Experimental and numerical analysis of the roller-bench endurance test on a motorscooter

Author(s):  
F Frendo ◽  
W Rosellini

This paper describes an activity aimed at analysing the loads occurring on a two-wheeler during one of the most widespread tests among two-wheeler companies. In this test, the vehicle with additional ballasts, is positioned on two rollers, having synchronized rotational speed, and is subjected to loads coming from obstacles positioned on the rollers' surface. In order to achieve an in-depth understanding of the loads produced by the test, a vehicle was provided with displacement transducers, accelerometers, and strain gauges. At the same time, two multi-body models of the test were set up, in which the motorscooter had a rigid frame or a flexible frame respectively. The dynamics of the tyre was reproduced by the rigid ring model, where the tyre interacts with the wheel rim by means of linear and rotational springs and dampers. The loads from the obstacles are evaluated on the basis of a series of experimental curves (envelope properties of the tyre) directly obtained with the tyres and obstacle employed for the tests. The comparison between experimental and numerical results regarding suspension strokes, wheel vertical accelerations, and vertical and longitudinal loads showed fairly good agreement; it is also shown how the model having the rigid frame overestimates the peaks in the vertical load. The availability of an accurate model for this kind of test in the early phase of the development process of new vehicles, allows the design of structural components to be optimized.

1995 ◽  
Vol 23 (1) ◽  
pp. 26-51 ◽  
Author(s):  
S. Kagami ◽  
T. Akasaka ◽  
H. Shiobara ◽  
A. Hasegawa

Abstract The contact deformation of a radial tire with a camber angle, has been an important problem closely related to the cornering characteristics of radial tires. The analysis of this problem has been considered to be so difficult mathematically in describing the asymmetric deformation of a radial tire contacting with the roadway, that few papers have been published. In this paper, we present an analytical approach to this problem by using a spring bedded ring model consisting of sidewall spring systems in the radial, the lateral, and the circumferential directions and a spring bed of the tread rubber, together with a ring strip of the composite belt. Analytical solutions for each belt deformation in the contact and the contact-free regions are connected by appropriate boundary conditions at both ends. Galerkin's method is used for solving the additional deflection function defined in the contact region. This function plays an important role in determining the contact pressure distribution. Numerical calculations and experiments are conducted for a radial tire of 175SR14. Good agreement between the predicted and the measured results was obtained for two dimensional contact pressure distribution and the camber thrust characterized by the camber angle.


1996 ◽  
Vol 150 ◽  
pp. 409-413
Author(s):  
Patrick P. Combet ◽  
Philippe L. Lamy

AbstractWe have set up an experimental device to optically study the scattering properties of dust particles. Measurements over the 8 — 174° interval of scattering angles are performed on a continuously flowing dust loaded jet illuminated by a polarized red HeNe laser beam. The scattering is averaged over the population of the dust particles in the jet, which can be determined independently, and give the “volume scattering function” for the two directions of polarization directly. While results for spherical particles are in good agreement with Mie theory, those for arbitrary particles show conspicuous deviations.


1984 ◽  
Vol 106 (1) ◽  
pp. 29-35 ◽  
Author(s):  
P. Cawley

The susceptibility to bias error of two methods for computing transfer (frequency response) functions from spectra produced by FFT-based analyzers using random excitation has been investigated. Results from tests with an FFT analyzer on a single degree-of-freedom system set up on an analogue computer show good agreement with the theoretical predictions. It has been shown that, around resonance, the bias error in the transfer function estimate H2 (Syy/Sxy*) is considerably less than that in the more commonly used estimate, H1 (Sxy/Sxx). The record length, and hence the testing time, required for a given accuracy is reduced by over 50 percent if the H2 calculation procedure is used. The analysis has also shown that if shaker excitation is used on lightly damped structures with low modal mass, it is important to minimize the mass of the force gage and the moving element of the shaker.


Author(s):  
D M Sirkett ◽  
B J Hicks ◽  
C Berry ◽  
G Mullineux ◽  
A J Medland

The folding carton is a widely used packaging solution. Recent European Union packaging legislation has forced carton manufacturers to use lighter-weight grades of carton board. This typically results in a reduction in board stiffness, which can lead to decreased process efficacy or even prevent successful processing. In order to overcome this, end-users lower production rates and fine-tune packaging machine settings for each pack and material. This trial-and-error approach is necessary because the rules relating machine set-up to pack design and material properties are not generally well known. The present study addresses this fundamental issue through the creation of a finite-element computer simulation of carton processing. Mechanical testing was performed to ascertain the key mechanical properties of the carton walls and creases. The carton model was validated against the experimental results and was then subjected to the machine-material interactions that take place during complex packaging operations. The overall approach was validated and the simulation showed good agreement with the physical system. The results of the simulation can be used to determine guidelines relating machine set-up criteria to carton properties. This will improve responsiveness to change and will ultimately allow end-users to process thinner lighter-weight materials more effectively.


Author(s):  
Carlo Cialdai ◽  
Dario Vangi ◽  
Antonio Virga

This paper presents an analysis of the situation in which a two-wheeler (i.e. a motorcycle, where the term motorcycles includes scooters) falls over to the side and then successively slides; this typically occurs in road accidents involving this type of vehicle. Knowing the deceleration rate of the sliding phase allows the kinetic energy dissipated and the speed of the motorcycle just before the fall to the ground to be calculated. These parameters are very important in the analysis and reconstruction of accidents. The work presented in this paper was developed in two experimental test sessions on fully faired motorcycles which are mainly of the scooter type and widely used in urban areas. In the first session, sliding tests were carried out, with the speed in the range 10–50 km/h, on three different types of road surface. Analysis of the evidence allowed the dissipative main phases of motion of the motorcycle (the impact with the ground, the rebounds and the stabilized swiping) to be identified and some factors affecting the phenomenon to be studied. The coefficient of average deceleration was calculated using two typical equations. The second test session consisted of drag tests. In these tests, the motorcycle, which had previously laid on its side, was dragged for a few metres at a constant speed of about 20 km/h, while the drag force was measured. A comparison of the results obtained in these tests with those obtained in the sliding tests yielded very good agreement in the coefficients of deceleration.


2021 ◽  
pp. 64-66
Author(s):  
K. Karthika.

This study has been carried out to evaluate the nancial performance of HDFC bank. HDFC was amongst the rst to receive an 'in principle' approval from the Reserve Bank of India (RBI) to set up a bank in the private sector. HDFC Bank is the second largest Private sector Bank in India and one of the top 5 banks in the country. The bank has a network of 5000+branches and 16000+ATMs in 2902 cities/towns. HDFC Bank provides a number of products and services including wholesale banking and retail banking, treasury, auto loans, two wheeler loans, personal loans against property, consumer durable loans, life style loan, credit cards and the various digital products. The nancial performance of above mentioned bank has been evaluated for the past ve years i.e. 2017, 2018, 2019, 2020, 2021. The data analyzed by ratio analysis such as current ratio, liquid ratio, xed assets ratio, debt-equity ratio and net prot ratio and give interpretation to each ratio. To conclude this nancial soundness of the bank is satisfactory during the study period.


2012 ◽  
Vol 525-526 ◽  
pp. 385-388
Author(s):  
Tian Jiao Qu ◽  
Xi Tao Zheng ◽  
Di Zhang

After the low-velocity impact test of composite laminates of T800/BA9916, CAI test and compression test of laminates with a hole have been carried out. Two types of models were set up by the finite element software ABAQUS respectively. The FEA results were good agreement with the testing results. The investigation of models with a hole indicates that the appearance time of ultimate compressive load is earlier than that of fiber breakage expanding to boundary. Moreover, the diameter and the depth of blind hole significantly influence the ultimate compressive load.


2014 ◽  
Vol 591 ◽  
pp. 193-196 ◽  
Author(s):  
B. Vijaya Ramnath ◽  
K. Venkataraman ◽  
Selvaraj Venkatram ◽  
Sohil Thomas ◽  
Muthukumarasamy Maheshwaran ◽  
...  

- Powered Two Wheelers (PTW) are very sensitive to environmental conditions and advancement in two-wheeler safety has not kept pace with the advancement in two-wheelers. The objective of our research is to bring about an improved design for powered two wheelers, analyzing the changes through simulation and thereby improving the safety considerations. According to the databases referred regarding accidents in depth study, it is observed that two-wheelers top the chart in number of accidents by a big margin and these accidents causes more fatal injuries. To save the rider, this paper proposes to constraint the rider along with pillion to the vehicle using “Leg holding device“ and seat belt. Side airbags are employed to absorb the impact of accident. The present safety system saves the rider in frontal collisions, while this research also focuses on side collisions. ISO 13232 standard accident scenarios were followed. For simulation of scenarios multi body dynamics software called RecurDyn is used. The improvement in employing safety measures is compared with its absence and results are plotted.


2020 ◽  
Vol 27 ◽  
pp. 121
Author(s):  
Filothei K. Pappa ◽  
Christos Tsabaris ◽  
Dionisis Patiris ◽  
Georgios Eleftheriou ◽  
Effrossini G. Androulakaki ◽  
...  

Radionuclides are characterized by their nuclear and chemical behavior. Additionally, the geochemical characteristics of radionuclides result in their accumulation in the sediments via sorption processes. In this work the radionuclide activity concentrations obtained by gamma-ray spectrometry (HPGe detector) were converted to metal concentrations as described in [1]. The results were compared with the measured metal concentrations obtained by atomic spectrometry (X-ray fluorescence system-XRF). The samples originate from the coastal environment of two Greek areas, characterized by elevated values of natural radionuclides (e.g. 226Ra) and metals. The preliminary study revealed a good agreement among the concentrations of potassium calculated via activity concentrations of 40K and those of XRF measurement, while a great divergence was observed for the thorium case. These differences can be attributed to the low statistics, as well as to the calibration set-up of Th XRF measurement.


2002 ◽  
Vol 57 (6-7) ◽  
pp. 333-336
Author(s):  
Evgenii A. Romanenko ◽  
Alexander M. Nesterenko

IThe 35Cl nuclear quadrupole resonances (77 K) and ab initio calculations of trichloromethyldichlorophosphine () show that it exists in the chess conformation form. The barrier to internal rotation about the P-C bond in I at the RHF/6-31++ G(d,p) level equals to 38.1 kJ mol-1. In chloromethyldichlorophosphine (II) the extension of the basis set up to the RHF/6-311++G(df, pd) level does not improve the description of the most preferable gauche-conformation; only if electron correlation (at the MP2 level) is taken into account the results are in a good agreement with experimental data.


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