Hydraulic Tube Research Articles

Innovative Coastal Resilience: Design and Application of Hydraulic Geotextile Tubes as Sustainable Breakwater Cores in La Union

The constant assault of waves contributes to the loss of valuable coastal land of La Union, necessitating innovative and sustainable methods to protect the shoreline. In the pursuit of sustainable solutions, innovative technologies such as hydraulic geotextile tubes have emerged as promising contenders for enhancing shoreline protection. This study explores the design and application of hydraulic geotextile tubes as breakwater cores along the La Union shoreline. Due to their permeability and flexibility, hydraulic geotextile tubes offer a viable substitute for conventional breakwater materials. The research aims to provide valuable insights into sustainable coastal management by determining how these tubes can be designed to resist wave forces, ensure stability against hydrodynamic pressures, identify various installation methods, and evaluate their advantages and disadvantages in preventing shoreline erosion and potentially reclaiming sand. The study's findings could inform strategies that balance shoreline protection with environmental preservation. It highlights the interaction between creative engineering solutions and environmental stewardship in addressing evolving coastal challenges.

Flow Patterns of Tetraflouroethane Refrigerant in Different Small Diameter Tubes Used for Vaccine Delivery Boxes

This study aims to determine the flow patterns of tetrafluorethane refrigerant in different small diameter tubes. It attempts to establish a relationship among the temperature, pressure drop, volumetric flow of tetraflouroethane refrigerant in a 900 mm long small diameter tube. Tests are conducted to determine the effect of varying hydraulic tube diameter to the temperature and pressure drop of tetraflouroethane refrigerant in different flow rate. A copper tube with hydraulic diameter of 0.20 mm, 0.25 mm, 0.30 mm, 0.35 mm, 0.40 mm and 0.45 mm were used in this study. For every known hydraulic diameter, there are six (6) test points located in every 150 mm interval. The experimental rig is composed of six (6) pieces of 900 mm long copper tubes for the given hydraulic diameters. Each tube is marked with 150 mm, 300 mm, 450 mm, 600 mm, 750 mm and 900 mm. The markings represent the length of capillary tubes in millimeters where test points are located. A pressure transducer is attached to every test point and is used to measure the pressure drop at every length of the small diameter capillary tube. The result shows that pressure drop increases as the tube hydraulic diameter decreases and attained an evaporator temperature as low as -5 oC. The smaller the diameter of the tube, the more it is effective to give pressure drop for the design of a handy vaccine delivery box refrigeration system.

Modelling the predictive analysis of turbidity removal efficiency in the in-line coagulation and flocculation process

Coagulation and flocculation processes are commonly used in conventional water treatment plants to remove suspended solids from water. However, these methods often suffer from drawbacks such as high chemical consumption, sludge generation, and the need for huge areas, leading to high construction costs. To address these limitations, this study investigated the performance of in-line coagulation and flocculation processes as an alternative to conventional methods. The objectives were to determine the efficiency of in-line coagulation and flocculation, understand the underlying mechanisms, establish optimal operating conditions and design criteria, and to develop theoretical models for predicting turbidity removal efficiency in the in-line coagulation-flocculation process. Experiments were conducted using a continuous setup consisting of a static mixer and a 35-m helically coiled hydraulic tube flocculator.Various operating parameters, including water flow rate (100 – 800 L/hr), initial turbidity (20 – 200 NTU), and coagulant types (aluminum sulfate, poly aluminum chloride, aluminum chlorohydrate, and ferric chloride), were examined. The results demonstrated that aluminum sulfate was the appropriate coagulant for the water characteristics studied, and the in-line coagulation and flocculation processes achieved turbidity removal efficiencies of approximately 91 % under all operating conditions, with a notable 97 % removal efficiency achieved at a liquid flow rate of 600 L/hr, with a Gt value of 21,715 and an overflow rate of 2 m/hr. A prediction model of turbidity removal efficiency was developed, showing good agreement between experimental and predicted removal efficiency model, with an average deviation of about 20 %. This model can aid in determining optimal operating conditions and serve as a hybrid process in future water treatment systems, potentially applicable to other separation processes as well.

Cover Image

The cover image is based on the article Design, optimization, manufacture, and tests of CFRP hydraulic cylinder tube without metal liner: A bionic thorn‐tooth connection by Yao Li et al., https://doi.org/10.1002/pc.28504. image

A robot-assisted tracheal intubation system based on a soft actuator?

Tracheal intubation is the gold standard of airway protection and constitutes a pivotal life-saving technique frequently employed in emergency medical interventions. Hence, in this paper, a system is designed to execute tracheal intubation tasks automatically, offering a safer and more efficient solution, thereby alleviating the burden on physicians. The system comprises a tracheal tube with a bendable front end, a drive system, and a tip endoscope. The soft actuator provides two degrees of freedom for precise orientation. It is fabricated with varying-hardness silicone and reinforced with fibers and spiral steel wire for flexibility and safety. The hydraulic actuation system and tube feeding mechanism enable controlled bending and delivery. Object detection of key anatomical features guides the robotic arm and soft actuator. The control strategy involves visual servo control for coordinated robotic arm and soft actuator movements, ensuring accurate and safe tracheal intubation. The kinematics of the soft actuator were established using a constant curvature model, allowing simulation of its workspace. Through experiments, the actuator is capable of 90° bending as well as 20° deflection on the left and right sides. The maximum insertion force of the tube is 2N. Autonomous tracheal intubation experiments on a training manikin were successful in all 10 trials, with an average insertion time of 45.6s. Experimental validation on the manikin demonstrated that the robot tracheal intubation system based on a soft actuator was able to perform safe, stable, and automated tracheal intubation. In summary, this paper proposed a safe and automated robot-assisted tracheal intubation system based on a soft actuator, showing considerable potential for clinical applications.

Design, optimization, manufacture, and tests of CFRP hydraulic cylinder tube without metal liner: A bionic thorn‐tooth connection

AbstractHydraulic cylinders are widely used in rudder surface control, landing gear retraction of aircraft. The aircraft could benefit a lot on weight reduction, by the application of the carbon fiber reinforced polymer (CFPR) on the hydraulic cylinder. The design, optimization, manufacture of the CFRP hydraulic cylinder tube without metal liner is systematically studied in this article. In terms of structure design, inspired by natural thorn plants, a bionic thorn‐tooth connection structure is designed to connect CFRP and the metal end. Then the theoretical design method of thorn‐tooth is proposed. It also provides a new solution for the generic technology of CFRP‐to‐metal connection. In terms of CFRP parameters design method, an accurate mechanical model of CFRP hydraulic tube is established, the influence law of CFRP parameters on mechanical properties is explored, and the optimization method of CFRP parameters adapted to new characteristics is proposed. In terms of the manufacturing process, the split manufacturing‐combined molding process with high precision and low cost is developed to fit the characteristics of CFRP hydraulic tube without metal liner. The prototype manufactured by the proposed method has a weight reduction ratio of 62.37% while maintaining performances compared to the original metal hydraulic cylinder tube. This research will bring significant performance gains and considerable economic and environmental benefits to aircrafts.Highlights The systematic study of CFRP hydraulic tube without metal liner is presented for weight reduction. The bionic thorn‐tooth connection and its parameter design method are proposed. The CFRP parameters design method of CFRP hydraulic tube is established. A manufacturing process adapted to CFRP hydraulic tube without metal liner is developed.

Optimizing the Probabilistic Neural Network Model with the Improved Manta Ray Foraging Optimization Algorithm to Identify Pressure Fluctuation Signal Features.

To improve the identification accuracy of pressure fluctuation signals in the draft tube of hydraulic turbines, this study proposes an improved manta ray foraging optimization (ITMRFO) algorithm to optimize the identification method of a probabilistic neural network (PNN). Specifically, first, discrete wavelet transform was used to extract features from vibration signals, and then, fuzzy c-means algorithm (FCM) clustering was used to automatically classify the collected information. In order to solve the local optimization problem of the manta ray foraging optimization (MRFO) algorithm, four optimization strategies were proposed. These included optimizing the initial population of the MRFO algorithm based on the elite opposition learning algorithm and using adaptive t distribution to replace its chain factor to optimize individual update strategies and other improvement strategies. The ITMRFO algorithm was compared with three algorithms on 23 test functions to verify its superiority. In order to improve the classification accuracy of the probabilistic neural network (PNN) affected by smoothing factors, an improved manta ray foraging optimization (ITMRFO) algorithm was used to optimize them. An ITMRFO-PNN model was established and compared with the PNN and MRFO-PNN models to evaluate their performance in identifying pressure fluctuation signals in turbine draft tubes. The evaluation indicators include confusion matrix, accuracy, precision, recall rate, F1-score, and accuracy and error rate. The experimental results confirm the correctness and effectiveness of the ITMRFO-PNN model, providing a solid theoretical foundation for identifying pressure fluctuation signals in hydraulic turbine draft tubes.

Sustainable innovation: decentralized hydroelectric power microgeneration in a rural Amazon community

Hydroelectric microgeneration is characterized by low environmental degradation and low production and transmission costs. In this sense, this work investigates the production and storage of electrical energy by gravitational accretion in a rural Amazonian community. Thus, the gutter was used to capture water in a river, directing the flow to a hydraulic ram which pumps the water to a 200-liter reservoir at a height of 3.35 meters. At the bottom of the reservoir was placed a 1/2” register, a hydraulic tube, a flow sensor (Arduino Platform) and a microgenerator (10W). After that, the record was opened for hydroelectric production, and the electrical voltage (Arduino Platform) was monitored by a voltage sensor connected to the poles of the microgenerator. From the results, about the calibration of the sensors, a scale factor was obtained for the voltage and flow sensor equal to 1.27 and 1.458, respectively. With the association of the microgenerators in series, it is possible to produce with 3 microgenerators a voltage of 22 volts at a flow of 2.45 L/min at a height of 3.35 meters. Regarding the adjustment of the system flow model, a speed reduction coefficient of 0.75 was obtained. By storing the energy in a 12 volts battery using 3 microgenerators in series it was possible to charge at a rate of 0.0071 volts per minute. Finally, the prototype has enough voltage to power devices such as batteries, in addition to producing clean, renewable energy from a decentralized source that is commonly wasted.

Soft seal cutting ring system is optimised for thin-walled tubing

Danfoss Power Solutions has developed a soft seal cutting ring system that is optimised for thin-walled tubing. It enables easy, safe and repeatable assembly of hydraulic tubing, providing reliable leak-free operation.

Design, manufacture, and experiments of lightweight CFRP hydraulic cylinder tube without metal liner

AbstractHydraulic cylinders are widely used in aircraft rudder surface control, landing gear retraction, flaps and speed brakes retraction, ground steering driving, and engine thrust reverser control. The huge weight of hydraulic cylinders severely limits the aircraft's potential for increased range, maneuverability, energy efficiency, and carrying capacity. To achieve the maximum weight reduction, the carbon fiber reinforced polymer (CFRP) hydraulic tube without a metal liner is designed in this paper. In response to the lack of a parameter calculation method for CFRP hydraulic tubes, the accurate calculation method is developed through mechanical modeling and analysis of parameter influence law. For the structure design challenges of connection, sealing, and friction of CFRP hydraulic tube without metal liner, we have proposed and verified the wave contour inlaid structure, three leak‐proof solutions of the connection interface, the leak‐proof structure of the wound CFRP body and the seal friction pair. For the difficulties of multi‐material and high‐precision molding, a new process of split manufacturing‐combined molding is developed to achieve high‐precision and low‐cost manufacturing. Finally, the prototype is manufactured and tested by the presented method, and its weight reduction ratio is 56.64% compared with the original metal hydraulic tube. This study has further matured the application of CFRP hydraulic tubes without metal liners and has great lightweight benefits in aircraft.Highlights CFRP hydraulic tube without metal liner is designed to reduce weight. An accurate calculation method of CFRP parameters is developed. Connection structure, leak‐proof structure, and seal friction pair are designed. The high‐precision and low‐cost molding process is innovatively proposed.

Curve Similarity Analysis for Reducing the Temperature Uncertainty of Optical Sensor for Oil-Tank Ground Settlement Monitoring.

A nonuniform temperature field can deteriorate the performance of sensors, especially those working in the field, such as an optical sensor for oil-tank ground settlement (GS) monitoring. In this case, the GS monitoring employs hydraulic-level-based sensors (HLBS), which are uniformly installed along with the oil-tank basement perimeter and are all connected by hydraulic tubes. Then, the cylinder structure of the oil tank itself can create a strong temperature difference between the sensors installed in the sunlit front and those in the shadow. Practically, this sunlight-dependent difference can be over 30 °C, by which the thermal expansion of the measuring liquid inside the connecting hydraulic tubes keeps on driving a movement and, thereby, leads to fluctuations in the final result of the oil-tank GS monitoring system. Now, this system can work well at night when the temperature difference becomes negligible. However, temperature uncertainty is generated in the GS sensors due to the large temperature difference between the sensors in the daytime. In this paper, we measured the temperature where the sensor was located. Then, we compared the results of the GS sensors with their corresponding temperatures and fitted them with two separate curves, respectively. After observing the similarity in the tendency of the two curves, we found that there was a qualitative correlative relationship between the change in temperature and the uncertainty in the sensor results. Then, a curve similarity analysis (CSA) principle based on the minimum mean square error (MMSE) criteria was employed to establish an algorithm, by which the temperature uncertainty in the GS sensors was reduced. A practical test proved that the standard deviation was improved by 73.4% by the algorithm. This work could be an example for reducing the temperature uncertainty from in-field sensors through the CSA method.

Progress of the RADIX (Rapid Access Drilling and Ice eXtraction) fast-access drilling system

Abstract. RADIX (Rapid Access Drilling and Ice eXtraction) is a prospecting drilling system that has been designed, realized and tested on polar ice sheets. The goal of RADIX is to provide rapid, deep access for sampling of ice and downhole physical measurements that inform about ice sheet age and history and the integrity of layering. A 20 mm access hole is drilled with a hydraulic coiled tubing system where the tube consists of a plastic hose. The ice cuttings are flushed to the surface in normal circulation, i.e., between the hose and borehole wall, and can be sampled for analysis. After drilling, a dedicated logger with a 15 mm diameter is deployed into the hole for measuring the geometric orientation of the hole, the temperature profile and the dust content in the surrounding ice (optical dust logger). The equipment has been tested and improved during six field projects in Greenland and Antarctica. It is designed to ultimately drill through a 3000 m ice sheet within roughly 1 week. The greatest depth reached so far was 324 m during the last field project at Little Dome C.

Multi-objective optimization of elliptical tube fin heat exchangers based on neural networks and genetic algorithm

The application of machine learning based on neural networks (NNs) and genetic algorithm (GA) in multi-objective optimization of heat exchangers is studied. Taking the tube fin heat exchanger (TFHE) as the research object, the inlet air velocity and the ellipticity of tubes are taken as the optimization variables. In order to obtain the optimal heat transfer performance and pressure drop performance, Computational Fluid Dynamics (CFD) simulation is carried out for different Reynolds based on the hydraulic diameter numbers (150–750) and tube ellipticity (0.2–1). Then use simulation data to train the Back-Propagation neural networks and establish the prediction model of heat transfer coefficient and pressure drop. The non-dominated multi-objective genetic algorithm with elitist retention strategy (NSGA-II) is used to optimize two prediction results of NNs. Finally, the optimal heat transfer coefficient and pressure drop are given in the form of Pareto front. The optimization results show that when the Reynolds number is 541 and the ellipticity is 0.34, the pressure drop of the TFHE decreases 20%, and the heat transfer coefficient is basically unchanged, whose j/f is 1.28 times as much as that of the original heat exchanger.

Reconstruction of proper numerical inlet boundary conditions for draft tube flow simulations using machine learning

This paper discusses an innovative strategy to determine appropriate mean and fluctuating inlet boundary conditions for the numerical flow simulations of a hydraulic turbine draft tube. Precise and comprehensive measurements at a draft tube inlet are hard to perform and thus rarely available. Moreover, its complex nature and strong sensitivity to imposed inlet boundary conditions render this flow particularly challenging to predict with numerical methods. The innovative strategy uses machine learning to properly reconstruct the incomplete or unknown inlet boundary conditions from available downstream flow information. Reynolds-Averaged Navier Stokes (RANS) and Large-Eddy Simulations (LES) turbulence modeling methods are used to investigate the draft tube and the numerical results are compared to experimental measurements. Reference simulations are first conducted with standard inlet boundary conditions commonly used in previous numerical works. For RANS, the innovative strategy significantly improves the mean velocity profiles and static pressure evolution inside the draft tube. For LES, its use with an artificial upstream extension allows a proper reconstruction of the upstream turbulent field and a more precise and realistic description of the draft tube head losses.

High Flux Isotope Reactor Neutron Spectrum Shape Estimation From Activation Experiment Data

This article provides a comprehensive review of historical irradiation dosimetry available for different locations within the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL). This article includes a summary of the available measured activation target data covering a span of over 15 years and 39 experimental campaigns, including 200 individual sample locations evaluated. Using this broad set of data, we reconstruct historic average neutron spectra shapes for HFIR at various locations, including within the flux trap region, beryllium reflectors, and hydraulic tube (HT) regions, at both the 100- and 85-MW operational power. Our findings indicate that the general axial flux distribution shows a relatively small change in transition from 100- to 85-MW operating power, with differences of −6% to +15% for the thermal energy range and around −16% to +8% for the fast range, indicating a sharper drop-off of the thermal neutron flux away from the axial center. Compared with historical dosimetry estimates of the HFIR flux shape, we generally find a moderately broader axial profile shape for thermal neutrons in the interior target regions for the 100-MW samples evaluated but relatively close agreement for the present 85-MW flux shape for both thermal and fast fluxes.

Perancangan Alat Treker Piston Kaliper Rem Mobil Dengan Sistem Hidrolik

The hydraulic piston tracker is a tool used to press the car's caliper pistons when changing the disc pad. This study aims to design and design a piston caliper treker tool with a maximum strength of 50Kg and to determine the components and dimensions used in this tool. In this study, the main system is hydraulic which converts the pressure to be greater. The pressure produced by this tool is 50Kg or 490.5 N using only the force of the hand of 8.05 N. For the size of this tool it has an overall length of 27 cm, a retaining width of 11.5 cm, a lever length of 20 cm and a hydraulic tube diameter. 3 cm. main material for hydraulic cylinder chrome steel s30c 48 (Kg/mm2), low carbon steel plate (ST42) 36 (Kg/mm2), bolts, handles and levers Low carbon steel (ST42) 36 (Kg/mm2).Key words : Tool, Treker, design, hydraulic

Cold-rolled Ti-Al-V-Zr-Fe titanium alloy tubing with outstanding tensile properties

Increasing the operating pressure of the hydraulic lines is one of the directions to improve the comprehensive performance of the hydraulic system of an aircraft. However, the existing Ti-3Al-2.5V (limited strengths) and Ti-6Al-4V (poor cold formability) alloy tubing are not applicable to the hydraulic lines with an operating pressure over 28 MPa. In this work, a new type of Ti-Al-V-Zr-Fe titanium alloys were developed and the thin-walled seamless tubing was fabricated by cold rolling. After being annealed at 550 °C, Ti-4Al-2V-1.2Zr-0.3Fe (σb=1029 MPa, δ = 19%) and Ti-4.5Al-3V-1.5Zr-0.45Fe (σb=1102 MPa, δ = 18%) alloy tubing have outstanding room temperature tensile properties mainly due to dislocation strengthening. In addition, the strong radial textures in Ti-Al-V-Zr-Fe titanium alloy tubing, which increase the average Schmid factors under axial tensile loads, play a vital role in the strengthening contributions from dislocations and in the plastic deformation mechanisms. This work is of theoretical importance and practical value for developing aerospace hydraulic tubing with an excellent combination of mechanical properties.

Locomotion via Active Suction in a Sea Star-Inspired Soft Robot

Some marine animals, such as sea stars, have developed versatile adhesive appendages that can be used for a variety of behaviors including sticking to surfaces, manipulating objects, and locomoting. These appendages couple reversible adhesion capabilities with muscular structures that can do work on the world while still being soft enough to conform to various surfaces and to squeeze through tight spaces. We took inspiration from the hydraulic tube feet of sea star to create modules consisting of soft active suction discs and soft pneumatic linear actuators. Tube feet convert fluid motion into linear actuation using soft tubes that are constrained radially. In this work, we study the tradeoff between the stiffness of such radial constraints, and the ability of the linear actuators to apply axial forces. The adhesive force of the suction disc is dependent on both the pressure differential between the suction cavity and the environment and the deformation within the body of the disc while it is being loaded. We show that the tube foot modules are capable of creating locomotion over flat surfaces, up small steps, and in a confined space due to the redundancy caused by an array of actuators. We also show that active suction not only enables the use of softer tube foot actuators, but that sensing this active suction line provides feedback to increase the efficiency of locomotion over obstacles.

Flow and heat transfer characteristics of coal-based rocket kerosene in mini-tube with ultra-high parameters

Coal-based rocket kerosene as a new aerospace fuel and active regenerative cooling technology coolant, in order to make it widely used in engineering, the flow and heat transfer experiments were carried out for the first time under the actual working parameters of the rocket engine. The effects of heat flux (2–33.8 MW·m−2), mass flow rate (8000–48,000 kg·m−2·s−1), and inlet temperature (323–473 K) were investigated. The results indicated that as the heat flux increases, the total pressure drop and friction factor first decreased and then increased. With Reynolds numbers 3.1 × 104 and 7.6 × 104 as the boundary, the flow was in the hydraulic smooth tube region, transition region and turbulence rough tube region respectively. Increasing the inlet temperature can inhibit the heat transfer deterioration caused by the entrance effect. Higher heat flux can be maintained by increasing flow rate. When the wall temperature just exceeded the pseudo-critical temperature, the rate at which the heat transfer coefficient increased with the increase of heat flux became higher. Considering the influence of various parameters to modify classic correlation, and using the probability density function to modify the thermophysical properties of coal-based rocket kerosene, a new Nusselt number correlation was proposed.

수로식 마이크로 수력설비 구축에 대한 고찰

As the importance of de-carbonization increases, interest in the development of clean energy is gradually expanding. New and renewable energy is the basis of clean energy. Among renewable energies, the oldest, well-established energy conversion technology, and the highest efficiency is hydroelectric energy. Hydropower is classified into large hydropower, medium hydropower, small hydropower, micro hydropower, and pico hydraulic power according to the power generation output. In the case of Korea, the target of output that can still be developed is micro-scale hydropower. In particular, there are many places in the small rivers and mountainous areas where the water of the rivers flowing through the road can be used. In such a place, it is possible to construct a run of river type power generation facility. In order to expand the supply of micro hydroelectric power generation, there are various considerations during construction. Intake weir and a water tank are required to secure a certain amount of water, a hydraulic tube is required to convert this into potential energy, and water turbine is required to convert potential energy into kinetic energy. In order to convert mechanical energy due to aberration into electrical energy, a generator is required. In this paper, we introduce a method for reducing construction cost and convenient maintenance without changing the flow of water through the change of the waterway type compared to the existing run of river type hydroelectric power generation.