Experimental Study on the Effect of Waste Valve Load and the Volume of Air Chamber on the Performance of the Hydraulic Ram Pump (Hydram) to Water the Paddy Field in Pakandangan, Padang Pariaman Regency

This 2019 DIPA Grand’s research designed and fabricated the size of hydraulic ram (hydram) pump utilized in Pakandangan, Padang Pariaman Regency. There is a water source in this area which has not been functioned adequately to irrigate the paddy field of 10 hectares due to the location of the paddy field which is higher than the water source. However, the use of designed hydram pump has no been maximized as the pump’s optimal performance was not determined yet. Therefore, a hydram pump was designed by varying the load of waste valve in the weight of 400 g, 600 g, 800 g, 1,000 g, and 1,200 gr. It was also varied in the volume of the chamber when the pump operated which were 4.86 lt, 5.76 lt, 6.48 lt, 7.29 lt, and 8.1lt. The height (Hd) of the inlet pipe was 1 m, and the lift height (Hs) of the outlet pipe was 5 m. The results obtained from Pump performance increases with increasing cylinder volume. The increase in the load of the exhaust valve volume of the tube remains a significant decrease. Hydram pump performance occurs at a load of 400 g with a tube volume of 8.1 l with an efficiency of 53%

Computational studies of the influence of variable valve timing on the performance of a gas engine with Miller’s thermodynamic cycle

Current development trends in the field of internal combustion engines aim at regulating all processes of the engine and individual units. A converted diesel to gas engine with Miller thermodynamic cycle is more energy efficient at partial loads than a gas engine with Otto thermodynamic cycle. The Miller cycle engine with variable valve timing and valve lift has been investigated to improve performance and energy efficiency across the load range. The aim of the work is to study the influence of the displacement of the valve timing phases of the intake and exhaust camshafts and the valve lift height on the performance of the gas engine with the Miller cycle. Computer modelling was based on data obtained from the full-scale experiment on the gas engine with the Miller thermodynamic cycle.

The Numerical Simulation of Uplifted Street Canyon On Flow Field Structure And Pollutant Diffusion

The flow field structure, pollutant concentration distribution and dimensionless concentration evolution of uplifted street canyon has been analyzed in this study. Different from the ideal street canyon, the pollutant concentration distribution of the uplifting street canyon is higher at the bottom, lower at the top, higher at the windward side and lower at the leeward side. The total pollutant concentration (TPC) generally decreases with the increase of leeward building lifting height while the lift height increases with the same total building height or the total building height increases with increase in the lifting height. It is beneficial to the pollutant emission of in street canyon. On the contrary, the TPC increases when the total building height increases with the same lift height. The main reason is that the vertical length of the vortex increases, which is more difficult for pollutants to be discharged from the street canyon.

RESEARCH OF DYNAMIC STABILITY OF THE MACHINE-TRACTOR UNIT ON THE VIRTUAL STAND

The questions of studying the dynamic stability of machine-tractor unit by the methods of multi-body dynamics (MBD) are considered. The study used a virtual stand created in CAD SolidWorks and CAE application SolidWorks Motion. It simulated the movement of the machine-tractor unit on the basis of the MTZ-82.1 tractor equipped with mounted modular implements. The motion surface has four different types of obstacles located in series in separate sections. To analyze the stages of the machine-tractor unit movement, we used the parameter of the lift height of the geometric center of each of the wheels above the supporting surface and the fact of the unit rollover. He showed that overcoming a single linear, single sequential and group linear obstacles at a speed of 3.22 m/s occurs without loss of stability. Only when overcoming a group sequential obstacle, significant fluctuations in the tractor frame are observed, however, due to the balancing suspension of the front wheels, they do not always lead to the rollover of the unit. In the future, using the developed virtual stand, it is possible to conduct studies of the dynamic stability of various configurations of the machine-tractor unit. In addition to the MTZ 82.1 tractor, models of other tractors can be used. It is also possible to change the geometry of obstacles, the angles of inclination of the supporting surface, speed mode, contact parameters, etc.

Development of variable-configuration wheeled driving system for enhancing the obstacle-crossing ability of unmanned vehicles

A variable-configuration wheeled driving system is proposed to improve the obstacle-crossing abilities of unmanned vehicles. The effects of the wheel load on the wheels’ obstacle-crossing abilities are analysed using statics theory. Similarly, the effects of the suspension’s stiffness and the adhesion coefficient on the vehicle’s obstacle-crossing ability are analysed. Numerical calculation results show that a higher wheel lift height leads to improved obstacle-crossing abilities. A strategy to adjust the system configuration during obstacle crossing is designed with the wheel lift height acting as the optimisation target. The variable-configuration strategy is verified and the optimal adjustment of the middle axle is determined through simulations. An obstacle-crossing experiment shows that a vehicle can cross a 1-m step obstacle when the proposed variable-configuration strategy is applied. The obstacle-crossing ability of the unmanned vehicle can thus be greatly enhanced.

Characterization of the effects of a plasma injector driven by AC dielectric barrier discharge on ethylene-air diffusion flame structure

A dielectric barrier discharge plasma controlled diffusion flame experimental system was built based on the designed coaxial swirling plasma injector. The air plasma was generated within the annulus gap of the injector by alternating current dielectric barrier discharge. The discharge characteristics and power of plasma injector under different actuation intensities and air flowrates were measured. Through the measurement techniques, such as schlieren imaging, broadband chemiluminescence image and CH* chemiluminescence, the effect and mechanism of plasma on ethylene-air normal diffusive jet and flame was explored. The results showed that a large number of filamentary discharge channels are formed in air plasma. The increase of air flowrates weakened the intensity of discharge to a certain extent. The induced jet generated by the plasma can short the laminar length of the ethylene-air jet, accelerate the transition of the flow jet, enhance the turbulence and the mixing of the fuel and the oxidizer. The higher the actuation intensity, the shorter distance of the cold jet transition zone, the higher the jet turbulence. Depending on the aerodynamic and kinetic effects, plasma can improve the stability of ethylene-air diffusive flame and reduce the lift height between the flame root and injector. The plasma can also expand the flammability limit of ethylene-air flame and make the flame ignited under some conditions that could not be. In addition, the CH* chemiluminescence shows that, in a certain range of discharge voltage, the heat release distribution can be changed on both sides of the flame, and its representative length are generally reduced as the voltage rises. On the contrary, the overtop voltage could lead to a decrease of flame heat release.

Electronic Design of a Cotton Harvester Yield Monitor Calibration System

Several yield monitors are available for use on cotton harvesters, but none are able to maintain yield measurement accuracy across cultivars and field conditions that vary spatially and/or temporally. Thus, the utility of yield monitors as tools for on-farm research is limited unless steps are taken to calibrate the systems as cultivars and conditions change. This technical note details the electronic system design for a harvester-based yield monitor calibration system for basket-type cotton strippers. The system was based upon the use of pressure sensors to measure the weight of the basket by monitoring the static pressure in the hydraulic lift cylinder circuit. To ensure accurate weighing, the system automatically lifted the basket to a target lift height, allowed the basket time to settle, then weighed the contents of the basket. The software running the system was split into two parts that were run on an embedded low-level micro-controller and a mobile computer located in the harvester cab. The system was field tested under commercial conditions and found to measure basket load weights within 2.5% of the reference scale. As such, the system was proven to be capable of providing an on-board auto-correction to a yield monitor for use in multi-variety field trials.

Man-Machine-Interface Software Design of a Cotton Harvester Yield Monitor Calibration System

Several yield monitors are available for use on cotton harvesters, but none are able to maintain yield measurement accuracy across cultivars and field conditions that vary spatially and/or temporally. Thus, the utility of yield monitors as tools for on-farm research is limited unless steps are taken to calibrate the systems as cultivars and conditions change. This technical note details the man-machine-interface software system design portion of a harvester-based yield monitor calibration system for basket-type cotton strippers. The system was based upon the use of pressure sensors to measure the weight of the basket by monitoring the static pressure in the hydraulic lift cylinder circuit. To ensure accurate weighing, the system automatically lifted the basket to a target lift height, allowed basket time to settle, then weighed the contents of the basket. The software running the system was split into two parts that were run on an embedded low-level micro-controller, and a mobile computer located in the harvester cab. The system was field tested under commercial conditions and found to measure basket load weights within 2.5% of the reference scale. As such, the system was proven to be capable of providing an on-board auto-correction to a yield monitor for use in multi-variety field trials.

Embedded Micro-Controller Software Design of a Cotton Harvester Yield Monitor Calibration System

Several yield monitors are available for use on cotton harvesters, but none are able to maintain yield measurement accuracy across cultivars and field conditions that vary spatially and/or temporally. Thus, the utility of yield monitors as tools for on-farm research is limited unless steps are taken to calibrate the systems as cultivars and conditions change. This technical note details the embedded micro-controller software system design portion of a harvester-based yield monitor calibration system for basket-type cotton strippers. The system was based upon the use of pressure sensors to measure the weight of the basket by monitoring the static pressure in the hydraulic lift cylinder circuit. To ensure accurate weighing, the system automatically lifted the basket to a target lift height, allowed the basket time to settle, and then weighed the contents of the basket. The software running the system was split into two parts, which were run on an embedded low-level micro-controller and a mobile computer located in the harvester cab. The system was field tested under commercial conditions and found to measure basket load weights within 2.5% of the reference scale. As such, the system was proven to be capable of providing an on-board auto-correction to a yield monitor for use in multi-variety field trials.

Human gait structure on stable and unstable surfaces

The aim of the study was to analyze the gait of physically active on stable and unstable surfaces of sports active individuals (canoeists and board sailors). The basic research idea was to identify possible differences in the analysis of the structure of traffic in conditions of stable and unstable surfaces. Materials and Methods The study included n = 18 people of school age. The condition for inclusion in the study was regular sports training. The test was conducted in Sports School in Mragowo, in April 2019, in the field, on a stable (pavement) and unstable (beach volleyball court) surface. Measurements were performed with the InBody 270 body composition analysis device and Wiva® Science sensorimotor device for scientific tracking. The results were processed statistically in Excel and Statistica programs. Results The results were regarded as statistically significant at p<0.05. The study revealed that surface type plays a very important role in gait analysis. Significant differences were observed in the analyzed gait parameters on unstable ground, including cadence (p=0.003), gait rhythm (p=0.02), step length (p=0.007), lift height (p=0.002), left step length (p=0.0006) and right step length (0.024) in unstable conditions, the differences are statistically significantly different from gait in stable surface. Conclusions The analyzed parameters can influence training goals. These factors could be taken into account by sports instructors when designing training programs. Further thorough research into the biomechanics of human gait on unstable surfaces will contribute vital knowledge in various areas of human activity, including sports, rehabilitation and physiotherapy.