Uji Modifikasi Komponen dan Sistem Pengapian Yamaha 5D9 Terhadap Emisi Gas Buang dan Konsumsi Bahan Bakar

This study aims to determine the effect of modification of components and ignition system on exhaust emissions and fuel consumption on a Yamaha 5D9 motorcycle. The research method used is a case study. The tool used to perform the emission test is a Gas Analyzer type SUKYOUNG SYGA-401 and fuel consumption is measured using a measuring cup. The results showed 1) exhaust gas emissions on the modification of the components of the piston, valve, and ignition system, namely CO 5.76%, CO2 1.6%, and O2 18.09%. 2) fuel consumption increases at each engine speed of 1000 rpm = 100ml, 2000 rpm = 200ml, and 4000 rpm = 400ml, 3) the distance traveled increases at each engine speed of 1000 rpm = 1.9 km, 2000 rpm = 3, 1 km, and 4000 rpm = 4.6 km. Penelitian ini betujuan untuk mengetahui pengaruh modifikasi komponen dan sistem pengapian terhadap emisi gas buang dan konsumsi bahan bakar pada sepeda motor Yamaha 5D9. Metode penelitian yang digunakan menggunakan case study. Alat yang digunakan untuk melakukan uji emisi adalah Gas Analyzer type SUKYOUNG SYGA-401 dan konsumsi bahan bakar diukur menggunakan gelas ukur. Hasil penelitian menunjukan tiga hal, pertama emisi gas buang pada modifikasi komponen piston, katup, dan sistem pengapian yaitu CO 5,76%, CO2 1,6%, dan O2 18,09%. Kedua, konsumsi bahan bakar meningkat pada setiap putaran mesin 1000 rpm = 100ml, 2000 rpm = 200ml, dan 4000 rpm = 400ml. Dan terakhir, jarak yang ditempuh meningkat pada setiap putaran mesin yaitu 1000 rpm = 1,9 km, 2000 rpm = 3,1 km, dan 4000 rpm =4,6km.

Numerical Methodology for Determining the Energy Losses in Auxiliary Systems and Friction Processes Applied to Low Displacement Diesel Engines

The problem of climate change and the reduction of fossil fuels has motivated the development of research focused on improving the efficiency of internal combustion engines. This research proposes a methodology based on mathematical models to determine the energy losses caused by auxiliary systems and friction processes in the engine. Therefore, models are proposed for calculating the energy losses in fuel injection, lubrication, and cooling system. In the same way, models are proposed for the energy losses due to friction in the piston, valve train, and bearings. Experimental tests are carried out on a single-cylinder diesel engine under different operating conditions to validate the proposed models. The results showed that the energy losses of the fuel injection, lubrication, and coolant system are equal to 0.61%, 0.30%, and 0.31% of the chemical energy of the injected fuel. In the case of the energy losses by friction processes, the piston, valve train, and bearings represent 5.47%, 1.34%, and 1.85% of the fuel energy, respectively. Additionally, the proposed model allows estimating the minimum lubrication film present in the piston, valve train, and bearings, which in the particular case of the present study were 0.63 µm, 0.10 µm, and 0.57 µm, respectively. In general, the methodology developed in the present work stands as a robust tool to evaluate the modifications and/or designs of auxiliary systems and friction processes to reduce the energy losses and protect the system from wear caused by lubrication problems. Additionally, the methodology allows evaluating the effect of different types of fuels on the lubrication conditions of the piston and the crankshaft bearings.

A Concentric Design of a Bypass Magnetorheological Fluid Damper with a Serpentine Flux Valve

This work presents a new concentric design structure of a bypass magnetorheological (MR) damper with a serpentine flux valve type. In this design, the serpentine valve is installed not in the middle of the piston but on the bypass channel of the damper. However, to make it less bulky, the location of the valve installation is chosen to be in line with the cylinder axis, which is different from the common configuration of the bypass damper. With the proposed design concept, the performance flexibility of the bypass configuration and the compactness of the piston valve configuration can be accomplished. In this study, these benefits were demonstrated by firstly deriving an analytical model of the proposed MR damper focusing on the bypass concentric valve structure, which is vital in determining the damping force characteristics. The prototype of MR damper was also fabricated and characterized using the dynamic test machine. The simulation results show that the damping force could be adjusted from 20 N in the off-state to around 600 N in the on-state with 0.3 A of excitation current. In the experiments, during low piston velocity measurement, the on-state results from the simulation were generally in good agreement with the experimental results. However, with the increase in piston velocity, the deviation between the simulation and the experiment gets higher. The deviations are most probably due to seal frictions that were not accounted for in the model. The seal friction is probably dominant as the seals in the prototype need to be prepared for handling higher fluid pressure. As a result, the frictions are quite prevalent and significantly affect the measured off-state damping forces as well, where it was recorded ten times higher than the predicted values from the model. Nevertheless, although there were deviations, the dynamic range of the concentric bypass structure is still 1.5 times higher than the conventional structure and the new structure can be potentially explored more to achieve an improved MR damper design.

Assessment of the Dynamics Flow Field of Port Plate Pair of an Axial Piston Pump

This paper aims at studying the dynamic fluid evolution process of port plate pair of an axial piston pump. First of all, The Renormalization Group k-ε model (RNG k-ε model) is implemented to simulate the dynamic flow distribution and forecast the evolution of the internal vortex structure inside the valve plate chamber with different speeds of pistons and velocities of inlet fluid by using computational fluid dynamics software. Then, an equivalent amplification test model of a piston-valve plate is built up based on Reynolds similarity theory; the flow state of the piston-valve plate flow field is observed applied the particle image velocimetry (PIV) measuring technique. The resulting uniformity of numerical simulation and PIV measurement verifies that the RNG k-ε model can achieve high-precision prediction for the vortex structure inside the valve plate chamber. Through analysis of velocity contours and streamlines of the flow field, it can be found that vortices with different scales, strengths and positions will occur during the process of fluid distribution, and the scale and strength of the vortex inside the valve plate chamber will be reduced with the increase of the piston’s moving speed, so the energy loss is also reduced and the efficiency is improved.

Designing of a Twin Tube Shock Absorber

Reverse engineering has become the one of the most relevant concepts in modern design doctrines. Advances in technology demand shorter lead time in the overall product development stage, especially in the automobile sector. Hence as a study in reverse engineering, the author has reverse engineered a twin tube shock absorber. The process involved the obtaining of subassemblies of the damper mechanism to generate a 3D CAD model of the damper in PTC CREO 2.0. The model was used to conduct static structural and CFD analysis of the same using ANSYS 15.0 Workbench. The data obtained was used as the datum for the design modifications and performance enhancement of the part. It was seen that the design of the piston valve was optimum hence modifications to the base valve were done. Following the generation of the datum, similar analyses were conducted on the modified assemblies. The results were compared to the datum for the selection of the most appropriate design. Four designs are analyzed and compared with the datum and the set with four orifices in the valve disk was found to be optimum.

Estimation for Variation of the Damping Force Induced by the Expansive Movement of Shock Absorber

In this paper, the damping force loci of a twin tube shock absorber were estimated by using the empirical data. The variation of the damping force was investigated for movements of piston such as the expansion. The relationship between the piston velocity and the damping force were estimated by using the empirical data of four different conditions of coil spring turns. Also the relationship between the coil spring turns and the damping force were estimated by using the empirical data of four different piston velocities. Based on the experiment results, the estimated damping force variation functions provide the physical information of the components of the main piston valve system to save the manufacturing time and cost for the shock absorber

Research for Application of Save Energy Piston Valve for Water Pump Balance Control

This paper introduces new type of save energy piston valve for water pump balance control, which is save energy efficiency expert. This piston valve is designed by pneumatic theory, and drive power is delivered by air compressor or pressure air source in waterworks. Pressure air is lead into cavity of piston valve by transfer action of “two positions and five channels ” electromagnetic valve, then piston drive valve to open or close water pump. This piston valve has followed functions such as balance control action, avoiding refluence, zero flow open and close, accidental power stop for water hammer and son on. Application of this piston valve had proved saving energy to 3%.