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  • 1.
    Abbasi, S.
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.).
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.).
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.).
    Particle emissions from rail vehicles: A review2012Ingår i: Civil-Comp Proceedings, ISSN 1759-3433, Vol. 98Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Emission of airborne particles is a side effect from rail transport. This paper reviews recent research on particle emissions from rail vehicles. Both exhaust and non-exhaust particle emissions are characterized by size, morphology, composition, and size distribution. Current legislation, knowledge of adverse health effects, and available and proposed solutions for emission reductions are also treated. There has been much focus on exhaust emissions, but only a few limited studies have investigated non-exhaust particle emissions, which contain a significant amount of metallic materials. A new method for measuring the airborne wear particle emission rate (AWPER) is proposed as a first step to guide new legislations and to focus further research on non-exhaust airborne emission, i.e., research on the generation mechanisms for particle emissions and their adverse health effects. 

  • 2.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    A comparison between particle characteristics between two railway brake pads2013Rapport (Övrigt vetenskapligt)
  • 3.
    Abbasi, Saeed
    Sharif university of Technology, Iran.
    A feasibilty study to establish freight cars overhaul center (Master thesis), Sharif university of technology2005Självständigt arbete på avancerad nivå (masterexamen), 80 poäng / 120 hpStudentuppsats (Examensarbete)
  • 4.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    A study of nanostructured particles in railway tunnels2013Rapport (Övrigt vetenskapligt)
  • 5.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Characterisation of airborne particles from rail traffic2011Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Since the investigation of wear particles in rail transport started in late-1910s, the high mass concentration of these particles has raised worries among researchers concerned with air quality. However, effective action has yet to be taken because of lack of relevant knowledge. This thesis provides applicable information for the airborne wear particles in rail transport. Some aspects of their characteristics such as diameter size, mass concentration, number concentration, and morphology of particles were investigated in field tests and laboratory tests.The effects on particle characterisations from different operational conditions in the field tests, and applying different braking materials, conducting tests in different applied loads or sliding velocities in the laboratory tests were studied. The main advantage of conducting laboratory tests was to focus on studying particles from one source. The possibility of repetition, using high sensitive instruments and conducting tests at low costs are the other advantages of laboratory studies. Paper A describes how a pin-on-disc machine was used to reproduce similar real operational conditions during mechanical braking in a train. The results were validated by comparing the field tests results with the laboratory studies. The particles morphology and size distribution were also studied.Paper B presents a summary of field tests results. The effects of curve negotiating and applying braking in different real conditions were investigated with an on-board measurement.The element composition of the particles and their potential sources were also investigated outside of the particles morphologies.Paper C presents comprehensive results from laboratory studies on airborne particles from different braking materials. The differences in the particle characteristics in similar test conditions were attributable to different material compositions and dominant wear mechanisms. A new index was introduced in this paper and is suggested to be used as a qualitative factor with regard to the airborne wear particle emission rate.Paper D is a review of the recent studies of exhaust emission and non-exhaust emission from rail vehicles. A summary of results, measurements, adverse health effects, and proposed or applied solutions are reviewed in this paper.

  • 6. Abbasi, Saeed
    Implementing theory of constraint in choosing six sigma project2008Konferensbidrag (Refereegranskat)
  • 7.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Nanostructured particles in/outside compartment of running train, an on board measurement2013Rapport (Övrigt vetenskapligt)
  • 8.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Non-exhaust Nano particle emission in Rail traffic2010Konferensbidrag (Refereegranskat)
  • 9.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Towards elimination of airborne particles from rail traffic2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Since the investigation of wear particles from rail transport started in the late 1910s, the high mass concentrations of these particles have prompted concern among researchers interested in air quality. However, effective action has yet to be taken because relevant knowledge is still missing. This thesis provides knowledge of airborne wear particles originating from rail transport. Some aspects of their characteristic parameters, such as size, mass concentration, number concentration, and morphology, were investigated in the field and in laboratory tests. We also discuss means to mitigate non-exhaust emissions, as well as the advantages and disadvantages of various test set-ups in the seven appended journal papers:Paper A reviews recent studies of exhaust and non-exhaust emissions from rail vehicles. The results, measurements, adverse health effects, and proposed or applied solutions presented in this literature are summarized in this paper.Paper B summarizes the results of field tests we conducted. The effects of curve negotiation and braking under different real conditions were investigated in a field test in which on-board measurements were made. The elemental composition and morphology of the particles emitted and their potential sources were also investigated.Paper C describes how a pin-on-disc machine can be used to reproduce real operating conditions during mechanical train braking in a controlled laboratory setting. The results were validated by comparing the field test results with the results of laboratory studies.Paper D presents comprehensive results of laboratory studies of airborne particles from different braking materials. A new index is introduced in this paper, which can be used as a quantitative metric for assessing airborne wear particle emission rates.Paper E describes the effects of using various friction modifiers and lubricants on the characteristics of airborne particles from wheel–rail contact under lubricated and unlubricated conditions.Paper F reports work to simulate thermoelastic instability in the cast-iron braking material. We simulated the fluctuation of the flash temperature by considering the temperature dependency of the material properties and the transformation of the contact state due to thermomechanical phenomena and wear.Paper G reviews new full- and sub-scale measurements of non-exhaust emissions from ground transport. The advantages and disadvantages of on-board measurements, pin-on-disc tests, dynamometer tests, and test rig studies are discussed in this paper.

  • 10. Abbasi, Saeed
    Utilizing the integrated six sigma and lean methodology2008Konferensbidrag (Övrigt vetenskapligt)
  • 11.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Ekstrand-Hammarström, Barbara
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI),.
    Bergström, Ulrika
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI),.
    Bucht, Anders
    Deptartment of Public Health and Clinical Medicine, Umeå University Hospital, Umeå, 901 89, Sweden.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Jansson, Anders
    Department of Applied Environmental Science, Stockholm University, Stockholm, 106 91, Sweden.
    Biological response in lung cells by brake dust from a novel set-up to generate one sourcewear particles2013Konferensbidrag (Refereegranskat)
  • 12.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Jansson, Anders
    Stockholm University, Applied Environmental Science, Stockholm, Sweden.
    Olander, Lars
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installationsteknik.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    A pin-on-disc study of the rate of airborne wear particle emissions from railway braking materials2012Ingår i: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 284, s. 18-29Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The current study investigates the characteristics of particles generated from the wear of braking materials, and provides an applicable index for measuring and comparing wear particle emissions. A pin-on-disc tribometer equipped with particle measurement instruments was used. The number concentration, size, morphology, and mass concentration of generated particles were investigated and reported for particles 10 nm-32 mu m in diameter. The particles were also collected on filters and investigated using EDS and SEM. The effects of wear mechanisms on particle morphology and changes in particle concentration are discussed. A new index, the airborne wear particle emission rate (AWPER), is suggested that could be used in legislation to control non-exhaust emissions from transport modes, particularly rail transport.

  • 13.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Jansson, Anders
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Particle emissions from rail traffic: a literature review2013Ingår i: Critical reviews in environmental science and technology, ISSN 1064-3389, E-ISSN 1547-6537, Vol. 43, nr 23, s. 2211-2244Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Particle emissions are a drawback of rail transport. This work is a comprehensive presentation of recent research into particle emissions from rail vehicles. Both exhaust and non-exhaust particle emissions are considered when examining particle characteristics such as  PM10, and PM2.5 concentration levels, size, morphology, composition, as well as adverse health effects, current legislation, and available and proposed solutions for reducing such emissions. High concentration levels in enclosed rail traffic environments are reported and some toxic effects of the particles. We find that only a few limited studies have examined the adverse health effects of non-exhaust particle emissions and that no relevant legislation exists. Thus further research in this area is warranted.

  • 14.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Moslemi, Kianoush
    A new approach for optimization of heating system in tank wagons2003Konferensbidrag (Refereegranskat)
  • 15.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olander, Lars
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installationsteknik.
    Larsson, Christina
    Bombardier Transportation Sweden AB, Västerås, Sweden.
    Jansson, Anders
    Stockholm University, Applied Environmental Science, Stockholm, Sweden.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Tribologi.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    A field test study of airborne wear particles from a running regional train2012Ingår i: IMechE, Part F: Journal of Rail and Rapid Transit, ISSN 0954-4097, Vol. 226, nr 1, s. 95-109Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Inhalable airborne particles have inverse health affect. In railways, mechanical brakes, the wheel–rail contact, current collectors, ballast, sleepers, and masonry structures yield particulate matter. Field tests examined a Swedish track using a train instrumented with particle measurement devices, brake pad temperature sensors, and speed and brake sensors. The main objective of this field test was to study the characteristics of particles generated from disc brakes on a running train with an on-board measuring set-up.

    Two airborne particle sampling points were designated, one near a pad–rotor disc brake contact and a second under the frame, not near a mechanical brake or the wheel–rail contact; the numbers and size distributions of the particles detected were registered and evaluated under various conditions (e.g. activating/deactivating electrical brakes or negotiating curves). During braking, three speed/temperature-dependent particle peaks were identified in the fine region, representing particles 280 nm, 350 nm, and 600 nm in diameter. In the coarse region, a peak was discerned for particles 3–6 μm in diameter. Effects of brake pad temperature on particle size distribution were also investigated. Results indicate that the 280 nm peak increased with increasing temperature, and that electrical braking significantly reduced airborne particle numbers. FESEM images captured particles sizing down to 50 nm. The ICP-MS results indicated that Fe, Cu, Zn, Al, Ca, and Mg were the main elements constituting the particles.

     

  • 16.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    A study of friction modifiers on airborne wear particles from wheel-rail contact2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    Wheel-rail contact and its wear process are crucial issues in maintenance and operating of rolling stocks. During wheel-rail contact, materials in mating faces are worn off and some of them transferred to airborne particles. Eventhough the wear process in wheel-rail contact are well-known, few studies have been conducted on the airborne particles from wheel-rail contact.

    The purpose of this study is to investigate the effect of using different friction modifier on the amount of airbotne particles from wheel-rail contact in a laboratory simulation. In this regard, a series laboratory tests were used by using round head pin (R=25mm) and dead weight 40 N in a pin-on-disc machine. This set-up simulates a contact pressure around 750 MPa on the pin head.

    The amount of airborne particles and their characteristics were investigated in dry-contact, and non-dry contacts whereas a lubricant, Binol rail 510 and a friction modifier, tramsilence were used. According to the results, the effects of using Binol rail to reduce the amount of airborne particles were considerable.

  • 17.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Airborne wear particles from train traffic2010Konferensbidrag (Refereegranskat)
  • 18.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.).
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.).
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.).
    Experiences of measuring airborne wear particles from braking materials and the wheel - Rail contact2012Ingår i: 9th International Conference on Contact Mechanics and Wear of Rail/Wheel Systems, CM 2012, Southwest Jiaotong University , 2012, s. 608-609Konferensbidrag (Refereegranskat)
    Abstract [en]

    During braking both of the discs and pads of disc brakes are worn. Since disc brakes are not sealed, some of the generated wear particles can become airborne. The same condition also holds for block brakes utilized in rail vehicles. Furthermore, the wheel-rail contact is also subjected to wear processes during braking as well as during normal running. This contact also contributes to generation of airborne particles. Several studies have found an association between adverse health effects and the concentration of particles in the atmosphere, so it is of interest to improve our knowledge of the airborne wear particles. The present work includes results from full scale testing of rail vehicles. Particle size distribution, morphology and elemental contents are presented and discussed. Due to high back ground concentration levels in field tests, dedicated laboratory test set ups on a reduced scale were designed and utilized for airborne particle studies with zero background level. Promising correlation between field test and the lab set up is identified. Different ways of using this test set up for evaluating how the composition of the airborne particles is classified with respect to their health effects are discussed. Furthermore, different ways of using the proposed method to rank and to quantify airborne particle emission factors are presented.

  • 19.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Experiences of measuring airborne wear particles from braking materials and wheel-rail contact2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    During braking both of the discs and pads of disc brakes are worn. Since disc brakes are not sealed, some of the generated wear particles can become airborne.  Wheel-rail is also subjected to wear process during braking as well as normal running. They also contribute to generate airborne particles. Several studies have found an association between adverse health effects and the concentration of particles in the atmosphere, so it is of interest to improve our knowledge of the airborne wear particles generated by disc brakes.

    The present work includes results from full scale testing of rail vehicles. Particle size distribution, morphology and elemental contents are presented and discussed for different combinations of disc and pad materials. Due to high back ground concentration levels in field tests, dedicated laboratory test set ups on a reduced scale were designed and utilized for airborne particle studies with zero background level.

    Promising correlation between field test and the lab set up is identified. Different ways of using this test set up for evaluating how the composition of the airborne particles is classified with respect to their health effects are discussed. Furthermore, different ways of using the proposed method to rank and to quantify airborne particle emission factors are presented.

  • 20.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Lack of applicable criteria in non-exhaust emission legislation: AWPER index a practical solution2011Konferensbidrag (Refereegranskat)
  • 21.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olander, Lars
    A field investigation of the size and morphology and chemical composition of airborne particles in rail transport2010Konferensbidrag (Refereegranskat)
  • 22.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olander, Lars
    Larsson, christina
    A field investigation of the size, morphology and chemical composition of airborne particles in rail transport2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    The health effects of inhalable airborne particles are well documented. In the European Union the European Council mandates that the level of airborne particles with a diameter smaller than 10 µm (PM10) must not exceed an annual average of 40 µg/m3. Examples of possible sources from rail transport are mechanical brakes, wheel rail contact, current collectors, ballast, sleepers and masonry structures. In this regard, a series of field tests have been conducted on a regular Swedish track using a regional train instrumented with: particle measurement devices, temperature sensors in brake pads and sensors to measure the magnitude of train speed and a GPS.

    Two sampling points for airborne particles were designated in the train under frame. One of the sampling points was near a pad to rotor disc brake contact and a second global sampling point was chosen under the frame, but not near a mechanical brake or the wheel-rail contact. The first one was highly influenced by brake pad wear debris and the other one was influenced by all of the brake pads, wheel and rail wear debris as well as re-suspension. In each sampling points, three tubes were linked to three particle measurement devices. Two sets of Ptrak, Dustrak and Grimm devices were used. The Ptrak 8525 was an optical particle measurement device which could measure particle diameter in the size interval of 20 nm up to 1 micrometer. The Dustrak was used to measure particle mass concentration. The Grimm 1.109 was an aerosol spectrometer which counted number of particles from 0.25 micrometer to 32 micrometer in 31 intervals. These two Grimm devices were equipped with Millipore filters in the devices outlets to capture particles for further studies on morphology and matter of particles.

    The total number and size distribution of the particles for these two sampling points were registered and evaluated in different situations such as activating and deactivating electrical brake or train curve negotiating.

    During braking, three peaks of 250 nm, 350 nm and 600 nm in diameter, with the 350 nm peak dominating were identified in the fine particle region. In the coarse particle region, a peak of around 3-6 µm in diameter was discovered. The brake pad temperature effects on particle size distribution were also investigated and the results showed that the peak around 250 nm increased. Furthermore, the activation of electrical braking significantly reduced the number of airborne particles.

    A SEM was used to capture the images from collected particles on filters. Furthermore, an ICP-Ms method was used to investigate the elemental contents of the particulates on the filter.  In this case the main contribution belonged to Fe, Si, Al, Ca, Cu, Zn. The higher amount of some elements weights such as calcium, silicon, sodium and aluminum in the global sampling point filters revealed that ballast and concrete sleepers were the main sources for these particles although some of them originated from rail, wheel, brake disc and brake pad as well.

  • 23.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Tritscher, Trosten
    TSI.
    Krinke, Thomas
    TSI.
    On-board study of nano- and micrometer-particle characteristics of a running electric train2013Konferensbidrag (Refereegranskat)
  • 24.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Zhu, Yi
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Pin-on-disc study of the effects of railway friction modifiers on airborne wear particles from wheel-rail contact2013Ingår i: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 60, s. 136-139Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Knowledge of wheel–rail interaction is crucial to wheel and rail maintenance. In this interaction, some of theworn-off material is transformed into airborne particles. Although such wear is well understood, few studiestreat the particles generated. We investigated friction modifiers' effects on airborne particles characteristicsgenerated in wheel-rail contacts in laboratory conditions. Pin-on-disc machine testing with a round-head pinloaded by a dead weight load 40 N simulated maximum contact pressure over 550 MPa. Airborne particlecharacteristics were investigated in dry contacts and in ones lubricated with biodegradable rail grease andwater- and oil-based friction modifiers. The number of particles declined with the grease; the number ofultrafine particles increased with the water-based friction modifier, mainly due to water vaporization.

  • 25.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Particle emission from rail vehicles: A literature review2012Ingår i: Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, Sage Publications, 2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    Emission of airborne particles is a side effect from rail transport. This work reviews recent research on particle emissions from rail vehicles. Both exhaust and non-exhaust particle emissions are characterized by size, morphology, composition, and size distribution. Current legislation, knowledge of adverse health effects, and available and proposed solutions for emission reductions are also treated. There has been much focus on exhaust emissions, but only a few limited studies have investigated non-exhaust particle emissions, which contain a significant amount of metallic materials. A new method for measuring the airborne wear particle emission rate (AWPER) is proposed as a first step to guide new legislations and to focus further research on non-exhaust airborne emission, i.e., research on the generation mechanisms for particle emissions and their adverse health effects.

  • 26.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Technical note: Experiences of studying airborne wear particles from road and rail transport2013Ingår i: Aerosol and Air Quality Research, ISSN 1680-8584, Vol. 13, nr 4, s. 1161-1169Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Airborne particles and their adverse effects on air quality have been recognized by humans since ancient times. Current exhaust emission legislations increase the relative contribution of wear particles on the PM levels. Consequently, wearbased particle emissions from rail and road transport have raised concerns as ground transportation is developing quickly. Although scientific research on airborne wear-based particles started in 1909, there is almost no legislation that control the generation of wear-based particles. In addition, there is no accepted and approved standard measurement technique for monitoring and recording particle characteristics. The main objective of this study is to review recent experimental work in this field and to discuss their set-ups, the sampling methods, the results, and their limitations, and to propose measures for reducing these limitations.

  • 27.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. Department of Mechanical engineering, Golpayegan University of Technology.
    Teimourimanesh, Shahab
    Chalmers.
    Vernersson, Tore
    Chalmers.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Lunden, Roger
    Chalmers.
    Temperature and Thermoelastic Instability at Tread Braking Using Cast Iron Friction Material2013Ingår i: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 314, nr 1–2, s. 171-180Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Braking events in railway traffic often induce high frictional heating and thermoelastic instability (TEI) at the interfacing surfaces. In the present paper, two approaches are adopted to analyse the thermomechanical interaction in a pin-on-disc experimental study of railway braking materials. In a first part, the thermal problem is studied to find the heat partitioning between pin and disc motivated by the fact that wear mechanisms can be explained with a better understanding of the prevailing thermal conditions. The numerical model is calibrated using the experimental results. In a second part, the frictionally induced thermoelastic instabilities at the pin-disc contact are studied using a numerical method and comparing them with the phenomena observed in the experiments. The effects of temperature on material properties and on material wear are considered. It is found from the thermal analysis that the pin temperature and the heat flux to the pin increase with increasing disc temperatures up to a transition stage. This agrees with the behaviour found in the experiments. Furthermore, the thermoelastic analysis displays calculated pressure and the temperature distributions at the contact interface that are in agreement with the hot spot behaviour observed in the experiments.

  • 28.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Teimourimanesh, Shahab
    Chalmers.
    Vernersson, Tore
    Chalmers.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Lunden, Roger
    Chalmers.
    Temperature and thermo-elastic instability of tread braking friction materials2012Konferensbidrag (Refereegranskat)
  • 29.
    Abbasi, Saeed
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Wahlström, Jens
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Olander, Lars
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Installationsteknik.
    Larsson, Christina
    Bombardier Transportation Sweden AB, Västerås, Sweden.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Tribologi.
    Sellgren, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    A study of airborne wear particles generated from organic railway brake pads and brake discs2011Ingår i: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 273, nr 1, s. 93-99Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    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 find means of controlling the number and size distribution of airborne particles. In this regard, a series of full-scale field tests and laboratory tests with a pin-on-disc machine have been conducted. The morphology and the matter of particles, along with their size distribution and concentration, have been studied. The validity of results from the pin-on-disc simulation has been verified by the field test results. Results show an ultra-fine peak for particles with a diameter size around 100 nm in diameter, a dominant fine peak for particles with a size of around 350 nm in diameter, and a coarse peak with a size of 3-7 μm in diameter. Materials such as iron, copper, aluminium, chromium, cobalt, antimony, and zinc have been detected in the nano-sized particles.

  • 30. Arab, Ghasem
    et al.
    Ghadamian, Hossein
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.).
    Thermo-economic modeling of an atmospheric SOFC/CHP cycle: an exergy based approach2014Ingår i: Mechanics and Industry, ISSN 2257-7777, Vol. 15, nr 2, s. 113-121Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sustainability is one of the challenging issues in electricity production systems. Recently, solid oxide fuel cell (SOFC) has been suggested for use in combined heat and power (CHP) systems. This application is introduced as a promising environmentally-friendly system according to the thermodynamic and electrochemical models. In this paper, an atmospheric SOFC/CHP cycle was analysed based on integrating exergy concepts, energy and mass balance equations. In this regard, a zero-dimensional energy and mass balance model was developed in engineering equation solver (EES) software. Two dimensionless parameters (the exergetic performance coefficient (EPC) for investigating the whole cycle, and exergetic efficiency for investigating the exergy efficiency of the main component of this cycle) were applied. Results show that efficiencies of the system have been increased substantially. The electrical efficiency, total efficiency and EPC of this cycle were similar to 54%, similar to 79% and similar to 58% respectively. Moreover, the CO2 emission is 19% lower than when compared with a conventional combined power cycle fed by natural gas. In addition, a dynamic economic evaluation was performed to extract the most sensitive parameters affecting the outputs: electricity sales price (ESP), equipment purchase cost and fuel cost. Furthermore, an electricity production cost of similar to 125 $ MW.h(-1) was attributed to our model, resulting in yet further cost reduction for widespread applications of this cycle.

  • 31.
    Cha, Yingying
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Tribologi.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Tribologi.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Tribologi.
    Indoor and outdoor measurement of airborne particulates on a commuter train running partly in tunnels2018Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 232, nr 1, s. 3-13Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Wear processes from mechanical braking, rail/wheel contact, the railway electrification system and re-suspended materials due to the turbulence of passing trains in tunnels and stations have been suggested to be the main contributors to particulate matter levels inside trains. In this study, onboard monitoring was performed on a commuter train stopping at underground and aboveground stations. The concentration and size distribution of particulates were monitored for both indoor and outdoor levels. The results show that the levels of PM10 and PM2.5 inside the train were about one-fifth of the outdoor levels. Significant increases in indoor particulate number concentrations were observed in tunnel environments and there was a slight increase when the doors were open. Differences in the size distributions of micro- and nano-sized particulates could be identified for different tunnels.

  • 32.
    Darvish, Parviz
    et al.
    ESSEC Business School.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Risk Hedging Optimal Capacity in the European Hub-based Natural Gas Market Network: A Model-based ApproachArtikel i tidskrift (Refereegranskat)
  • 33.
    Gustafsson, Mats
    et al.
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Blomqvist, Göran
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Gudmundsson, Anders
    Division of Ergonomics and Aerosol Technology, Lund University, SE 221 00, Lund, Sweden.
    Janhäll, Sara
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Johansson, Christian
    Department of Applied Environmental Science, Stockholm University, SE 106 91, Stockholm, Sweden.
    Norman, Micheal
    Stockholm Environment and Health Administration, SLB-analys, SE 104 20, Stockholm, Sweden.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sjövall, Bill
    Stockholm Environment and Health Administration, SLB-analys, SE 104 20, Stockholm, Sweden.
    Wilhelmsson, H
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Particles in road and railroad tunnel air: properties, sources and abatement possibilities2013Konferensbidrag (Refereegranskat)
  • 34.
    Janhäll, Sara
    et al.
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Mats, Gustafsson
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Blomqvist, Göran
    VTI - Swedish National Road and Transport Research Institute, Linköping, SE 581 95, Sweden.
    Gudmundsson, Anders
    Division of Ergonomics and Aerosol Technology, Lund University, Lund, SE 221 00, Sweden.
    Johansson, Christian
    Department of Applied Environmental Science, Stockholm University, Stockholm, SE 106 91, Sweden.
    Norman, Michael
    Stockholm Environment and Health Administration, SLB-analysis, Stockholm, SE 104 20, Sweden.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Sjövall, Bill
    Stockholm Environment and Health Administration, SLB-analysis, Stockholm, SE 104 20, Sweden.
    Road tunnels - particle properties, wet and dry conditions2013Konferensbidrag (Refereegranskat)
  • 35.
    Lewis, Roger
    et al.
    Department of Mechanical Engineering, University of Sheffield.
    Lewis, S.
    Department of Mechanical Engineering, University of Sheffield.
    Zhu, Yi
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Tribologi. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Tribologi.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    The Modification of a Slip Resistance Meter for Measurement of Railhead Adhesion2013Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 227, nr F2, s. 196-200Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this work was to find a quick, flexible and localised method for determining railhead adhesion. The proposed method is a pendulum rig, which has a rubber pad at the base of a swinging arm. The arm is released and as the rubber pad slides across the contact surface, energy is lost. This loss can be translated into a friction coefficient. Tests have been performed under dry and contaminated conditions, including water, oil and leaf layers both in the laboratory on extracted rail and in the field on live rail. Friction modifiers were also tested. The results of these tests are compared with data obtained using a hand-pushed tribometer. The performed study shows that the pendulum is a viable way to test adhesion levels in the field.

  • 36.
    Olofsson, Ulf
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Zhu, Yi
    KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG. KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement.
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Lewis, Roger
    Lewis, Steve
    Tribology of the wheel rail contact: aspects of wear, particle emission and adhesion2013Ingår i: Vehicle System Dynamics, ISSN 0042-3114, E-ISSN 1744-5159, Vol. 51, nr 7, s. 1091-1120Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The wheel−rail contact is a safety critical interface. Wear, particle emission and adhesion are all wheel−rail contact phenomena and are discussed here. All three phenomena are material and system parameters and are linked together. Different countermeasures to one phenomenon such as adhesion enhancement with a friction modifier can increase the wear in the contacting bodies. The wear of railway wheel and rail is linked to the number of airborne particles generated, but the exact number and size distribution of the aerosols particles are unknown. The main objective of this study is to review recent work in this field and to discuss future trends.

  • 37. Vernersson, Tore
    et al.
    Lunden, Roger
    Abbasi, Saeed
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Olofsson, Ulf
    KTH, Skolan för industriell teknik och management (ITM), Maskinkonstruktion (Inst.), Maskinelement. KTH, Skolan för teknikvetenskap (SCI), Centra, Järnvägsgruppen, JVG.
    Wear of Railway brake block materials at elevated temperatures: pin-on-disc experiments2012Ingår i: Proceedings of Eurobrake 2012, FISITA, 2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    An experimental study on a pin-on-disc rig is presented where the wear of some brake block materials at controlled elevated disc temperatures are reported. It is found for the three studied organic composite materials that the (specific) wear rate increases radically at a temperature of about 500 oC. For temperatures below 500 oC, the wear rate is found to increase with temperature. The cast iron material shows an increase of the wear rate up to 500 oC, after which a transition in the wear mechanism occurs and the wear rate is decreasing with increasing temperature. The studied sinter material shows a weak dependence of the wear rate with temperature.

1 - 37 av 37
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