Experimental Research on Sugarcane Under-the-Ground Basecutting

Basecutting, an important process in mechanical sugarcane harvesting, has important influence on the development of sugarcane mechanical harvesting. Previous studies mainly focus on kinematic and dynamic models in theory and indoor basecutting tests. However, few studies have explored the cutting mode of basecutter and power consumption with under-the-ground basecutting mode. The objective of this study was to compare two different basecutting modes (above-the-ground basecutting and under-the-ground basecutting), investigate the cutting power consumption and the cutting quality when sugarcane was cut in the optimal cutting mode. Through the means of simulation analysis and contrast experiment comparison, it concluded that the under-the-ground basecutting mode was better than above-the-ground basecutting mode to improve the cutting quality but it has increased the cutting power consumption of basecutters. In the under-the-ground basecutting mode, the orthogonal experiment was carried out using the existing sugarcane harvester, in order to minimize the power consumption while keeping the stubble broken rate to an acceptable level. With the power consumption and stubble broken rate being set as the indexes, the effects of basecutting depth, disc rotational speed, and the harvester forward speed on basecutting performance were investigated. Through the analysis of variance and range analysis, the influence of each factor on the evaluation index was obtained, and the best parameter combination with minimum stubble broken rate and power consumption were determined: the basecutting depth was 40 mm, the disc rotation speed was 600 rpm, and the harvester forward speed was 0.6 m/s. This study provided necessary information to guide engineers to design high-performance basecutter with under-the-ground basecutting mode. Keywords: Basecutter, Cutting mode, Power consumption, Stubble broken rate, Under-the-ground basecutting.

Experimental investigation of the squeal characteristics in railway disc brakes

In this study, a bespoke small-scale brake dynamometer was developed to simulate the braking conditions of a railway disc brake system. Braking squeal experiments were performed with this brake dynamometer at different braking pressures and disc rotation speeds, and the influence of these braking parameters on the generation and characterization of the squeal noise was evaluated and discussed. The obtained results show that both the braking pressure and the disc rotation speed have a significant influence on the generation and evolution of the squeal noise. Higher rotation speeds are found to result in higher sound pressures and more complicated squeal noise spectra, except at a particular braking pressure, for which the highest sound pressure level is found at various disc rotation speeds. This phenomenon indicates that a combination of specific braking parameters may lead to a strong instability of the brake system and consequently to squeal noise. Additionally, a possible correlation of the squeal noise characteristics with the pressure distribution at the braking interface was found and discussed.

RESEARCH OF EFFECTIVENESS OF DISK SHAPED ELEMENTS FOR OIL REMOVAL / DISKINIŲ NAFTOS SURINKIMO ELEMENTŲ EFEKTYVUMO TYRIMAS

Influence of grooved disc rotation speed and inclination angle of fluid from surface on amount of removed liquid, was studied in this article. Stand with possibility to change disc, rotation speed of disc and angle was designed and assembled. U and V shaped groove discs were used. Edible and industrial oil SAE 80W90 were removed from water surface and collected into the flash. Optimal disc rotation speed, which is 15 rpm and disc inclination angle 00 were determined after analysis of results. Straipsnyje išnagrinėta skirtingais griovėtais diskais nuo vandens paviršiaus surenkamo skysčio ir jame esančio vandens kiekio priklausomybė nuo griovėto disko sukimosi greičio ir polinkio kampo. Buvo suprojektuotas stendas su galimybėmis pakeisti diską, disko sukimosi greičius bei polinkio kampą. Naudotų diskų griovelių geometrija V ir U formos. Nuo vandens paviršiaus disku buvo renkamas maistinis aliejus ir tepalai 80W90 į sugraduotą kolbą. Atlikus gautų rezultatų analizę, nustatytas optimalus disko sukimosi greitis, kuris lygus 15 aps/min, o polinkio kampas lygus 0°.

Urea Hardness Optimization in a Fluidized Bed Coating Equipment Using Taguchi Design Method

This paper describes the use of Taguchi Method in optimizing coating hardness in a tangential fluidized bed coater using modified biopolymer. During the coating process, granular ureas collide among themselves and the wall surface at high velocity. This led to excessive attrition and likely to break the granular ureas into smaller sizes. Hence, hardness is the critical properties during operations such as packaging and stacking. A series of coating experiments were carried out by using the L9 orthogonal array with 3 levels to determine the effect of inlet air temperature (40, 60 and 80OC), disc rotation speed (40, 60 and 80 rpm) and spraying rate (0.5, 1.0 and 2.0 rpm) on hardness of coated granular urea. The optimized operating parameters in this work were 60OC for inlet air temperature, 60 rpm for disc rotation speed and 2 rpm for spraying rate. The results show that the spraying rate was the most significant factor affecting the hardness of the coated granular urea since the contribution was 69.2 %. No confirmations run for this work were necessary since the optimized operating parameters that were discovered was one of the experiments operating parameters.

Optimization of Coating Thickness in a Tangential Fluidized Bed

The focal intention of this research was to investigate the factors influencing the coating thickness of urea granule by using modified biopolymer which performed in a tangential fluidized bed. The effects of inlet air temperature, disc rotation speed and spraying rate on coating thickness of urea granule were investigated. In this study, the results showed that the significant process parameters which effect the coating thickness was spraying rate (58.585%), followed by disc rotation speed (21.579%) and inlet air temperature (18.883%). The optimized process parameters in this work were 400C for inlet air temperature, 40 rpm for disc rotation speed and 2 rpm for spraying rate. The confirmation run for this work had verified the conclusion from the variance analysis.

Based on ANSYS Large Diameter Metallic High-Speed Rotating Disk Modal Analysis

The modal analysis for rotating disk with pre-stressed in different high speeds were made respectively based on the finite element software of ANSYS. The each order natural frequencies and inherent vibration were revealed. The result shows that disc rotation speed increases, the each order natural frequencies will also increase, and inherent vibration corresponding changes. By introducing the disc frequency deviation factor, the effect of stress stiffing effect for the disc natural frequencies and inherent vibration were analyzed and found that relationship of a quadratic curve between disc frequency deviations and speed.

Cooling Design for the Next Generation Optical Disc Drive

Recently, the data transfer rate and the memory capacity of optical disc drives have been increasing dramatically. To obtain the high data transfer rate and greater memory capacity, the disc rotation speed and the laser power also need to be increased and these cause an increase in the temperature of the laser diode. Therefore, to develop the next generation optical disc drives, an enhanced cooling system is indispensable for the optical pick-up unit that contains the laser diode. As the temperature of the pick-up unit is influenced by the inside air flow induced by the disc rotation, it is quite necessary to grasp the velocity and temperature distribution inside the drive, and also the influence of the disc rotation speed on the temperature of the pick-up unit. Hence we applied PIV measurements and CFD simulations to visualize the flow field and the internal temperature. Then, during the actual disc recording process we measured the temperature of the pick-up unit and the internal air of the drive. As a result, we made clear the dependence of the disc rotation speed on the pick-up unit temperature. In addition, as an example for next generation optical disc drives, we evaluated the cooling system applying a small axial fan inside the drive and confirmed the validity of this fan system.

A Try for Improvement of Performance in Dry Barrel Finishing by Centrifugal Disc Type

The speed-up of the disc rotation in dry centrifugal barrel finishing is done and its influence on finishing characteristics is experimentally examined. The workpiece is a sliced cold rolled bar of plain carbon steel (S45C in JIS, HB221). It is 32mm in diameter and finished to10mm in thickness by belt grinding. The equilateral triangular prism nylon media (1010mm, A#320) is used at 20vol% in media charging ratio. The disc rotation speed is increased up to 500min-1. By speeding up the disc rotation, the finishing speed improves, but the total efficiency decreases.

The dissolution of copper metal by acidified iron(III) in acetonitrile-water solutions

The kinetics and electrochemistry of the dissolution of a rotating copper disc in various acidified acetonitrile-water mixtures containing iron(III) as the oxidant are described. The reaction kinetics were investigated by a chronopotentiometric method in which the time taken for a copper film of known thickness to dissolve was determined. The reaction was shown to be diffusion-controlled over the temperature range (270-304 K) and composition range (1.0-14.5 mol dm-3 acetonitrile) investigated, good agreement being obtained between rate constants calculated from kinetic measurements and those calculated from electrochemical (cathodic polarization) measurements. From these and kinematic viscosity data, diffusion coefficients for iron(III) in acetonitrile-water mixtures were calculated. It was found that, associated with a discontinuous change in the kinematic viscosity at 290 K, there was a corresponding change in the diffusion coefficient. The activation energy for the high-temperature diffusion process was lower than that for the low-temperature process. It was also found that the diffusion coefficient decreased with increasing acetonitrile concentration. Corrosion potential measurements as a function of disc rotation speed and iron(III) concentration are reported. From these measurements, it was inferred that the anodic reaction is under mixed control.