quickly, and efficiently.

Design of Remote Hydraulic Teaching System

In this paper, a set of remote hydraulic teaching experiment system is designed and developed based on the demand of teaching experiment of hydraulic related courses in colleges and universities, which can enable teachers or students to conduct experiment operation on the field hydraulic testing platform at the remote client, so as to facilitate teachers and students to carry out hydraulic teaching experiment and research. The main contents of this paper are as follows: according to the requirements of hydraulic servo control system related to the teaching experiment, the experimental project of remote hydraulic teaching experiment system is determined. Through the analysis and comparison of C/S and B/S software system architectures, the remote monitoring scheme based on B/S mode is determined. Completed the design of the hydraulic circuit of the hydraulic test bench, developed the field measurement and control system based on LabVIEW, and built the remote monitoring system based on B/S mode. The development of the remote hydraulic teaching experiment system was completed. The input signal response experiment and load characteristic experiment of the valve-controlled motor electro-hydraulic speed servo control system were carried out on the remote client to the field hydraulic experiment platform, and the experimental results were analyzed. The experimental process and results have reached the expected target and meet the demand of remote hydraulic experiment.

Design and Research of Energy-saving Hydraulic System for Walking Beam Furnace

Design and Research of Energy-saving Hydraulic System for Walking Beam Furnace

Modeling and Experimental Evaluation of a Variable Hydraulic Transmission

A low-loss hydraulic transmission offers an efficient and lightweight means to route power from a central source to distal actuators, with example applications in legged and wearable robots. For example, one could develop a completely passive hydraulic transmission for an exoskeleton that routes power from a healthy limb to a limb weakened by neurological injury to enable self-assist or rehabilitation. In this article, we introduce and model a variable hydraulic transmission that features rolling diaphragm cylinders and a discretely variable transmission ratio. The variable transmission utilizes digital hydraulics, wherein valves switch redundantly mounted cylinders in and out of the hydraulic circuit. The article discusses the impact of configuration on the available transmission ratios and passivity. Our modeling efforts focus on the parasitic effects that arise with power losses between the driving and driven joints, compliance and energy storage in the transmission, and drift during switching. We carefully validate the model, comparing analytically predicted fine and gross behaviors to experimental observations. Experimental results demonstrate the feasibility and utility of the proposed device and the associated model which serves as an important tool for the design and control of digital hydraulic transmission systems.

A Deep Reinforcement Learning Approach for Global Routing

Abstract Global routing has been a historically challenging problem in the electronic circuit design, where the challenge is to connect a large and arbitrary number of circuit components with wires without violating the design rules for the printed circuit boards or integrated circuits. Similar routing problems also exist in the design of complex hydraulic systems, pipe systems, and logistic networks. Existing solutions typically consist of greedy algorithms and hard-coded heuristics. As such, existing approaches suffer from a lack of model flexibility and usually fail to solve sub-problems conjointly. As an alternative approach, this work presents a deep reinforcement learning method for solving the global routing problem in a simulated environment. At the heart of the proposed method is deep reinforcement learning that enables an agent to produce a policy for routing based on the variety of problems, and it is presented with leveraging the conjoint optimization mechanism of deep reinforcement learning. Conjoint optimization mechanism is explained and demonstrated in detail; the best network structure and the parameters of the learned model are explored. Based on the fine-tuned model, routing solutions and rewards are presented and analyzed. The results indicate that the approach can outperform the benchmark method of a sequential A* method, suggesting a promising potential for deep reinforcement learning for global routing and other routing or path planning problems in general. Another major contribution of this work is the development of a global routing problem sets generator with the ability to generate parameterized global routing problem sets with different size and constraints, enabling evaluation of different routing algorithms and the generation of training datasets for future data-driven routing approaches.

Design methodology to optimise induction machines based stand‐alone electrical wind water pumping systems

A novel methodology for designing a wind-electric water pumping system is developed in this study. The system employs a self-excited induction generator (SEIG) driven by a wind turbine (WT) and an induction motor (IM) feeding a water pump. Selection of values and proper configuration of excitation capacitors for this system is the key factor which is performed by an optimisation algorithm. The methodology commences with the design of hydraulic system and choice of proper pump. Then, the gearbox ratio of the chosen WT is determined to coordinate the characteristic of the WT with that of the pump. The aim is operation of the system near the maximum power output of the WT in different wind speeds. Thereafter, the electrical system is designed by choosing the suitably rated powers for the SEIG and IM. The optimal capacitor values in various configurations, viz. the shunt, short shunt, long shunt, T, and Π, are calculated utilising the genetic algorithm and then, the best configuration considering the system operating conditions is introduced. The objective function is defined to regulate the IM operating point at the knee point of its magnetising characteristic under wind speed variations. The system performance is evaluated through simulation and experiment.

Software Environment for Computer-Aided Heuristic Optimization of Hydraulic Systems for Synchronous Movement of Actuators of Various Functional Purposes

A software environment was developed for computer-aided design of optimal throttle hydraulic synchronization systems of actuators of various functional purposes operating under conditions of external alternating-sign force effects. The criterion of an optimization procedure was the minimization of a mismatch time of relative movement of actuators during operation. A compute core of an object-oriented code was constructed on the basis of a dynamic mathematical model of a synchronization system consisting of four power cylinders. A model problem was solved with the help of the created software environment. This model problem demonstrated the efficiency of the proposed multidimensional optimization process. The methodology was based on the use of the well-known heuristic method (binary coded genetic algorithm) and the subsequent improvement (in the sense of a given objective functional) of the obtained solution by a method on the basis of the Hooke-Jeeves algorithm. Recommendations on the practical application of the software and mathematical support for achieving the best convergence to the extreme value of a vector of controlled parameters were formulated.

Simulation of Hydraulic System Faults for Marine Machinery Based on AMESim

Zhou, W., 2019. Simulation of hydraulic system faults for marine machinery based on AMESim. In: Gong, D.; Zhu, H., and Liu, R. (eds.), Selected Topics in Coastal Research: Engineering, Industry, Economy, and Sustainable Development. Journal of Coastal Research, Special Issue No. 94, pp. 357–361. Coconut Creek (Florida), ISSN 0749-0208.With the rapid development of marine ship manufacturing, engineering machinery has become more complex, continuous and automated. It has become the focus of current research to effectively detect the hydraulic system of marine machinery using the modern scientific methods. For this, the Advanced Modelling Environment for Simulation of Engineering Systems (AMESim) was adopted in this study. By fully explaining the model of the basic hydraulic components and the parameter selection of the overall modelling for the marine machinery hydraulic system, this paper achieves the simulation design of the marine machinery hydraulic system based on the AMESim integrated platform. The comparison between the AMESim-based simulation results and the mathematical model verifies the rationality of the AMESim-based simulation for the marine machinery hydraulic system; meanwhile, compared with the simulation results based on MATLAB, the AMESim-based simulation shows good superiority, which is of great guiding significance for shipbuilding projects.

Numerical hydrodynamic researches for justifying design of the Nizhny Novgorod low-head hydraulic system

Introduction. A problem area of the Volga river between the Nizhny Novgorod hydroelectric power station and the city of Nizhny Novgorod has been surveyed, where unfavourable conditions for navigation, power generation, and safe living in the downstream are formed as a result of the landing level. The only solution to the problem is construction of a low-head hydraulic system (NNGU) that will reduce intensity of relief re-formations in the downstream of the Nizhny Novgorod hydraulic system and stop lowering of the bottom and level marks in this area. Purpose of this research is to study processes that occur upstream and downstream from the site of the facility to identify hazardous trends and develop practical solutions to minimize negative impacts; as well as a review of mathematical models conducted in this area for improving navigation conditions. Materials and methods. Materials of previous researches on this subject, pre-design engineering surveys and layout drawings of the designed hydraulic system are used. The researches have been performed with numerical methods using Stream 2D software package that is based on the two-dimensional differential equation Saint-Venant system. Options for low-flow conditions are considered, taking into account passing of the Nizhny Novgorod hydroelectric power station, as well as rare floods. Results. Plans for distribution of velocity modules and vectors are created, which show that construction of the low-pressure hydraulic system results in decrease in slopes and velocities of water in the problem area of the Volga-Kama cascade, as a result of which intensity of bottom deformations decreases. Rare flow passage demonstrated that difference in pools is insignificant, while, at the same time, flow of water along the left-bank floodplain passes more than believed before. Calculations of low-flow conditions demonstrated a number of deficiencies in the design, which are associated with insufficient throughput and uneven distribution of flow rates in the discharge area of the waterfront. Conclusion The results demonstrated a practical importance of using mathematical simulation with numerical methods in a two-dimensional formulation, which allow us to consider processes in more detailed manner and change the hydraulic system design in a timely manner.

Multi-objective optimization in the vibration characteristics of a hydraulic steering system using a conservative and feasible response surface method

ABSTRACTThis article addresses the approximate multi-objective optimum design of an automotive hydraulic steering system based on a multi-body dynamics analysis. The design problem of a hydraulic steering system was formulated to determine the design dimensions of a steering mechanism that is able to estimate the multi-objective Pareto-optimal solutions of weight and vibration frequencies that are subject to the dynamic response constraints of the main steering components. The multi-objective Pareto-optimal solutions were calculated using the non-dominated sorting genetic algorithm-II (NSGA-II) based on various approximate models, and reviewed in terms of exploration performance and constraint feasibility. The multi-objective Pareto-optimal solution characteristics according to the approximate model were reviewed to identify a proper approximate model for the engineering design of a hydraulic steering system. The results of the Pareto solution from the proposed optimization methods could improve the vibration performance as well as the weight reduction of hydraulic steering systems.