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Microfluidics offer microenvironments for reagent delivery, handling, mixing, reaction, and detection, but often demand the affiliated equipment for liquid control for these functions. As a helpful tool, the capillary pressure control valve (CPCV) has become popular to avoid using affiliated equipment. Liquid can be handled in a controlled manner by using the bubble pressure effects. In this paper, we analyze and categorize the CPCVs via three determining parameters: surface tension, contact angle, and microchannel shape. Finally, a few application scenarios and impacts of CPCV are listed, which includes how CPVC simplify automation of microfluidic networks, work with other driving modes; make extensive use of microfluidics by open channel, and sampling and delivery with controlled manners. The authors hope this review will help the development and use of the CPCV in microfluidic fields in both research and industry.

The article identifies some of the forces acting on hydraulic valves used in the civil and military vehicles. Particular attention was paid to the single-stage electrically controlled “on/off” hydraulic directional control valve. Special attention was focused on vibrations of hydraulic directional valve four ways, three positions (4/3) controlled by typical solenoids. Military vehicles can be a source of vibrations in low and high range of frequency. The spectrum of vibrations frequency is wide in this case. The value of the natural frequency of vibrations of the hydraulic directional control valve spool, whose body was affected by mechanical vibrations, was estimated. The paper shows that the natural vibrations of the directional control valve spool can coincide with the frequency of external vibrations acting on the valve from the ground. The mathematical description takes into account that when the spool is overdriven, the oscillating movement of the directional control valve spool is described by a model that takes into account the nonlinearity resulting from the fact that the spool is in the extreme position—it is a poor nonlinear mechanical system. The results of theoretical considerations were confronted with the results of experimental research. In addition, the presented modified model was used to assess the impact of the capacitance change on the value of the amplitude of pressure pulsations caused by the vibrations of the directional control valve spool.

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.

The passive suspension seats have been widely used in off-road vehicles, but the drivers still suffer from the greater vibration and shock transmitted from the rough road, adversely affecting the drivers’ health and vehicle handling safety. Although active suspension seats have been researched and developed in engineering and academia for more than 30 years, they have rarely been applied in the industry due to the complex electrical structures and high costs. In this paper, a novel valve damping control system (VDCS) used in the off-road vehicle seat suspension is proposed and studied, which is a mechanical semi-active damping control system without ECUs and sensors. Firstly, the structures and working principles of VDCS are described in detail. Then, the dynamics model of the seat suspension system with VDCS is established, and simulation and experimental research are performed to evaluate its shock and vibration isolation performance. The results show that a seat suspension with VDCS is much better for isolating vibrations and shocks than one with a traditional manual adjustment damper in the whole workspace.

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.

Cage-type control valves are widely used in process industries, but cavitation can occur when the valves are used in extreme high-pressure drop and large volume flow rate conditions. In this study, the cage-type control valve with improved valve cages is introduced, and its flow and cavitation characteristics are compared with other cage-type control valves with no dead zones in the regulation process. Two cage numbers and four valve cage structures are studied. Numerical simulations are conducted, and their accuracy is validated using experimental results. Results show that cage-type control valves with valve cage 1 have the maximum flow coefficient and cavitation intensity under the same cage number. Cage-type control valves with valve cage 2 have the minimum flow coefficient but medium cavitation intensity. While cage-type control valves with improved valve cages have a medium flow coefficient but minimum cavitation intensity, and water vapor volume can be reduced by 2-8 times compared with cage-type control valves with the valve cage 2. Furthermore, for cage-type control valves with improved valve cages, the cavitation intensity, and flow coefficient decrease as the cage number and groove height increase.

Aiming at the most important control link of electric regulating valve in automatic distribution control system of natural gas station, this paper proposed to use single neuron adaptive Proportional-Integral-Derivative (SNA-PID) algorithm to make up for the problems of the traditional Proportional-Integral-Derivative (PID) algorithm, such as the difficulty of parameter setting and the inability to adapt to system interference. In order to compare the performance of the algorithm, the transfer function between the valve opening of the electric regulating valve on the branch of the gas transmission system of a natural gas station was taken as an example to simulate various practical application scenarios, and the control performance of the two algorithms was studied in detail. Finally, the practical engineering application and the performance verification of the algorithm were carried out in a natural gas distribution station in Jiangxi Province. The results showed that, compared with the PID algorithm, the SNA-PID algorithm can automatically adjust its own algorithm parameters, greatly reduce the number of valve operations during the adjustment process, and control the valve opening more smoothly, adjust the branch pressure more quickly and effectively, and also has a strong anti-interference ability. Therefore, SNA-PID algorithm is more suitable for the automatic distribution control system of natural gas station than the PID algorithm.

The solenoid valve for traction control valve (TCV) responsible for the automatic vehicle hold (AVH) function of electric vehicles require a continuous supply of power to the magnetic coil in order to operate. When power is continuously supplied, heat is generated because of the resistance of the magnetic coil, which leads to deterioration of the periphery of the solenoid valve and deteriorates durability. To prevent this, when power is applied to the solenoid valve for TCV for more than a certain period of time, the power supply is automatically turned off and the AVH function is controlled to be performed by the electronic parking brake (EPB). In this study, we designed, manufactured, and verified the permanent magnet solenoid valve of TCV for AVH that can minimize unnecessary power consumption of electric vehicle batteries. For the design of the permanent magnet solenoid valve, the location, polarity direction and specifications of the permanent magnet within the solenoid valve were studied through finite element analysis. In order to check whether the braking function by the permanent magnet is maintained even when the current is cut off at AVH’s TCV solenoid valve, electronic control unit (ECU) and electronic stability control (ESC) were manufactured and evaluated for actual vehicle testing. Therefore, it was possible to manufacture a permanent magnet solenoid valve that minimizes unnecessary power consumption of the battery because it does not require power supply even when the car is stopped for a long time in the AVH function of the electric vehicle.

ACURATE neo2 is an open-cell, supra-annular, self-expanding transcatheter heart valve that is commercially available in over 50 countries but has not previously been evaluated in a randomised trial. ACURATE-IDE aimed to prospectively evaluate the safety and efficacy of transcatheter aortic valve replacement (TAVR) with the ACURATE neo2 valve compared with commercially available valves for the treatment of severe symptomatic aortic stenosis. In this multicentre, randomised, controlled, non-inferiority trial, patients with symptomatic severe aortic stenosis and any level of surgical risk were recruited from 71 medical centres in the USA and Canada. Eligible patients were randomly assigned (1:1) to TAVR with ACURATE neo2 or one of the control valves, SAPIEN 3 (SAPIEN 3 or SAPIEN 3 Ultra) or Evolut, using permuted block randomisation with a pseudo-random number generator, and stratified by the clinical investigation site and type of control valve. All devices were implanted according to the manufacturer's instructions. The primary endpoint was a composite of all-cause mortality, all stroke, and rehospitalisation at 1 year, tested for non-inferiority using a Bayesian approach. The primary analysis was performed in the intention-to-treat population and sensitivity analyses were done in the implanted population. The non-inferiority margin was 8·0%. This study is registered with ClinicalTrials.gov, NCT03735667, and is ongoing. Between June 10, 2019, and April 19, 2023, 1500 patients were recruited, of whom 752 were randomly assigned to the ACURATE neo2 group and 748 to the control group. The median age of participants was 79 years (IQR 74–83). 778 (51·9%) of 1500 patients were female and 721 (48·1%) were male. At 1 year, the posterior median probability of the primary composite endpoint was higher in the ACURATE neo2 group (16·2% [95% Bayesian credible interval 13·4–19·1) than in the control group (9·5% [7·5–11·9]; between-group difference 6·6% [3·0–10·2]). The upper bound of treatment difference exceeded the prespecified non-inferiority margin of 8%, with a posterior probability of treatment difference of >0·999. At 1 year, the ACURATE neo2 group, had significantly higher Kaplan–Meier rates of the composite endpoint of all-cause mortality, all stroke, and rehospitalisation (14·8% [95% CI 12·5–17·6] vs 9·1% [7·2–11·4]; hazard ratio [HR] 1·71 [95% CI 1·26–2·33]; p=0·0005). At 1 year, all-cause mortality occurred in 36 of 752 patients in the ACURATE neo2 group versus 28 of 748 patients in the control group (HR 1·30 [95% CI 0·80–2·14]), stroke in 41 patients versus 25 patients (1·68 [1·02–2·75]), and rehospitalisation in 38 patients versus 25 patients (1·57 [0·95–2·61]). Cardiovascular mortality (3·7% vs 1·8%, p=0·024) and spontaneous myocardial infarction at 1 year (2·4% vs 0·7%, p=0·0092) were more frequent in the ACURATE neo2 group than in the control group. Prosthetic valve aortic regurgitation (central plus paravalvular) at 1 year was significantly more frequent in the ACURATE neo2 group than in the control group (mild aortic regurgitation 42·5% vs 24·8%, p<0·0001; moderate 4·4% vs 1·8%, p=0·0070; severe 0·5% vs 0%; p=0·12). In patients with symptomatic severe aortic stenosis, TAVR with ACURATE neo2 did not meet non-inferiority and resulted in significantly worse outcomes with respect to the primary endpoint of composite of all-cause mortality, all stroke, and rehospitalisation at 1 year when compared with commercial valves. Boston Scientific.

In order to maintain the performance of a fuel cell vehicle, it is essential to maintain a constant temperature of the stack. Therefore, it is very important to distribute the optimal coolant flow rate to each major component under very diverse and rapidly changing dynamic operating conditions. The part responsible for this is a five-way electric coolant valve. Therefore, this study aims to investigate transient dynamic flow characteristics of the fluid flow through a five-way electric coolant valve (PCCV: Penta-Control Coolant Valve). To achieve this goal, this paper attempts a three-dimensional dynamic simulation of the fluid flow through the valve using a commercial CFD solver with moving mesh technique to consider flow inertia and dynamic flow in the opening and closing stages of the ball valve rotating motion. The dynamic flow characteristics and the thermal mixing inside the PCCV ball valve during the opening and closing stages are analyzed. It was found that the discrepancies between dynamic and steady-state simulations are remarkable when fluxes with different levels of enthalpy and momentum flow into the PCCV, leading to strong flow interference and flow inertia, while the discrepancies are relatively small at low rotation speed and weak flow interference. Subsequently, the effect of the dynamic flow characteristics of the valve on the dynamic thermal mixing characteristics at two different ball valve rotation speeds and rotation directions are investigated. It was found that the dynamic flow and thermal mixing characteristics inside the PCCV are greatly affected by the rotation speed, rotation direction, and degree of flow interference between fluxes. It also helps design better coolant control strategies and improves the FCEV thermal management system.