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This paper reports an improvement of the particle-excitation flow control valve. The valve that we have designed in previous reports can control air flow, using particle excitation by piezoelectric resonance, and has the following advantages: small size, lightweight, high response and continuous airflow control. However, in our previous models, the relationship between the driving voltage and the flow quantity was nonlinear. In this report, we improved the valve to realize proportional flow control. The valve consists of the orifice plate, that has some orifices, and steel particles to seal the orifices and piezoelectric transducer. It controls air flow by the voltage applied to the transducer. For proportional flow control, it is important to adjust the orifice position adequately. In this report, we optimized the orifice position, considering resonance condition of the valve. We designed the experimental prototype using a bolt-clamped Langevin type transducer and decided orifice position. And we evaluated its vibration properties and flow-rate characteristics. The experimental results showed that our designed prototype can proportionally control airflow.

In order to design high-strength downhole flow control valve, realize stratified oil and gas production and dynamic regulation, improve mining efficiency, reduce pollution and promote the development of intelligent completion technology, this paper selects processing materials suitable for electro-hydraulic composite intelligent completion flow control valve based on field working conditions and the working principle of hydraulic control flow control valve. The structure of key components such as valve body, slide sleeve and throttle valve sleeve is designed, and the mechanical properties of key components of flow control valve are modeled and simulated successively by numerical simulation method combined with the actual service conditions of flow control valve in the underground, and the service reliability of flow control valve is clarified. The results show that: Under the coupling conditions of pressure 50 MPa, load 650 KN and temperature 125 °C, the maximum stress value appears on the surface of the throttle valve sleeve is 980 MPa, and the maximum deformation of the parts is controlled within 0.202 mm, and the strength of all parts is lower than the yield strength of the material, fully meeting the requirements of the field working conditions. This tool is of great significance for improving oil field recovery and intelligent well completion development.

With the development of micro-satellite propulsion system towards high precision, light and miniaturization, higher requirements are put forward for precise adjustment of propulsion system. Based on the principle of piezoelectric micro-displacement drive, this paper designs a light and small proportional flow control valve, adopts compliant amplification mechanism, develops the throttling design of small flow in the form of valve needle, analyzes the flow characteristics in the proportional adjustment process under different parameters, and realizes the micro-flow control ability with a flow control range of 0∼2mg/s and a flow control accuracy better than 3%. This design and analysis method can meet the needs of large-scale and high-precision flow control, and provide technical support for subsequent engineering applications.

The cable controlled intelligent separate injection process realizes the continuous monitoring and real-time measurement and adjustment of downhole parameters, greatly improves the measurement and adjustment efficiency, provides sufficient data for reservoir analysis, and helps to tap the potential of remaining oil in the later stage of ultra-high water cut. However, due to the multi-disciplinary application of downhole tools and complex process, it is found in the previous field test that The number of wells with more than two years of operation of cable controlled intelligent separate injection wells accounts for only 51.9%, which can not meet the needs of large-scale application. Through the fault analysis of the early test well, the key factors affecting the success rate of well completion are found. Aiming at the main problems, the flow control valve of the cable controlled intelligent water distributor, the cable sealing connection process and the well flushing valve structure through the cable packer are optimized and improved. The flow control valve of cable controlled intelligent water distributor is opened and closed smoothly under 10MPa pressure difference, and the leakage is less than 1m³/d; The connection between the cable and the cable controlled intelligent water distributor is sealed reliably, and the cable can pass through the upper and lower joints of the cable packer smoothly; Since the optimization of process technology until January 2023, 223 wells have been tested on site, and the number of wells with more than two years of operation has increased from 56.1% to 91.9%. The stability of the optimized cable controlled intelligent separate injection process has been improved, which lays a foundation for the large-scale application of this technology in the oilfield.

FMEA is a widely used tool for decades and is also used as an industrial standard. However, there are two main drawbacks of this analysis that have been specified from the beginning. The first one is risk prioritization, which is expressed by a risk priority number (RPN). The RPN is a product of three factors with equal weight: severity (S), occurrence (O), and detection (D), which may produce equal risk priority for different combinations of S, O, and D. The second is the uncertainties caused by converting linguistic terms into quantitative data. The essential data used in the FMEA strongly depend on subjective experts’ opinions, knowledge, and experience. For decades, various attempts of overcoming these weaknesses have been made, not only by academics but also by industry. The Automotive Industry Action Group (AIAG) and Verband der Automobilindustrie (VDA) have created an FMEA handbook that defines action priority (AP) depending on the combination of severity, occurrence, and detection numbers. This study presents an alternative to risk prioritization in FMEA based on failures of the tasks which analyzed systems perform. The fundamental factors S, O, and D have been redefined in a way to minimize uncertainties. The proposed method has been implemented in the flow control valve and can be easily applied in mechanical engineering applications.

Due to the requirements of the working environment, the marine axial flow control valve needs to reduce the noise as much as possible while ensuring the flow capacity to meet the requirements. To improve the noise reduction effect of the axial flow control valve, this paper proposes a Stacking integrated learning combined with particle swarm optimization (PSO) method to optimize a multi-stage step-down sleeve of the axial flow control valve. The liquid dynamic noise and flow value of the axial flow control valve are predicted by computational fluid dynamics. Based on the preliminary evaluation of its performance, the structural parameters of the multi-stage pressure-reducing sleeve are parameterized by three-dimensional modeling software. The range of design variables is constrained to form the design space, and the design space is sampled by the optimal Latin hypercube method to form the sample space. An automated solution platform is built to solve noise and flow values under different structural parameters. The Stacking method is used to fuse the three base learners of decision tree regression, Kriging, and support vector regression to obtain a structural optimization fusion model with better prediction accuracy, and the accuracy of the fusion model is evaluated by three different error metrics of coefficient of determination ( R 2 ), Root Mean Squared Error, and Mean Absolute Error. Then the PSO particle swarm optimization algorithm is used to optimize the fusion model to obtain the optimal structural parameter combination. The optimized multi-stage depressurization structure parameters are as follows: hole diameter t 1  = 3.8 mm, hole spacing t 2  = 1 mm, hole drawing angle t 3  = 6.4°, hole depth t 4  = 3.4 mm, and two-layer throttling sleeve spacing t 5  = 4 mm. The results show that the peak sound pressure level of the noise before and after optimization is 91.32 dB(A) and 78.2 dB(A), respectively, which is about 14.4% lower than that before optimization. The optimized flow characteristic curve still maintains the percentage flow characteristic and meets the requirement of flow capacity K v  ≥ 60 at the maximum opening. The optimization method provides a reference for the structural optimization of the axial flow control valve.

Flow control valves are designed to maintain a constant flow rate regardless of pressure changes. However, standard, two-way design may cause significant energy losses due to the need to maintain high pressure in the supply line. In contrast, the proposed three-way valve allows the required flow rate to be obtained at a supply pressure slightly above the loading pressure. This work included building mathematical and simulation models, conducting numerical simulations in Ansys/Fluent and Matlab/Simulink environments, and verifying the results by initial test bench experiments on a valve prototype. The main contribution provided by the work concerns the proposal of a new valve solution and the estimation of its operational characteristics.

Several studies have utilized commercial Computational Fluid Dynamics (CFD) software to predict and optimize hood performance in reducing odors. In this study, our objective is to simulate the European standard test using CFD software. To achieve this objective, we modeled a full-scale kitchen and hood-mounted Air Flow Control Valve (AFCV) using Ansys Fluent software. We investigated the impact of hood flow rate and AFCV design on capture efficiency and Methyl Ethyl Ketone (MEK) extraction in detail. The analyzes simulate the capture of the heated water vapor and MEK mixture by the AFCV. The analyzes have been validated with experimental results for different flow rate conditions and have been used with confidence to model the MEK diffusion in a realistic kitchen. Thanks to the innovative AFCV created, an 8% improvement has been achieved in capture performance at a flow rate of 100 m'/h. The experiments have been repeated at different flow rates, when evaluated in terms of system pressure required for flow rate and energy consumption, approximately '27% savings were achieved at 400 m\" /h flow. It is great to hear that this study has provided valuable insights for developing high-efficiency ventilation systems (hood) with improved indoor air quality and low energy consumption for central ventilation systems.

Water has the disadvantages of low viscosity, poor lubrication, and easy leakage, which leads to many problems in water hydraulic flow control valves, such as low working pressure and large flow fluctuations. To address these issues, this paper proposes a novel digital flow control valve. The valve uses a linear stepper motor as the driving device. Compared to proportional electromagnets, the thrust and stroke of the linear stepper motor are larger, making the valve more suitable for high-pressure working conditions. Simultaneously, the valve innovatively incorporates a set of pilot valve spool strings at the front end of the pilot valve damping hole. Through controlling the two pilot valves to regulate the pressure difference before and after the damping hole, the flow passing through the pilot valve is maintained stable, thereby making the pressure of the upper chamber of the master valve spool more stable. In comparison to a single pilot valve structure, this design ensures a more stable main valve core position and reduces flow fluctuation. A mathematical and simulation model of the valve has been established, confirming the performance advantages of the new structure. The impact of structural parameters (such as valve core diameter, spring stiffness, and diameter of damping hole) on the stability of flow regulation has been investigated. A genetic algorithm has been employed to optimize the key parameters that influence valve flow stability, resulting in the identification of optimal parameters. The simulation results indicate that the optimized parameters lead to a reduction of approximately 45% in the maximum overshoot oscillation amplitude of the valve flow regulation. A prototype of the new flow control valve was developed, and a test system was established for conducting tests. The test results also confirmed the performance advantages of the valve and the accuracy of the optimal design.

EPANET 2 has been used previously to simulate pressure-deficient operating conditions in water distribution systems by: (a) executing the algorithm repetitively until convergence is achieved; (b) modifying the source code to cater for pressure-dependent outflows; or (c) incorporating artificial elements e.g., reservoirs in the data input file. This paper describes a modelling approach that enables operating conditions with insufficient pressure to be simulated in a single execution of EPANET 2 without modifying the source code. This is achieved by connecting a check valve, a flow control valve and an emitter to the demand nodes. Thus the modelling approach proposed enhances an earlier formulation by obviating the need for an artificial reservoir at the nodes with insufficient pressure. Consequently the connecting pipe for the artificial reservoir (for which additional data must be provided) is not required. Also, we removed a previous limitation in the modelling of pressure-dependent nodal flows to better reflect the performance of the nodes with insufficient flow and pressure. This yields improved estimates of the available nodal flow and is achieved by simulating pressure-deficient nodal flows with emitters. The emitter discharge equation enables the nodal head-flow relationship to be varied to reflect the characteristics of any network. The procedure lends itself to extended period simulation, especially when carried out with the EPANET toolkit. The merits of the methodology are illustrated on several networks from the literature one of which has 2465 pipes. The results suggest the procedure is robust, reliable and fast enough for regular use.