Suspension Movement Research Articles

Analysis of nano-encapsulated phase change material confined in a double lid-driven hexagonal porous chamber with an obstacle under magnetic field

The magnetohydrodynamics (MHD) mixed convection of nano-encapsulated phase change material (NEPCM) contained within a double lid-driven hexagonal porous chamber contacting a square-shaped obstacle is numerically examined in this study. The enclosure's upper and lower walls are moving at the same speed; while the square-shaped obstacle is hot, the side walls are stationary and cold. The Galerkin Finite Elements method (GFEM) was applied to deal with the governing equations and their boundary conditions. The flow and thermal fields are presented and discussed in relation to the effects of the moving wall direction, moving wall velocity, magnetic field strength, and chamber permeability. These studied factors are examined in these ranges: Ha = 0 to 100, Da = 10–5 to 10–2, ø = 0 % to 5 % and Re = 1 to 500. The results showed that the heated body is surrounded by a circular flow when the two walls move in opposite directions. However, thermal activity is enhanced and strengthened when the upper and lower walls move in the same direction. According to the findings, the concentration of NEPCM particles has little effect on the quality of the thermal transfer and decreasing the space's permeability makes it more difficult for the suspension to move and reduces the amount of thermal energy transferred between the cold and hot surfaces. Additionally, a decrease in thermal transfer occurs when the intensity of the magnetic field is increased, which has a negative impact on the suspension's movement.

Adaptive Control of Two-Pendulum Suspension of Overhead Crane

When constructing the bridge crane control law, a two-pendulum model with a hook suspension, on which the transported load is suspended, and a load suspension is considered. This model more accurately describes the dynamics of cargo movement, which is especially critical in a number of crane operating modes, including cases when the mass-inertial parameters of the cargo are close to the hook. A mathematical model of the two-pendulum mechanical system of the crane suspension along one axis of its movement is described, taking into account the effect of friction forces when moving the crane trolley and wind disturbance acting on the transported cargo. Also, there is presented linearized model of hook movement with control action in the form of preset speed of crane trolley movement. The latter corresponds to the use of a servo motor or stepper motor to control the trolley. On the basis of the obtained linearized model, an adaptive control law is constructed using a scheme including an algorithm for current parametric identification, an implicit reference model, "simplified" adaptability conditions with direct tracking of hook movement (through it — cargo movement) by the properties of the assigned reference model. This control law allows you to build crane control under the current parametric uncertainty of the properties of the crane, the transported cargo and external disturbances (only approximate information about some parameters is assumed). It is shown that in the case when the natural frequency of the assigned reference model is less than that for the hook suspension, the proposed control law generates asymptotic movement of the hook (load) to the assigned point and damping of angular oscillations of the hook suspension and load suspension. For more efficient damping of angular oscillations in case of large values of load moment of inertia, it is proposed to supplement preset value of hook movement with damping movements based on angular movement of load suspension. Model examples supporting theoretical conclusions are given. It is shown that the proposed solution makes it possible to build a bridge crane control under the action of measurement noise and control signal delays.

Modelling and Analysis of Power-Regenerating Potential for High-Speed Train Suspensions

Sustainable technologies in transport systems have attracted significant research efforts over the last two decades. One area of interest is self-powered devices, which reduce system integration complexity and cost with an undoubtedly great potential for improving adaptability and developing sustainability in railway transport systems. One potential solution is a regenerative suspension system, which enables the suspension movements and dissipated energy to be converted into useful electricity. This paper explores the application of hydraulic–electromagnetic regenerative dampers (HERDs) under realistic railway operating conditions for a high-speed train (HST). A vehicle-track-coupled dynamics model is employed to evaluate the regenerative power potential of an HST suspension over a range of operating conditions. The work considers typical route curvature and track irregularity of a high-speed line and speed profile. It was found that power could be regenerated at a level of up to 5–30 W and 5–45 W per generation unit when fitted to the primary and secondary dampers, respectively. Such power-regeneration levels were adequate to supply a variety of low-power-consumption onboard components such as warning lights and wireless sensors. Further analysis of the carbody loading level also was carried out. The analysis revealed that, in the case of a high-speed journey, poor track geometry, low curvature, and reduced carbody weight increased the quantity of regenerative energy harvested by the HERDs. It was concluded that a suitable HERD design could be achieved that could facilitate the development of a smart railway damper that includes both self-sensing and power-generation functions.

Practical aspects in modeling the air conveying modes of small–piece food products

A mathematical and physical model of the critical pneumatic conveying modes has been developed to ensure the calculation and construction of pneumatic product pipelines of continuous operation. The model takes into consideration the technological conditions of gas suspension movement; the laws of movement of individual fine particles, accounting for their impact interaction and decompression, as well as the actual boundary conditions for a food product movement. The parameters of the zone of dynamic destruction of the layer of a small-piece food product by impact airwave were experimentally studied; the results of the calculation have been compared with the experimental data. The process of managing critical pneumatic conveying modes has been theoretically described, based on the proportional elements and feedback (a current loop of 4‒20 mA); the process of destruction of the cluster of products by airwave and controlled decompression has been studied. The process of pneumatic conveying of a small-piece product at the experimental bench system has been examined. As well as the process of moving the material in the product pipeline, which is controlled by compressed air pulses, to maintain the modes of operation. The following has been established: pressure losses caused by the movement of clean air; additional pressure losses resulting from the movement of the material; the loss of pressure required for transporting in a suspended state on a vertical stretch. A model has been developed to calculate the coordinates of a product particle when it collides with the inner surface of the product pipeline, as well as a change in its kinematic characteristics. The developed model makes it possible to determine the rational modes of pneumatic conveying and possible energy costs in the processing of various small-piece materials. The rational pneumatic conveying regimes have been determined, as well as possible energy costs in the processing of small-piece materials. As the time of supplying compressed air in the product pipeline increases, the number of product particles reaches a maximum in the range of 0.1...0.2 s. The compressed air flow rate, depending on the value of inlet mainline pressure P (0.1…0.3 MPa), is 80…160 (Nl/min). A general approach to the modeling of pneumatic conveying systems has been proposed

Feasibility of a kneeling train to improve platform–train interface for passenger boarding and alighting

Railway operators and infrastructure companies strive to optimise the flow of passengers on and off vehicles whilst aiming to minimise accidents at the Platform-Train Interface (PTI). An ideal solution (already available in some situations) would be a step-free access to aid efficient boarding for everyday passengers and those with additional needs or reduced mobility. Out of many solutions existing today, a ‘kneeling vehicle’ seems a possible solution due to the opportunity to minimise the step and gap distances. In this paper, the viability of an assumed kneeling mechanism retro-fitted to a contemporary suspension architecture is assessed by evaluating the possible improvement in the step/gap distances based on a detailed model of suspension movement. It is shown that for many different infrastructure scenarios that significant improvements in the PTI are shown for a modest and achievable kneeling action. This paper also address fundamental operational concerns of a kneeling vehicle by assessing gauging (with respect to infrastructure and adjacent vehicles) and pantograph interaction.

Fatigue behavior for design optimization of parking brake bracket connections

The creation and implementation of brackets have become highly significant in the quality and safety of manufacturing parking brake cables. Moreover, the ability to establish fatigue loads and their effects on the brackets in the vehicle route is now highly important in the design and development process. It is thus crucial to develop an accurate numerical model using computer aided engineering to establish patterns of fatigue during bracket manufacturing. The purpose of this research is to identify the importance of computer aided engineering in bracket optimization, for example in parking brake cables. The key objective of the research is to establish the level of strain exerted on a bracket during oscillation (fatigue) resulting from suspension movement of vehicles. Furthermore, it intends to lower the vehicle's weight and cost by replacing metal brackets with plastic ones.

Random forest, support vector machine, and neural networks to modelling suspended sediment in Tigris River-Baghdad.

Suspended sediment is one of the most influential parameters on the water bodies' pollution. It can carry different pollutants with different concentration through the suspension movement in the flow. Therefore, it is of utmost importance to monitoring or modelling these loads so that an accurate sediment reduction strategy can be adopted. However, the monitoring process is laborious and time-consuming task. Thus, modelling is suggested as an alternative method. In this study, three different methods of artificial intelligence (i.e., random forest, support vector machine (Radial Basis Function), and artificial neural network) were employed to model and predict the suspended load at Sarai Station in Baghdad. To this end, observed flow rate (m3/s) and the corresponding suspended sediment concentration (mg/l) measured over the periods 1962-1981 and 2000-2010 were collected. Auto and partial correlation was used to identify the best combinations of input model data. The data was randomly partitioned into 75% for training and 25% for validation. The confidence interval was hypothesized to assess the uncertainty in the observed and predicted data. Whereas, the k-fold cross validation was used to quantify the uncertainty in the modelling results. The predictive modelling results for the three evaluated methods were assessed based on R2, RMSE, and NSE coefficient. Results show that random forest has the superior performance among the others. The total suspended sediment transported was estimated to be 72,734,852 ton during the period 2000-2010.

Investigation of the influence of the length of the rope suspension of the bridge crane and the length of displacement of the cargo in the controlled sway mode on the time of displacement

The formulas for a complete analytical solution of the problem of moving cargo on a pendulum suspension of constant length along a given trajectory in a plane setting are presented. To set the desired trajectory as a time dependence of the linear horizontal coordinate of the cargo in a limited time interval, two-point Hermite polynomials are used. The field of application of the method is the automatic control of the movement of bridge and gantry cranes, as well as modeling of crane working processes. The application is limited to small angles of deviation of the cargo rope of the bridge crane from the gravitational vertical. The method makes it possible to quickly synthesize the optimal trajectory of the point of cargo suspension movement, which accurately provides the required trajectory of cargo movement. For a series of constant values of the maximum acceleration developed by the point of suspension of the cargo during a single transient process, graphs of the moving time dependences from moving length and cargo rope length are revealed. The functions obtained are not smooth and have a fracture. This makes it impractical to approximate them using the regression equation, due to the high error of the latter. The resulting graphs can be used to determine the time of movement of the cargo depending on the specified length of moving, the length of the cargo rope and the maximum acceleration developed by the drive of the cargo suspension.

Dynamic target template matching for railway catenary suspension motion detection in wind area

A dynamic target template matching method was proposed to identify railway catenary suspension movements of wind-induced vibration in wind area. Catenary positioning point was taken as the target template, which was compared with equal-sized image sequentially using the proposed matching difference. And, three-dimensional contour map of matching difference value at each sub-area was obtained, where the target pixel coordinates were determined by the minimum matching difference value. Considering the complex imaging condition, the target template was updated by the detected target image to sense the gradual change of illumination conditions like brightness and contrast. Furthermore, to eliminate detecting errors due to wind-induced camera vibration, both static and moving target templates were identified for acquiring the absolute motion of the moving target. Finally, validation test was performed with animation in PowerPoint. The calculated target displacement agrees well with theoretical motion with maximum relative error of 1.8%. And experiment application was conducted at site by analyzing the relationship between detecting displacement and wind speed. Results indicate that the proposed dynamic target template matching method can meet required engineering precision and provide an effective way for wind-vibration safety research of railway catenary system in wind area.

Analysis of the rotational capability of the utilization of range of a spherical joint used in a passenger automobile McPherson suspension

In this paper a method is presented how to determine the utilization of range of rotational ability of a ball joint used in a passenger automobile McPherson suspension. A portable measurement arm was used to measure some vehicle’s suspension geometry points as well as the geometry of suspension components. Based on the initial measured data a simulation model was used to estimate the real geometric parameters of the suspension and of the attachment points at the chassis. The damper module’s top mount movement as well as the stiffness characteristics of the control arm bushing allow to simulate the utilization of range of motion capability of the spherical joint as result of the suspension movement under external loads. These loads can result from pass over a bump or cornering movements. The rotational ability of the ball joint and its applied loads can be input for further stiffness analyses by making use of FEM software.

Vibration control of an energy regenerative seat suspension with variable external resistance

Abstract In this paper, an energy regenerative seat suspension with a variable external resistance is proposed and built, and a semi-active controller for its vibration control is also designed and validated. The energy regenerative seat suspension is built with a three-phase generator and a gear reducer, which are installed in the scissors structure centre of the seat suspension, and the vibration energy is directly harvested from the rotary movement of suspension’s scissors structure. The electromagnetic torque of the semi-active seat suspension actuator is controlled by an external variable resistor. An integrated model including the seat suspension’s kinematics and the generator is built and proven to match the test result very well. A simplified experimental phenomenon model is also built based on the test results for the controller design. A state feedback H ∞ controller is proposed for the regenerative seat suspension’s semi-active vibration control. The proposed regenerative seat suspension and its controller are validated with both simulations and experiments. A well-tuned passive seat suspension is applied to evaluate the regenerative seat’s performance. Based on ISO 2631-1, the frequency-weighted root mean square (FW-RMS) acceleration of the proposed seat suspension has a 22.84% reduction when compared with the passive one, which indicates the improvement of ride comfort. At the same time, the generated RMS power is 1.21 W. The proposed regenerative seat suspension can greatly improve the driver’s ride comfort and has the potential to be developed to a self-powered semi-active system.

Adaptive Event-Triggered Control for Vehicle Active Suspension Systems With State Constraints

To reduce the communication burden between the controller and the actuator, this paper proposes an adaptive event-triggered control method for nonlinear vehicle active suspension systems with state constraints. Without determining a priori knowledge of the control direction, the presented approach can be implemented based on the constrained adaptive technique for simultaneously addressing the physical state limitations in the presence of parametric uncertainties and compensating the measurement error caused by the event-triggering mechanism. A Lyapunov stability proof guarantees that the closed-loop suspension system is stable, and the suspension movement limitation is not violated. A designed example is given to illustrate the effectiveness of the presented controller for improving the vehicle ride performance.

Method for the measurement of the stratification of concentrated suspensions

A simple, fast and precise method for evaluation of precipitate formation kinetics and its amount in concentrated suspensions that are stored in closed containers after production has been developed. The method is based on the measurement of the mechanical pendulum period change over time. The principles of the development of this method are presented: theoretical fundamentals of measurement using this method have been analyzed; it was proved that the swing period and amplitude change rate are informative pendulum parameters; a pendulum variant was determined experimentally that allows to avoid the error introduced by the movement of suspension inside the container and reduces the requirements for the container mass uniformity; it was determined that in order to reduce the error it is appropriate to start the period duration measurement from the 5 period from the beginning of the swing; the dependence of the swing period on the mass of the precipitate was evaluated experimentally.

Modeling and Process Features of Plug Flow Reactor with Internal Recirculation for Biomass Pyrolysis

A new fluidized bed design is considered for the pyrolysis of biomass, in a plug-flow with internal-recirculation (PFIR) arrangement, where the movement of solids from feed zone to product zone and the circulation within a closed loop are achieved, by the use of directional high-speed tuyeres that induce both the suspension and horizontal movement of the charge. Separation between feed and product zones is provided through one or more underflow weirs. Wet and hard-to-fluidize biomass is targeted, where fluidization and pyrolysis of the feed is achieved by the internal hot sand recirculation. Plug flow can allow for both stages (pyrolysis and heating) to occur inside a single vessel, but at separate zones. Computer simulation of the PFIR reactor is demonstrated to verify that plug-flow with internal- recirculation can be achieved under reasonable operating conditions. A commercial software (CPFD-Barracuda) is used, which shows promising results, including: solids circulation due to directional tuyeres; large solids mass transport rates relative to reactor size; and controllability of the circulation rate via tuyere velocity. It is shown that the underflow weir(s) offer little resistance compared to the frictional losses and, therefore, multiple zones within a single reactor can be achieved with little impact on the solids recirculation rate. The horizontal mass flux is shown to occur predominantly near the bottom Tuyeres (inclined jet zone), hence enabling the underflow weir to effectively separate the feed and product zones, with a small bottom passage for the solids.

Research on Submarine Straight-Line Track Control Underwater Based on Nonlinear Proportion Differential

With the development of deep submergence technology, submarine is widely used in many aspects as marine analysis and detection of marine resources. For the reason of strong nonlinearity and coupling in submarine exercise, it is difficult to get satisfactory control effect by conventional control method. In order to control objective of stable straight-line suspension underwater, how to control the change of rudder angle to stabilize attitude and improve the control performance is researched from feature analysis to submarine. Aiming at improving the global stability, kinetic character of straight-line suspension movement underwater is analyzed and modeled firstly, and model of nonlinear relationship about change of rudder angle and attitude is built then. Based on the conditions of global stability asymptotically of submarine tracking control underwater and the physical significance of tracking control by nonlinear proportion differential, a controller is designed for controlling horizontal rudder angle and vertical rudder angle by dynamic feedback, which achieve the balance of tracking controlling both in local and global and guarantee global stable convergence asymptotically. At last, the stability, effectiveness, and global convergence of controller are proved by the simulation experiment.

Design and fabrication of magnetic shock absorber

In a vehicle, shock absorber reduces the effect of travelling over rough ground, without shock absorber the vehicle would have a bouncing ride, as an energy is stored in the spring and then released to the vehicle, possibly exceeding the allow range of suspension movement [1]. Control of excessive suspension movement without shock absorption requires stiffer springs, which would intern gives a harsh ride. Shock absorber allows the use of soft springs while controlling the rate of suspension movement in response to bumps [2]. In this project a new suspension system based on magnetic power which can be used in automobile in future. The suspension system consists of magnets freely moving inside the cylinder with their same poles facing each other. Since the magnetic poles repel each other while moving closer, the up and down spring action is obtained. Keywords: Suspension System, Magnetic Power, Magnetic Poles.

Distributional characteristics of grain sizes of surface sediments in the Zhujiang River Estuary

Distributions of the parameters of sedimentary grain sizes and their correlations were studied to trace the sources of silts and their movement trends in the Zhujiang River Estuary based on the analyses of grain sizes from more than 1 080 sedimentary samples. The distributions of the median diameter, public value, quartile deviation, and skewness of sediments were complex in the Zhujiang River Estuary mainly because of the impact of the matter source regions, distances from the source regions, and hydrodynamic conditions, such as waves, tidal currents, and coastal currents. Analyses of the parameters of the grain sizes for the various types of sediments showed that the distributions of the surface sediments in the Zhujiang River Estuary were controlled by many factors. Their matter sources were mainly the sediments discharged from the runoffs and ebb tidal currents, and from the open sea. The sediments mainly moved by suspension movement. The silts formed a large area of sediments with suspended fine silts in the Zhujiang River Estuary by internal adjustment transportation in the area, and moved toward the western coast of the Zhujiang River Estuary under the effect of Coriolis forces and coastal currents.

Redesign of Drive Shaft`s tripod Assembly, to improve the performance & reduce failure

The aim of the project is to enhance the performance of the drive shafts tripod assembly to reduce failure and to increase the performance of the product. Drive shaft transfer the engine power to the wheels and it allows for steering and suspension movement and reduce vibration for the driver. Loss of drive in the vehicle due to inboard / Tripod assembly damage (Drive shaft inboard joint failure). Reducing the Failure of drive shaft improves performance and warranty life for both existing product and new product. Even though the interconnecting shaft was intentionally made for fail during excessive loading, unfortunately the inboard joint fractures during static testing and on field. The failure due to the inboard joint (Tripod assembly roller damage) is high. Objective is to find the Root cause for tripod assembly Failure, by the Adams simulation case study, It has been observed bottom needle only getting loaded with the maximum load of 27KN and to improve the static load test load has to be uniformly distributed or roller and Needle geometry has to be improved to withstand the load. The aim of the project is to design and develop a tripod assembly withstand Minimum 1600 Nm. design.

Vehicle Dynamics Conversion into Power (Dynapower)

This paper aims to develop a new system that converts vehicle motion into electrical energy. It exploits aerodynamics and ground-wheel dynamics to generate power. When the vehicle moves, an aerodynamic phenomenon is created on surfaces and the suspensions vibrate. The main objective consists on the exploitation of these dynamics to produce power and charge the batteries. A vehicle equipped with anemometer and sensors is used in order to invent a new device.First, we present a wind turbine design and use cases. Then, we develop a new system which can convert suspension movement into power. The whole system is called “DynaPower”.

Low-voltage electrophoretic deposition of polyetherimide through quarternization and re-imidization reactions

The electrophoretic deposition (EPD) process successfully applied for the deposition of quarternized polyetherimide (q-PEI) emulsion on the Cu surface in the relatively low voltage range of 2∼7 V. Allowing the rheological movement of q-PEI suspension drops to move to the cathode, this voltage level allowed q-PEI (or PEI) coating to be in the thickness range in a few micrometers within 300 sec. The coating thickness increased with the applied voltages and seemed to reach a plateau with time seemingly allowing a stable control of EPD operating conditions. The low-voltage in EPD minimized the violent water electrolysis or gas evolution, and subsequently the quality of the deposited PEI layer was excellent with the RMS roughness in 15∼35 nm. The thermally transformation of q-PEI to PEI was confirmed using FT-IR. Based on the electro-rheological theory of suspension drops under electrical potential, the key operation parameters of EPD, i.e., deposition time and applied voltage, were thoroughly investigated by measuring the thickness, surface roughness, and cross-section images of specimens. This work demonstrated that the low-voltage EPD could minimize the gas evolution rates and, thus, provide a high-quality PEI coating on metal surfaces without pinholes, voids, or delaminated areas within a reasonable span of EPD processing time.