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This paper presents modeling and simulation of spring-mass damper system for quarter car in the Simulink environment. The simulations in this research have been carried out by using the Simulink of Matlab. The parameters in the simulation model for the suspension system under study include car body mass, wheel mass, spring and damping elements of shock absorber, and tire. A road disturbance profile comprising a combination of two sinusoidal curves is modeled. Controllers that are used in this study are the proposed fuzzy logic controller. The purpose of this research is to improve vehicle comfort using the Fuzzy Logic Controller (FLC). The simulation results of the system perform well fulfill the minimum percentage requirements and fast stability time, provide good leveling of stability and ride comfort.

This paper presents a prediction of cutting temperature in turning process, using a continuous cutting model of Johnson-Cook (J-C). An method to predict the temperature distribution in orthogonal cutting is based on the constituent model of various material and the mechanics of their cutting process. In this method, the average temperature at the primary shear zone (PSZ) and the secondary shear zone (SSZ) were determined for various materials, based on a constitutive model and a chip-formation model using measurements of cutting force and chip thicknes. The J-C model constants were taken from Hopkinson pressure bar tests. Cutting conditions, cutting forces and chip thickness were used to predict shear stress. Experimental cutting heat results with the same cutting parameters using the minimum lubrication method (MQL) were recorded through the Testo-871 thermal camera. The thermal distribution results between the two methods has a difference in value, as well as distribution. From the difference, we have analyzed some of the causes, finding the effect of the minimum quantity lubrication parameters on the difference.

This study presents conducted heat simulations and experimental jointing flat-plate of aluminum alloy 6061 and SUS 304. Temperature is simulated by the COMSOL software in three states: (1) Preheat the Friction Stir Welding (FSW) by TIG welding, (2) Thermal contact resistance between Aluminium and steel, and (3) The welding process using stiring friction is simulated. The simulations intended to predicting the temperature which is used for preheat and welding process to ensuring the required solid-state welding. The temperature is also determined and checked by a thermal imager comparing with simulation results. Besides, the results of tensile strength is carried out. The Box - Behnken method is used to identify the relationship between the welding parameters (rotation, speed and offset), temperature and tensile strength. The maximum tensile strength is 77% compared to the strength of aluminum alloy. The optimal set of parameters for the process is n = 676 rpm, v = 46 mm / min and x = 0.6 mm. The optimizing welding parameters to achieving good quality of welding process are described. SEM images to determine some properties of welding materials. This is also the basis for initial research to identify some defects in welding of two different materials (IMC thickness and interconnected pores) and the cause of these defects.

According to petrophysical and geophysical data, the depositional facies of E Oligocene are determined. Furthermore, the correlation lines between wells and the seismic line also created for confirming Oligocene E distribution in Cuu Long basin. Using appropriate methods such as petrophysical curves, geophysical characteristics, interpretation of gross depositional environment as well as mapping of seismic attributes for sub-sequence Oligocene E upper and E lower in Southeast area, results of prediction the sand distribution in Oligocene E upper and E lower sub-sequence, factors effect to porosity-permeability preservation of E sand reservoirs in Southeast area, Cuu Long basin and oil-gas industry flow-producing possibility in varied sedimentary facies were reported in this paper. The E Oligocene sedimentary distributes in a large area with hydrocarbon accumulations along the Southeast margin Cuu Long basin in relation with the existence of half-grabens along Con Son swell, in which formation rocks consist of varying grain size, mainly sandstone interbeds by siltstone and shale stone. A bitum shale layer of 20÷70 m thickness exits to play the role of a shield to maintain a much higher effective porosity of the reservoir section than usual (up to 18%). In the area, there are two sandstone reservoirs of excellent quality at 2,600÷2,700 mMD and 3,000÷3,400 mMD depths. In order to determine the oil and gas potential of the target, petroleum systems in exploration activities must carefully be evaluated, especially looking for stratigraphic traps, and the reservoir modeling should be modified accurately.

Friction stir welding exploits its solid-state process behavior to join aluminum to steel, which differs in thermal and mechanical properties, and where a combination of these metallic alloys by fusion welding prompts a deleterious reaction as a result of the melting and resolidification phases. Recently, hybrid techniques have been employed in FSW for several materials and alloys, particularly for steel–steel joining. These methods are generally aimed to pre-heat the steel plate materials. This study presents conducted heat simulations and experimental jointing flat-plate of aluminum alloy 6061 and SUS 304. Temperature is simulated by the COMSOL software in three states: (1) Preheat the Friction Stir Welding (FSW) by TIG welding, (2) Thermal contact resistance between aluminum and steel, and (3) The welding process using stirring friction is simulated. The simulations intended to predict the temperature, which is used for the preheating and welding process to ensuring the required solid-state welding. The temperature is also determined and checked by a thermal imager comparing with simulation results. Besides, the results of tensile strength are carried out. The Box - Behnken method is used to identify the relationship between the welding parameters (rotation, speed, and offset), temperature, and tensile strength. The maximum tensile strength is 77% compared to the strength of the aluminum alloy. The optimal set of parameters for the process is n = 676 rpm, v = 46 mm / min and x = 0.6 mm. The optimizing welding parameters to achieving a good quality of the welding process are described. SEM images to determine some properties of welding materials. This is also the basis for initial research to identify some defects in the welding of two different materials (IMC thickness and interconnected pores) and the cause of these defects.

This paper describes the design and fabrication of a wave flume and associated equipment. The water wave generation by a triangle wedge is examined in this paper. Wave flume is fabricated by a concrete flume, which is 0.75-meter-wide, 1.3-meter-tall, and 11 meters long. One side of the flume is made of concrete, and the other side is made of clear mica sheets for observe the water wave profile. Wave flume is equipped with a triangle wedge located at one end of the wave flume, and this triangle wedge can be move along the rail of the wave flume. The passive wave absorber, which is made of honeycomb, which is located at the other end of the wave flume for absorbing energy waves generated from the wavemaker. The wedge is controlled by a desktop computer through Matlab software. The wedge can be controlled move up and down at a prescribed speed and oscillation amplitude corresponding to the desired wave height and wave frequency. At the middle flume is equipped microlaser distance sensor, which provides the data-logging capability. The microlaser distance sensor can collect wave height and wave period through a small ball, which is motioned in the tube, which is assembled on the water surface, and the small ball is very slight to avoid kinetic inertia energy. At the wavemaker is equipped with an Eccentricity Sensor, which is used to measure the wedge position to feedback for a desktop computer. Wave flume can generate the largest waves are about 0.2 meter high, a period about 1 second, and a wavelength of about 1.5 meters. The waves generated by an oscillating wedge have been measured, analyzed to consider the generated wave energy.

Based on the number of previous studies, this study aims to investigate the effects of process parameters of an Electrochemical Machining process, which are electrolyte concentration, the voltage applied to the machine, feed rate of the electrode, and Inter-Electrode Gap between tool and workpiece. Aluminum samples of 25 mm diameter x 25 mm height and 30mm diameter x 25mm height of the tool is made up of copper with a circular cross-section with 2 mm internal hole. The design of the system is based on the Taguchi method. Here, the signal-to-noise (S/N) model, the analysis of variance (ANOVA) and regression analyses are applied to determine optimal levels and to investigate the effects of these parameters on surface quality. Finally, the experiments that use the optimal levels of machining parameters are conducted to verify the effects of the process parameters on the surface quality of the products. The results pointed out a set of optimal parameters of the ECM process. The Inter-Electrode Gap between the tool and workpiece has extremely effected on these Material Removal rates and surface roughness. The Material Removal Rate increases with diseases in Inter-Electrode Gap, and Ra diseases with diseases in Inter-Electrode Gap. The experimental results show that maximum Material Removal Rate has obtained with electrolyte concentration at 100 g/l, feed rate at 0.0375 mm/min, the voltage at 15V, and Inter-Electrode Gap at 0.5mm. The minimum Ra has obtained with electrolyte concentration at 80 g/l, feed rate at 0.0468 mm/min, the voltage at 10V, and Inter-Electrode Gap at 0.5mm. This result has led to need studies on these parameters in Electrochemical Machining, which are improving productivities and surface roughness of the products.

The effects of cutting fluids to health, environment, productivity, and quality in machining operations have been discussed. MQL is a green technology that is gradually applied in mechanical processing. The article has introduced about MQL cooling lubrication method in mechanical processing. Some previous research results have been made to clarify the meaning of this method. In addition, the comparison of the outputs of MQL, dry, and wet methods has also been shown to show the effectiveness of the MQL method. Then, based on the MQL equipment being used at Tran Dai Nghia University, the authors designed the experiment to evaluate the impact of MQL parameters on the process outputs. Machining and optimization of that parameter. This paper presents the MQL parameters optimization approach in which the multi-response outputs based on Taguchi's L9 orthogonal array method is used. During the turning AISI-1045 steel, the cutting temperature, the maximum of tool wear, and the surface roughness were measured. The MQL parameters, which are the ratio of soluble lubricant and water, pressure of spray head, the flow volume of the emulsion was simultaneously optimized by taking the multi-response outputs using Taguchi based grey relational analysis (GRA) into consideration. In turning experiments, three different flow volume of emulsion Q (40, 60, 80 ml/h), three different levels pressure of spray head P (3, 5, 7 bar) and three different levels ratio of soluble lubricant and water R (4, 6, 8%) were used. Here, three mathematical models were created using response surface regression methodology. The experiments had been done to investigate the effect of the MQL parameters to the turning process. As a result, the set of optimal MQL parameters had been pointed out to simultaneously minimize the cutting temperature, the tool wear, and surface roughness. The Flow volume of emulsion 80 ml/h, Pressure of spray head 7 bar, Ratio of soluble lubricant, and water 6% was observed to be the most effective.

The aim of this paper is to design, fabricate and control a novel Linear Magnetic Actuator (LMA) for applications such as active magnetic bearing systems to deal with vibration problems in rotating machines. This LMA actuator contains a moving body named ‘mover’ and three driving parts to drive the mover. Firstly, experiments have been conducted on the LMA to derive its mathematical model in order to investigate the generated electro-magnetic force as well as further research. The modeling result in a comparison with the actual system performance show that the electro-magnetic force varied symmetrically with the mover motion defined by the applied current. Secondly, an advanced trajectory controller named online tuning fuzzy PID controller has been designed for the LMA to improve the working performance. Finally, real-time experiments have been carried out to evaluate the tracking performance of the designed LMA control system. The results prove that the LMA driven by the proposed controller could track the desired trajectories with high accuracy.

In this paper, a novel magnetic actuator named Linear Magnetic Actuator (LMA) is proposed, designed and fabricated for applications such as active magnetic bearing systems to deal with vibration problems in rotating machines. The LMA actuator is constructed from a moving body called ‘mover’ and three driving parts which drive the mover. Real-time experiments on the LMA have been conducted to derive a mathematical model for this actuator to investigate the generated electro-magnetic force as well as further research. The modeling results in a comparison with the actual performance show that the electro-magnetic force varied symmetrically with the mover motion defined by the applied current. Furthermore, an advanced trajectory controller — online tuning fuzzy PID controller has been designed for the LMA in order to improve the working performance. Finally, real-time experiments have been carried out to investigate the tracking performance of the designed LMA control system. The experimental results prove that the LMA driven by the proposed controller could track the desired trajectories with high accuracy.

Hydraulic systems play an important role in modern industry owing to the fact that hydraulic actuator systems have many advantages over other technologies with electric motors, high durability, and the ability to produce large force at high speeds. Therefore, the hydraulic actuator has a wide range of application fields such as hydraulic pressing machines, moulding technology, etc. where controlled forces or pressures with high accuracy and fast response are the most significant demands. Consequently, many hybrid actuator models have been developed for research on how to control forces or pressures with the best results. The current paper presents a new kind of hydraulic load simulator for conducting performance and stability tests for control forces of hydraulic hybrid systems. In the dynamic loading process, disturbance makes the control performance (such as stability, frequency response, loading sensitivity, etc.) decrease or turn bad. In order to improve the control performance of a loading system and to eliminate or reduce the disturbance, an online self-tuning fuzzy proportional—integral—derivative (PID) controller is designed. Experiments are carried out to evaluate the effectiveness of the proposed control method applied for hydraulic systems with varied external disturbance as in real working conditions.

An enhancement of the dynamic behavior of the rotating shaft work at high operating speed by using Squeeze film dampers (SFDs) has been becoming an important part in changing the dynamic characteristics of machinery. In this paper, a new type Controllable Squeeze Film Damper (CSFD) is proposed, designed and fabricated by changing the clearance of the thin-film fluid. Both of the critical speed and critical amplitude are reduced with the suitable damping coefficient. A novel Linear Magnetic Actuator (LMA) is investigated and used to move the outer damper of the CSFD. The experiment results illustrate basically the concept of electromagnetic effect as well as the interaction force between electromagnet and permanent magnet. Furthermore, the PID and advanced (a self-tuning fuzzy PID) controllers are subsequently applied to controlling exactly the position of a novel LMA. The experimental results reveal that the vibration behavior of rotor dynamic response is affected effectively by changes of the clearance.

This paper describes work on isolation of vibration related engine by a hydraulic engine mount with controllable area of inertia track. Automotive engine mounts are required to constrain motion of engine shake resulting from low-frequency road input of shock excitation and also to isolate noise and vibration generated by the engine with unbalanced disturbance at the high frequency range. The property of the mount depends on vibration amplitude and excitation frequency, which means that the excitation amplitude is large in low excitation frequency range and small in high frequency range. In this paper, theoretical works with new model of the mount to isolate vibrations related engine were conducted by an optimal algorithm to control area of inertia track under shock and multi-signal force excitation is considered. With this research show clearly volumetric stiffness of the mount is greatly changed according to the changed area of the inertia track. Therefore, when the area of the inertia track is tuned, the transmissibility of the mount is effectively reduced.