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Airborne wear particles originating from disc brakes are among the main contributors to non-exhaust emissions. The macroscopic wear behaviour of disc brakes can be explained by the growth and destruction of mesoscopic contact plateaus. The pad wear and temperature has earlier been simulated using a cellular automaton mesoscopic approach. The present paper seeks to refine the simulation approach to
Airborne particle emissions from automotive disc brakes, one of the main sources of urban particulate matter, adversely affect health. Field measurement of brake particles is complicated, as various particle sources (such as tailpipe emissions, resuspended road dust and tyre wear) can interfere. Brake particles are usually measured on dyno benches or in model-scale tests in controlled environments
Particle emissions originating from the sliding disc brake contact in disc brakes are a main contributor to PM10 in Europe. The macroscopic friction and wear behaviour can be explained, at the mesoscopic scale level, by the growth and destruction of contact plateaus. This paper further develops a cellular automaton that describes the mesoscopic contact situation by implementing friction, wear, and
Airborne wear particles originating from disc brakes are one important contributor to the concentration of airborne particles in urban environments. It is therefore of interest to improve the knowledge of these particles. The purpose of this article is to investigate the concentration and size distribution of the airborne wear particles generated from the contact between a low-metallic pad materia
Based on the comparative analysis of the experimental values determined for the tribological parameters for the three novel nano-porous composition base and two conventional brake lining materials while friction with the grey cast iron disc, it was shown the considerable high tribological efficiency of the novel nano-porous composition base lining materials in comparison with the conventional (fro
Brake pads on wheel-mounted disc brakes are often used in rail transport due to their good thermal properties and robustness. During braking, both the disc and the pads are worn. This wear process generates particles that may become airborne and thus affect human health. The long term purpose of 'Airborne particles in Rail transport' project is to gain knowledge on the wear mechanisms in order to
Wear particles originating from disc brakes contribute to particulate concentration in the urban atmosphere. In this work novel nanoporous composite-based and conventional brake materials were tested against cast-iron discs in a modified pin-on-disc machine. During testing airborne wear particles were measured online and collected on filters, which were analysed using SEM and EDX. The morphology o
Since brake wear is an important contributor to the concentration of airborne particles in urban atmospheres, it is important to increase our understanding of the origin of these particles. The contact situation between the pad and disc is complicated. Metal fibres in the pad (or other hard materials) form stable contact plateaus, which carry the main part of the load. A flow of wear particles in
Much attention is given to the consequences of airborne particles on human health and well-being. Wear is one source of airborne particles and contributions in the urban environments from wheel-to-rail contacts and disc brakes cannot be neglected. Traditionally, mechanical wear has been associated with the generation of particles of diameters of some microns. However, the research described has fo
During braking, both the rotor and pads experience wear, generating particles that may become airborne. In field tests, it is difficult to distinguish these particles from others in the surrounding environment, so it is preferable to use laboratory test stands to study the amount of airborne wear particles generated. The purpose of this work is to investigate the possibility of separate, capture,
Most modern passenger cars have disc brakes on the front wheels. Unlike drum brakes, disc brakes are not sealed off from the ambient air. During braking, both the rotor and the pads wear, and this wear process generates particles that may become airborne. In field tests it is difficult to distinguish these particles from others in the environment. It is thus preferable to conduct tests using labor
A novel test method was used to study the concentration and size distribution of airborne wear particles from disc brake materials. A pin-on-disc tribometer equipped with particle counting instruments was used as test equipment. Material from four different non-asbestos organic (NAO) pads and four different low metallic (LM) pads were tested against material from grey cast iron rotors. The results
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During braking, both the rotor and the pads are worn in disc brakes. This wear process generates particles which may become airborne. In passenger car field tests it is difficult to distinguish these particles from others in the surrounding environment. It may therefore be preferable to use laboratory test stands and/or simulation models to study the amount of airborne wear particles generated. Th
During braking, there is wear on both the rotor and the pads. This process generates particles that may become airborne. In fi eld tests, it is diffi cult to distinguish these particles from others in the surrounding environment. Therefore, a laboratory test stand has been designed which allows control of the cleanliness of the surrounding air. The test stand consists of a front right brake assemb
Prospects to use III-V technology to increase the performance of key millimeter wave circuits are discussed. We use 60 GHz wavelet generators to form coherent pulses with controllable pulse lengths down to 25 ps under low-power operation. The transmitters are used to demonstrate transmission at high data rates and very low bit-error-rates with simple modulation schemes (OOK) in direct links over s
This article explores four preselected permanent magnet synchronous machine (PMSM) topologies suitable for direct mounting on low pressure spool in a turbo fan engine. The challenge of contributing to More Electric Engine (MEE) development is that the electrical machine needs to operate over wide speed range, take advantage of available space that forces to use a high number of poles and last but
Large intelligent surface (LIS) is a new technology yet to be developed. However, this technology is likely to be implemented using cheap components so as to facilitate its deployment. Therefore, we can expect a performance degradation due to hardware impairments. In this paper, we present a model for these hardware impairments in a receiving LIS and we analyze their effect on the achievable rate
In this paper, we generalize the one-bit quantized low resolution RELAX algorithm to allow for exponentially decaying modes. The resulting greedy algorithm exploits a time-varying threshold to allow for the estimation of the parameters detailing the modes. The improvement offered by the proposed algorithm as compared to its predecessor, and the corresponding Cramér-Rao Lower Bound, is illustrated
The activation of the kallikrein-kinin system is thought to be one of the pathophysiologic mechanisms in acute pancreatitis. A radioimmunoassay for human urinary tissue kallikrein was developed and used to measure tissue kallikrein peritoneal exudate and plasma from 48 patients with severe acute pancreatitis. All patients were treated with intraperitoneal lavage. One group (n = 22) received high d
