A review of design and modeling of magnetorheological valve

Following recent rapid development of researches in utilizing Magnetorheological (MR) fluid, a smart material that can be magnetically controlled to change its apparent viscosity instantaneously, a lot of applications have been established to exploit the benefits and advantages of using the MR fluid. One of the most important applications for MR fluid in devices is the MR valve, where it uses the popular flow or valve mode among the available working modes for MR fluid. As such, MR valve is widely applied in a lot of hydraulic actuation and vibration reduction devices, among them are dampers, actuators and shock absorbers. This paper presents a review on MR valve, discusses on several design configurations and the mathematical modeling for the MR valve. Therefore, this review paper classifies the MR valve based on the coil configuration and geometrical arrangement of the valve, and focusing on four different mathematical models for MR valve: Bingham plastic, Herschel-Bulkley, bi-viscous and Herschel-Bulkley with preyield viscosity (HBPV) models for calculating yield stress and pressure drop in the MR valve. Design challenges and opportunities for application of MR fluid and MR valve are also highlighted in this review. Hopefully, this review paper can provide basic knowledge on design and modeling of MR valve, complementing other reviews on MR fluid, its applications and technologies

Design and dynamic stiffness evaluation of magnetorheological elastomer bushing using FEMM and dynamic testing machine

This research presents a simulation study on electromagnetic behaviour of magnetic flux density distribution in a magnetorheological elastomer (MRE) bushing. The design concept of MRE bushing is based on the design of the bushing used in the conventional car, only the natural rubber is being replaced by the MRE compound. Furthermore, the electromagnetic simulations were conducted by using Finite Element Method Magnetics (FEMM) software where the main aim is for more magnetic flux density in the MRE, which indicates better performances for MRE bushing in this study. The best configuration of the MRE bushing for this study is using single coil, magnetic material for all parts except for coil bobbin, and the thickness of ring plate of 4 mm, which yield the highest magnetic flux density of 0.205 T. By using this configuration, the dynamic stiffness of this MRE bushing is ranging from 2259.13 N/mm to 2671.06 N/mm with the applied currents of 0.5 A to 2.5 A and frequencies from 1 Hz to 15 Hz. All in all, the optimized configurations improve the performance of MRE bushing remarkably

Hazard control management on optimization layout of vent stack at offshore platform

The flaring is a normal practice in the oil and gas industry to achieve a safe and reliable process during the emergency situation. This situation is a routine practice for oil and gas production by controlled burning of natural gas. The burning process can cause hazards by explosion or at the very least surrounding environment will be affected by heat radiation during vent stack burning operation. Hence, investigation of the gas flaring produced by the vent stack is needed to tackle these problems. This paper presents designing a safe vent stack position in the limited space of oil and gas platform with considered the heat radiation produced by the vent stack. The simulation will be done by using flaresim software to predict the heat contour, heat radiation, and gas dispersion. The results proved that the optimal position of vent stack with water shield gives a better heat radiation

Technology application in logistic and supply chain management

Technology of the modern era has brought an overhaul to the supply chain management and logistics systems completely. With apps that enable easy tracking of the product and supply distribution, even small businesses are flourishing exponentially. This paper discusses the literature review on the applications of these systems, concerning technological advancements, in operational and supply chain management strategies and how managers implement these systems using technology and modern applications. The introduction of computers and machine intelligence has changed the way of the organization doing the supply chain management. From robotic packaging of products to drone delivery systems, artificial and augmented intelligence is the future of logistics as opposed to the traditional supply chain management, where it was based upon physical delivery systems and vendors selling the product or franchises and distributions among markets for a certain product. The implications and negative aspects of technology with the inclusion of risks affiliated with Web 2.0 type cloud servers are also discussed in depth

Design of magnetorheological valve using serpentine flux path method

Magnetorheological (MR) valve is widely applied in a lot of applications that utilizes the flow mode, which is one of the working modes available for MR fluid devices. This paper introduces the serpentine flux path method in an MR valve, whereby using this method it can help to increase the effective region of the valve. The magnetic flux is guided into the annular gap of the valve, as the magnetic flux can be weaved by alternating the magnetic and non-magnetic materials. The method is simulated using Finite Element Method Magnetics to see the effects of weaving steps and thicknesses of non-magnetic materials to the magnetic flux distribution and pressure drop change in the valve. The results show that MR effective region can be increased with the serpentine flux path method, and the additional steps and thicknesses of non-magnetic materials help to further increase the pressure drops within the valve

Study on stability and control analysis for cascade hybrid electric vehicle

This research contributes in studying the configuration of hybrid electric vehicles (HEV) which have been developed and used in modern days. The hybrid topologies that combine multiple power sources with motive force to increase the driving function are also studied. The objectives of this study are to determine the time and frequency domain equations that characterize the relationship between the input, output, and state variables for the forward path of car motive dynamics system. In this paper, a block diagram of HEV forward path with feedback signal and controller gain was proposed while assuming the motor to be an armature controlled direct current. The transfer function and state-space were developed and its stability was analyzed and used to describe the car motive dynamics. Matlab and Simulink were used to simulate the system. The simulation results showed the state-space and transfer function of HEV system with excess motive force of 2650 N. The results clearly indicated that the designed controllers were able to improve the steady-state, transient analysis, and desired output. It was also demonstrated that the step input with proportional-integral-derivative controller was efficient in term of the best transient response with zero steady-state error. While, bode plot graph illustrated that the system was inherently stable

Intrinsic apparent viscosity and rheological properties of magnetorheological grease with dilution oils

In this study, the principal rheological properties of the magnetorheological grease (MRG) is experimentally investigated with various types and percentages of dilution oils. The stability in terms of oil separation and rheological properties of the natural plant-based dilution oil; castor oil was compared with petroleum-based; kerosene and hydraulic oils. Several samples of MRGs with different types and ratios of dilution oils were prepared by mixing spherical carbonyl iron (CI) particles and grease using mechanical stirrer. The rheological test was performed under rotational mode of shear rheometer by changing the magnetic fields from 0 to 0.7 T at room temperature condition. The results showed that the apparent viscosity of the dilution oils of kerosene has the lowest apparent viscosity followed by castor and hydraulic oils. It has been observed that by addition of dilution oils more than 10 wt% has reduced the stability of the samples. It is also noted that the increment of dilution oils percentages in MRGs have insignificant effect towards linear viscoelastic (LVE) region. This fact indicated that the improvement of the rheological properties was dependent on the initial viscosity as well as optimum percentage of the dilution oils utilized in the MRG suspension without visibility of the oil separation. In addition, the comparison of the MRG performance in terms of yield stress between different types and percentages of dilution oils was evaluated and discussed in detail

The field-dependent rheological properties of plate-like carbonyl iron particle-based magnetorheological elastomers

This paper investigated the rheological properties of a novel magnetorheological elastomer (MRE) with plate-like carbonyl iron particles (CIPs) as magnetic particles. MRE samples with different shape of CIPs; plate-like (MRE-P) and spherical-like (MRE-S), were prepared. The current work further highlights the effects of varying curing magnetic field towards the rheological properties. X-ray diffraction and magnetic properties analysis were carried out to observe not only the surface morphology of the CIPs but also the cross-section of CIPs in the MRE samples. Rheological properties such as strain amplitude, frequency, and magnetic field sweep test were measured using a rotational rheometer. The MRE-P samples demonstrated higher storage modulus and the loss factor lower than MRE-S. Besides that, the MR effect of MRE-P samples is slightly lower than that of MRE-S correspond to 114% and 137%, respectively

In situ stannous reagent generator (SRG): An alternative hexavalent chromium treatment technology in drinking water industry

Access to safe drinking water is a basic necessity for human health. Rock and soil are rich sources of chromium, a metal that is present naturally. Chromium commonly exists in two oxidation states: trivalent chromium (chromium-3, Cr (III), Cr3+) and hexavalent chromium (chromium-6, Cr (VI), Cr6+), in the natural environment, as well as in the water treatment and distribution systems. While Cr (III) is an essential nutrient for humans, Cr (VI) is a dangerous pollutant that can build up in both the environment and the tissues of living things. The Cr (VI) treatment traditionally uses techniques such as electrodialysis reversal, ion exchange, electrochemical, reduction, coagulation, oxidation and filtration systems. Chemical costs, secondary waste production, and unintentional regeneration of Cr (VI) after treatment are difficulties with standard Cr (VI) treatment. In order to remediate Cr (VI) in raw water, this study looks into the in-situ stannous reagent generator (SRG) package as a potential disruptive green technology. SRG was able to reduce roughly 40 parts per billion (ppb) of Cr (VI) to below 1.0 ppb after being installed on a raw water source site for a 10-day trial period. The In Situ SRG technology provides an efficient and safe method for treating Cr (VI) in drinking water, reduces the health risks associated with Cr (VI) exposure by converting it to a less toxic form and reduces chemical handling risks. Reductive Cr (VI) treatment technologies based on the use of stannous tin hold tremendous promise in the future to overcome green-house gas (GHG) emissions and other anthropogenic environmental change, in addition to effectively reducing Cr (VI) in drinking water to the permissible limits and high energy cost challenges. In Situ Stannous Reagent Generator (SRG) technology is designed to convert Cr (VI) to its less toxic trivalent form, Cr (III), which is less harmful and easier to remove from water

Characterization of morphological and rheological properties of rigid magnetorheological foams via in situ fabrication method

This paper presents material characteristics of a rigid magnetorheological (MR) foam that comprises polyurethane foam matrix and carbonyl iron particles (CIPs). Three different samples of MR foams are prepared by changing the concentration of CIPs (0, 35, and 70 g) in isotropic condition. In-depth characterization on the morphological properties, the field-dependent rheological behavior in terms of linear viscoelastic region and storage modulus, and the off-state sound absorption properties are then experimentally investigated. In the morphological observation, it is seen from the fluorescence micrographs that MR foam consists of open pore structure and the average size of the pores is decreased with the increment in CIPs content. In the rheological test of MR foam, it is identified that MR foam with the addition of 70 g of CIPs to the total of polyol and isocyanates (100 g) can enhance the storage modulus up to 112% compared with MR foam without CIPs. In the meantime, from the acoustic absorption test, it is shown that the maximum peaks of sound absorption coefficient (SAC) are shifted to the low frequency and the SAC is increased up to 229% due to the decrement in the pores size and increment in the storage modulus. The results achieved from this material characterization of MR foam provide useful guidelines for the development of new type smart materials associated with MR fluids and for the findings of appropriate applications which require controllability of both the stiffness and acoustic properties