The Experts below are selected from a list of 69321 Experts worldwide ranked by ideXlab platform

Bing Chen - One of the best experts on this subject based on the ideXlab platform.

  • seasonal climatic effects and feedbacks of anthropogenic heat release due to Global Energy Consumption with cam5
    Climate Dynamics, 2019
    Co-Authors: Chenglai Wu, Xue Wu, Jian Wu, H. Yang, Bing Chen, Lin Chen, Yiquan Jiang
    Abstract:

    Anthropogenic heat release (AHR) is the heat generated in Global Energy Consumption, which has not been considered in Global climate models generally. The Global high-resolution AHR from 1992 to 2013, which is estimated by using the Defense Meteorological Satellite Program (DMSP)/Operational Linescan System (OLS) satellite data, is implemented into the Community Atmosphere Model version 5 (CAM5). The seasonal climatic effects and possible feedbacks of AHR are examined in this study. The modeling results show that AHR increases the Global annual mean surface temperature and land surface temperature by 0.02 ± 0.01 K (1σ uncertainty) and 0.05 ± 0.02 K (1σ uncertainty), respectively. The Global climatic effect of AHR varies with season: with a stronger climatic effect in the boreal winter leading to Global mean land surface temperature increases by 0.10 ± 0.01 K (1σ uncertainty). In the selected regions (40°N–60°N, 0°E–45°E) of Central and Western Europe the average surface temperature increases by 0.46 K in the boreal summer, and in the selected regions (45°N–75°N, 30°E–140°E) of northern Eurasia the average surface temperature increases by 0.83 K in the boreal winter. AHR changes the height and thermodynamic structure of the Global planetary boundary layer, as well as the stability of the lower troposphere, which affects the Global atmospheric circulation and low cloud fraction. In addition, at the surface both the shortwave radiation flux in the boreal summer and the down-welling longwave flux in the boreal winter change significantly, as a result of the change in low clouds caused by the effect of AHR. This study suggests a possible new mechanism of AHR effect on Global climate through changing the Global low-cloud fraction, which is crucial for Global Energy balance, by modifying the thermodynamic structure and stability of the lower troposphere. Thus this study improves our understanding of the Global climate change caused by human activities.

  • exploring the possible effect of anthropogenic heat release due to Global Energy Consumption upon Global climate a climate model study
    International Journal of Climatology, 2016
    Co-Authors: Bing Chen, Li Dong, Linling Chen, T Nakajima, A Habib
    Abstract:

    The high-resolution Global distribution of anthropogenic heat release (AHR), which is generated by human Energy Consumption, is estimated by means of applying satellite remote sensing. Additionally, it was considered into a Global climate model and the possible climatic effect of AHR is examined in this study. AHR is geographically concentrated and fundamentally correlates with economic activity in Global scale. The current mean AHR flux on the Global scale is approximately 0.03 W m−2; however, the flux reaches a level high enough to influence the regional climate in concentrated urban areas. Global climate model results indicate that AHR may disrupt the normal atmospheric circulation and could have an obvious effect on the surface temperature at middle and high latitudes in summer and winter over the Northern Hemisphere. The climatic effect of AHR differs in various seasons: the Global mean surface temperature could increase by approximately 0.02 K in boreal summer and by 0.10 K in boreal winter. With the continued development of the Global economy and urbanization, the climatic effect of AHR will become increasingly pronounced. The climatic effect of AHR should not be merely confined to the regional climate, AHR is a tiny but essential factor in Global climate and long-term climate change that should not be ignored.

A Erdemir - One of the best experts on this subject based on the ideXlab platform.

  • Global Energy Consumption due to friction and wear in the mining industry
    Tribology International, 2017
    Co-Authors: Kenneth Holmberg, Paivi Kivikytoreponen, Pirita Harkisaari, Kati Valtonen, A Erdemir
    Abstract:

    Abstract Calculations on the Global Energy Consumption due to friction and wear in the mineral mining industry are presented. For the first time, the impact of wear is also included in more detailed calculations in order to show its enormous tribological and economic impacts on this industry. A large variety of mining equipment used for the extraction, haulage and beneficiation of underground mining, surface mining and mineral processing were analysed. Coefficients of friction and wear rates of moving mechanical assemblies were estimated based on available information in literature in four general cases: (1) a Global average mine in use today, (2) a mine with today's best commercial technology, (3) a mine with today's most advanced technology based upon the adaptation of the latest R&D achievements, and (4) a mine with best futuristic technology forecasted in the next 10 years. The following conclusions were reached: • Total Energy Consumption of Global mining activities, including both mineral and rock mining, is estimated to be 6.2% of the total Global Energy Consumption. About 40% of the consumed Energy in mineral mining (equalling to 4.6 EJ annually on Global scale) is used for overcoming friction. In addition, 2 EJ is used to remanufacture and replace worn out parts and reserve and stock up spare parts and equipment needed due to wear failures. The largest Energy consuming mining actions are grinding (32%), haulage (24%), ventilation (9%) and digging (8%). • Friction and wear is annually resulting in 970 million tonnes of CO 2 emissions worldwide in mineral mining (accounting for 2.7% of world CO 2 emissions). • The total estimated economic losses resulting from friction and wear in mineral mining are in total 210,000 million Euros annually distributed as 40% for overcoming friction, 27% for production of replacement parts and spare equipment, 26% for maintenance work, and 7% for lost production. • By taking advantage of new technology for friction reduction and wear protection in mineral mining equipment, friction and wear losses could potentially be reduced by 15% in the short term (10 years) and by 30% in the long term (20 years). In the short term this would annually equal worldwide savings of 31,100 million euros, 280 TWh Energy Consumption and a CO 2 emission reduction of 145 million tonnes. In the long term, the annual benefit would be 62,200 million euros, 550 TWh less Energy Consumption, and a CO 2 emission reduction of 290 million tonnes. Potential new remedies to reduce friction and wear in mining include the development and uses of new materials, especially materials with improved strength and hardness properties, more effective surface treatments, high-performance surface coatings, new lubricants and lubricant additives, and new designs of moving parts and surfaces of e.g. liners, blades, plates, shields, shovels, jaws, chambers, tires, seals, bearings, gearboxes, engines, conveyor belts, pumps, fans, hoppers and feeders.

  • influence of tribology on Global Energy Consumption costs and emissions
    Friction, 2017
    Co-Authors: Kenneth Holmberg, A Erdemir
    Abstract:

    Calculations of the impact of friction and wear on Energy Consumption, economic expenditure, and CO2 emissions are presented on a Global scale. This impact study covers the four main Energy consuming sectors: transportation, manufacturing, power generation, and residential. Previously published four case studies on passenger cars, trucks and buses, paper machines and the mining industry were included in our detailed calculations as reference data in our current analyses. The following can be concluded: Fifty years ago, wear and wear-related failures were a major concern for UK industry and their mitigation was considered to be the major contributor to potential economic savings by as much as 95% in ten years by the development and deployment of new tribological solutions. The corresponding estimated savings are today still of the same orders but the calculated contribution to cost reduction is about 74% by friction reduction and to 26% from better wear protection. Overall, wear appears to be more critical than friction as it may result in catastrophic failures and operational breakdowns that can adversely impact productivity and hence cost.

  • Global Energy Consumption due to friction in trucks and buses
    Tribology International, 2014
    Co-Authors: Kenneth Holmberg, Peter Andersson, Nilsolof Nylund, Kari Makela, A Erdemir
    Abstract:

    Abstract In this paper, we report the Global fuel Energy Consumption in heavy-duty road vehicles due to friction in engines, transmissions, tires, auxiliary equipment, and brakes. Four categories of vehicle, representing an average of the Global fleet of heavy vehicles, were studied: single-unit trucks, truck and trailer combinations, city buses, and coaches. Friction losses in tribocontacts were estimated by drawing upon the literature on prevailing contact mechanics and lubrication mechanisms. Coefficients of friction in the tribocontacts were estimated based on available information in the literature for four cases: (1) the average vehicle in use today, (2) a vehicle with today׳s best commercial tribological technology, (3) a vehicle with today׳s most advanced technology based upon recent research and development, and (4) a vehicle with the best futuristic technology forecasted in the next 12 years. The following conclusions were reached: • In heavy duty vehicles, 33% of the fuel Energy is used to overcome friction in the engine, transmission, tires, auxiliary equipment, and brakes. The parasitic frictional losses, with braking friction excluded, are 26% of the fuel Energy. In total, 34% of the fuel Energy is used to move the vehicle. • Worldwide, 180,000 million liters of fuel was used in 2012 to overcome friction in heavy duty vehicles. This equals 6.5 million TJ/a; hence, reduction in frictional losses can provide significant benefits in fuel economy. A reduction in friction results in a 2.5 times improvement in fuel economy, as exhaust and cooling losses are reduced as well. • Globally a single-unit truck uses on average 1500 l of diesel fuel per year to overcome friction losses; a truck and trailer combination, 12,500 l; a city bus, 12,700 l; and a coach, 7100 l. • By taking advantage of new technology for friction reduction in heavy duty vehicles, friction losses could be reduced by 14% in the short term (4 to 8 years) and by 37% in the long term (8 to 12 years). In the short term, this would annually equal worldwide savings of 105,000 million euros, 75,000 million liters of diesel fuel, and a CO2 emission reduction of 200 million tones. In the long term, the annual benefit would be 280,000 million euros, 200,000 million liters of fuel, and a CO2 emission reduction of 530 million tonnes. • Hybridization and electrification are expected to penetrate only certain niches of the heavy-duty vehicle sector. In the case of city buses and delivery trucks, hybridization can cut fuel Consumption by 25% to 30%, but there is little to gain in the case of coaches and long-haul trucks. Downsizing the internal combustion engine and using recuperative braking Energy can also reduce friction losses. • Electrification is best suited for city buses and delivery trucks. The Energy used to overcome friction in electric vehicles is estimated to be less than half of that of conventional diesel vehicles. Potential new remedies to reduce friction in heavy duty vehicles include the use of advanced low-friction coatings and surface texturing technology on sliding, rolling, and reciprocating engine and transmission components, new low-viscosity and low-shear lubricants and additives, and new tire designs that reduce rolling friction.

  • Global Energy Consumption due to friction in passenger cars
    Tribology International, 2012
    Co-Authors: Kenneth Holmberg, Peter Andersson, A Erdemir
    Abstract:

    Abstract This study presents calculations on the Global fuel Energy Consumption used to overcome friction in passenger cars in terms of friction in the engine, transmission, tires, and brakes. Friction in tribocontacts was estimated according to prevailing contact mechanisms such as elastohydrodynamic, hydrodynamic, mixed, and boundary lubrication. Coefficients of friction in the tribocontacts were estimated based on available information in the literature on the average passenger car in use today, a car with today’s advanced commercial tribological technology, a car with today’s best advanced technology based upon recent research and development, and a car with the best technology forecasted in the next 10 years. The following conclusions were reached: • In passenger cars, one-third of the fuel Energy is used to overcome friction in the engine, transmission, tires, and brakes. The direct frictional losses, with braking friction excluded, are 28% of the fuel Energy. In total, 21.5% of the fuel Energy is used to move the car. • Worldwide, 208,000 million liters of fuel (gasoline and diesel) was used in 2009 to overcome friction in passenger cars. This equals 360 million tonne oil equivalent per year (Mtoe/a) or 7.3 million TJ/a. Reductions in frictional losses will lead to a threefold improvement in fuel economy as it will reduce both the exhaust and cooling losses also at the same ratio. • Globally, one passenger car uses on average of 340 l of fuel per year to overcome friction, which would cost 510 euros according to the average European gas price in 2011 and corresponds to an average driving distance of 13,000 km/a. • By taking advantage of new technology for friction reduction in passenger cars, friction losses could be reduced by 18% in the short term (5–10 years) and by 61% in the long term (15–25 years). This would equal worldwide economic savings of 174,000 million euros and 576,000 million euros, respectively; fuel savings of 117,000 million and 385,000 million liters, respectively; and CO 2 emission reduction of 290 million and 960 million tonnes, respectively. • The friction-related Energy losses in an electric car are estimated to be only about half those of an internal combustion passenger car. Potential actions to reduce friction in passenger cars include the use of advanced coatings and surface texturing technology on engine and transmission components, new low-viscosity and low-shear lubricants and additives, and tire designs that reduce rolling friction.

Kenneth Holmberg - One of the best experts on this subject based on the ideXlab platform.

  • Global Energy Consumption due to friction and wear in the mining industry
    Tribology International, 2017
    Co-Authors: Kenneth Holmberg, Paivi Kivikytoreponen, Pirita Harkisaari, Kati Valtonen, A Erdemir
    Abstract:

    Abstract Calculations on the Global Energy Consumption due to friction and wear in the mineral mining industry are presented. For the first time, the impact of wear is also included in more detailed calculations in order to show its enormous tribological and economic impacts on this industry. A large variety of mining equipment used for the extraction, haulage and beneficiation of underground mining, surface mining and mineral processing were analysed. Coefficients of friction and wear rates of moving mechanical assemblies were estimated based on available information in literature in four general cases: (1) a Global average mine in use today, (2) a mine with today's best commercial technology, (3) a mine with today's most advanced technology based upon the adaptation of the latest R&D achievements, and (4) a mine with best futuristic technology forecasted in the next 10 years. The following conclusions were reached: • Total Energy Consumption of Global mining activities, including both mineral and rock mining, is estimated to be 6.2% of the total Global Energy Consumption. About 40% of the consumed Energy in mineral mining (equalling to 4.6 EJ annually on Global scale) is used for overcoming friction. In addition, 2 EJ is used to remanufacture and replace worn out parts and reserve and stock up spare parts and equipment needed due to wear failures. The largest Energy consuming mining actions are grinding (32%), haulage (24%), ventilation (9%) and digging (8%). • Friction and wear is annually resulting in 970 million tonnes of CO 2 emissions worldwide in mineral mining (accounting for 2.7% of world CO 2 emissions). • The total estimated economic losses resulting from friction and wear in mineral mining are in total 210,000 million Euros annually distributed as 40% for overcoming friction, 27% for production of replacement parts and spare equipment, 26% for maintenance work, and 7% for lost production. • By taking advantage of new technology for friction reduction and wear protection in mineral mining equipment, friction and wear losses could potentially be reduced by 15% in the short term (10 years) and by 30% in the long term (20 years). In the short term this would annually equal worldwide savings of 31,100 million euros, 280 TWh Energy Consumption and a CO 2 emission reduction of 145 million tonnes. In the long term, the annual benefit would be 62,200 million euros, 550 TWh less Energy Consumption, and a CO 2 emission reduction of 290 million tonnes. Potential new remedies to reduce friction and wear in mining include the development and uses of new materials, especially materials with improved strength and hardness properties, more effective surface treatments, high-performance surface coatings, new lubricants and lubricant additives, and new designs of moving parts and surfaces of e.g. liners, blades, plates, shields, shovels, jaws, chambers, tires, seals, bearings, gearboxes, engines, conveyor belts, pumps, fans, hoppers and feeders.

  • influence of tribology on Global Energy Consumption costs and emissions
    Friction, 2017
    Co-Authors: Kenneth Holmberg, A Erdemir
    Abstract:

    Calculations of the impact of friction and wear on Energy Consumption, economic expenditure, and CO2 emissions are presented on a Global scale. This impact study covers the four main Energy consuming sectors: transportation, manufacturing, power generation, and residential. Previously published four case studies on passenger cars, trucks and buses, paper machines and the mining industry were included in our detailed calculations as reference data in our current analyses. The following can be concluded: Fifty years ago, wear and wear-related failures were a major concern for UK industry and their mitigation was considered to be the major contributor to potential economic savings by as much as 95% in ten years by the development and deployment of new tribological solutions. The corresponding estimated savings are today still of the same orders but the calculated contribution to cost reduction is about 74% by friction reduction and to 26% from better wear protection. Overall, wear appears to be more critical than friction as it may result in catastrophic failures and operational breakdowns that can adversely impact productivity and hence cost.

  • Global Energy Consumption due to friction in trucks and buses
    Tribology International, 2014
    Co-Authors: Kenneth Holmberg, Peter Andersson, Nilsolof Nylund, Kari Makela, A Erdemir
    Abstract:

    Abstract In this paper, we report the Global fuel Energy Consumption in heavy-duty road vehicles due to friction in engines, transmissions, tires, auxiliary equipment, and brakes. Four categories of vehicle, representing an average of the Global fleet of heavy vehicles, were studied: single-unit trucks, truck and trailer combinations, city buses, and coaches. Friction losses in tribocontacts were estimated by drawing upon the literature on prevailing contact mechanics and lubrication mechanisms. Coefficients of friction in the tribocontacts were estimated based on available information in the literature for four cases: (1) the average vehicle in use today, (2) a vehicle with today׳s best commercial tribological technology, (3) a vehicle with today׳s most advanced technology based upon recent research and development, and (4) a vehicle with the best futuristic technology forecasted in the next 12 years. The following conclusions were reached: • In heavy duty vehicles, 33% of the fuel Energy is used to overcome friction in the engine, transmission, tires, auxiliary equipment, and brakes. The parasitic frictional losses, with braking friction excluded, are 26% of the fuel Energy. In total, 34% of the fuel Energy is used to move the vehicle. • Worldwide, 180,000 million liters of fuel was used in 2012 to overcome friction in heavy duty vehicles. This equals 6.5 million TJ/a; hence, reduction in frictional losses can provide significant benefits in fuel economy. A reduction in friction results in a 2.5 times improvement in fuel economy, as exhaust and cooling losses are reduced as well. • Globally a single-unit truck uses on average 1500 l of diesel fuel per year to overcome friction losses; a truck and trailer combination, 12,500 l; a city bus, 12,700 l; and a coach, 7100 l. • By taking advantage of new technology for friction reduction in heavy duty vehicles, friction losses could be reduced by 14% in the short term (4 to 8 years) and by 37% in the long term (8 to 12 years). In the short term, this would annually equal worldwide savings of 105,000 million euros, 75,000 million liters of diesel fuel, and a CO2 emission reduction of 200 million tones. In the long term, the annual benefit would be 280,000 million euros, 200,000 million liters of fuel, and a CO2 emission reduction of 530 million tonnes. • Hybridization and electrification are expected to penetrate only certain niches of the heavy-duty vehicle sector. In the case of city buses and delivery trucks, hybridization can cut fuel Consumption by 25% to 30%, but there is little to gain in the case of coaches and long-haul trucks. Downsizing the internal combustion engine and using recuperative braking Energy can also reduce friction losses. • Electrification is best suited for city buses and delivery trucks. The Energy used to overcome friction in electric vehicles is estimated to be less than half of that of conventional diesel vehicles. Potential new remedies to reduce friction in heavy duty vehicles include the use of advanced low-friction coatings and surface texturing technology on sliding, rolling, and reciprocating engine and transmission components, new low-viscosity and low-shear lubricants and additives, and new tire designs that reduce rolling friction.

  • Global Energy Consumption due to friction in paper machines
    Tribology International, 2013
    Co-Authors: Kenneth Holmberg, Roope Siilasto, Tarja Laitinen, Peter Andersson, Ari Jasberg
    Abstract:

    Abstract Calculations on the Global Energy Consumption used to overcome friction in paper machines in terms of friction in motors, transmissions, pumps, blowers, agitators, pipes and the roll systems are presented. The following was concluded: – The Energy consumed to overcome friction in a paper mill is in the range 15–25%. – Globally there were 8525 paper and paperboard machines in operation in 2012. One paper machine uses on an average 140 TJ of electrical Energy per year. Of this 32% is consumed to overcome friction, 36% is used for the paper production and mass transportation and 32% is other losses. – The friction losses in an average paper machine are in total 44.8 TJ per year, and they are distributed as 32% due to friction in water-lubricated sliding in seals, doctor blades and fabric/support contacts, 23% due to friction in elastohydrodynamic rolling contacts, 22% due to friction in elastohydrodynamic rolling–sliding contacts, 15% due to friction in oil-lubricated seals and 8% due to friction in hydrodynamically lubricated contacts. – Worldwide 105,000 GWh electrical power was used in 2009 to overcome friction in paper machines. This equals to 381,000 TJ of annual Energy Consumption. – By taking advantage of new technology for friction reduction in paper machines, friction losses could be reduced by 11% in the short term (about 10 years), and by 23.6% in the long term (20–25 years). This would equal to annual worldwide economic savings of 2000 million euros and 4200 million euros; electricity savings of 36,000 and 78,000 GWh; and CO2 emission reduction of 10.6 million and 22.7 million tonnes. Potential mechanisms to reduce friction in paper machines include the use of low-friction and highly durable coatings, surface engineering including texturing, low-viscosity and low-shear lubricants and fluids, novel additives, new materials in seals, doctorblades and fabrics, as well as new designs.

  • Global Energy Consumption due to friction in passenger cars
    Tribology International, 2012
    Co-Authors: Kenneth Holmberg, Peter Andersson, A Erdemir
    Abstract:

    Abstract This study presents calculations on the Global fuel Energy Consumption used to overcome friction in passenger cars in terms of friction in the engine, transmission, tires, and brakes. Friction in tribocontacts was estimated according to prevailing contact mechanisms such as elastohydrodynamic, hydrodynamic, mixed, and boundary lubrication. Coefficients of friction in the tribocontacts were estimated based on available information in the literature on the average passenger car in use today, a car with today’s advanced commercial tribological technology, a car with today’s best advanced technology based upon recent research and development, and a car with the best technology forecasted in the next 10 years. The following conclusions were reached: • In passenger cars, one-third of the fuel Energy is used to overcome friction in the engine, transmission, tires, and brakes. The direct frictional losses, with braking friction excluded, are 28% of the fuel Energy. In total, 21.5% of the fuel Energy is used to move the car. • Worldwide, 208,000 million liters of fuel (gasoline and diesel) was used in 2009 to overcome friction in passenger cars. This equals 360 million tonne oil equivalent per year (Mtoe/a) or 7.3 million TJ/a. Reductions in frictional losses will lead to a threefold improvement in fuel economy as it will reduce both the exhaust and cooling losses also at the same ratio. • Globally, one passenger car uses on average of 340 l of fuel per year to overcome friction, which would cost 510 euros according to the average European gas price in 2011 and corresponds to an average driving distance of 13,000 km/a. • By taking advantage of new technology for friction reduction in passenger cars, friction losses could be reduced by 18% in the short term (5–10 years) and by 61% in the long term (15–25 years). This would equal worldwide economic savings of 174,000 million euros and 576,000 million euros, respectively; fuel savings of 117,000 million and 385,000 million liters, respectively; and CO 2 emission reduction of 290 million and 960 million tonnes, respectively. • The friction-related Energy losses in an electric car are estimated to be only about half those of an internal combustion passenger car. Potential actions to reduce friction in passenger cars include the use of advanced coatings and surface texturing technology on engine and transmission components, new low-viscosity and low-shear lubricants and additives, and tire designs that reduce rolling friction.

A Habib - One of the best experts on this subject based on the ideXlab platform.

  • exploring the possible effect of anthropogenic heat release due to Global Energy Consumption upon Global climate a climate model study
    International Journal of Climatology, 2016
    Co-Authors: Bing Chen, Li Dong, Linling Chen, T Nakajima, A Habib
    Abstract:

    The high-resolution Global distribution of anthropogenic heat release (AHR), which is generated by human Energy Consumption, is estimated by means of applying satellite remote sensing. Additionally, it was considered into a Global climate model and the possible climatic effect of AHR is examined in this study. AHR is geographically concentrated and fundamentally correlates with economic activity in Global scale. The current mean AHR flux on the Global scale is approximately 0.03 W m−2; however, the flux reaches a level high enough to influence the regional climate in concentrated urban areas. Global climate model results indicate that AHR may disrupt the normal atmospheric circulation and could have an obvious effect on the surface temperature at middle and high latitudes in summer and winter over the Northern Hemisphere. The climatic effect of AHR differs in various seasons: the Global mean surface temperature could increase by approximately 0.02 K in boreal summer and by 0.10 K in boreal winter. With the continued development of the Global economy and urbanization, the climatic effect of AHR will become increasingly pronounced. The climatic effect of AHR should not be merely confined to the regional climate, AHR is a tiny but essential factor in Global climate and long-term climate change that should not be ignored.

Peter Andersson - One of the best experts on this subject based on the ideXlab platform.

  • Global Energy Consumption due to friction in trucks and buses
    Tribology International, 2014
    Co-Authors: Kenneth Holmberg, Peter Andersson, Nilsolof Nylund, Kari Makela, A Erdemir
    Abstract:

    Abstract In this paper, we report the Global fuel Energy Consumption in heavy-duty road vehicles due to friction in engines, transmissions, tires, auxiliary equipment, and brakes. Four categories of vehicle, representing an average of the Global fleet of heavy vehicles, were studied: single-unit trucks, truck and trailer combinations, city buses, and coaches. Friction losses in tribocontacts were estimated by drawing upon the literature on prevailing contact mechanics and lubrication mechanisms. Coefficients of friction in the tribocontacts were estimated based on available information in the literature for four cases: (1) the average vehicle in use today, (2) a vehicle with today׳s best commercial tribological technology, (3) a vehicle with today׳s most advanced technology based upon recent research and development, and (4) a vehicle with the best futuristic technology forecasted in the next 12 years. The following conclusions were reached: • In heavy duty vehicles, 33% of the fuel Energy is used to overcome friction in the engine, transmission, tires, auxiliary equipment, and brakes. The parasitic frictional losses, with braking friction excluded, are 26% of the fuel Energy. In total, 34% of the fuel Energy is used to move the vehicle. • Worldwide, 180,000 million liters of fuel was used in 2012 to overcome friction in heavy duty vehicles. This equals 6.5 million TJ/a; hence, reduction in frictional losses can provide significant benefits in fuel economy. A reduction in friction results in a 2.5 times improvement in fuel economy, as exhaust and cooling losses are reduced as well. • Globally a single-unit truck uses on average 1500 l of diesel fuel per year to overcome friction losses; a truck and trailer combination, 12,500 l; a city bus, 12,700 l; and a coach, 7100 l. • By taking advantage of new technology for friction reduction in heavy duty vehicles, friction losses could be reduced by 14% in the short term (4 to 8 years) and by 37% in the long term (8 to 12 years). In the short term, this would annually equal worldwide savings of 105,000 million euros, 75,000 million liters of diesel fuel, and a CO2 emission reduction of 200 million tones. In the long term, the annual benefit would be 280,000 million euros, 200,000 million liters of fuel, and a CO2 emission reduction of 530 million tonnes. • Hybridization and electrification are expected to penetrate only certain niches of the heavy-duty vehicle sector. In the case of city buses and delivery trucks, hybridization can cut fuel Consumption by 25% to 30%, but there is little to gain in the case of coaches and long-haul trucks. Downsizing the internal combustion engine and using recuperative braking Energy can also reduce friction losses. • Electrification is best suited for city buses and delivery trucks. The Energy used to overcome friction in electric vehicles is estimated to be less than half of that of conventional diesel vehicles. Potential new remedies to reduce friction in heavy duty vehicles include the use of advanced low-friction coatings and surface texturing technology on sliding, rolling, and reciprocating engine and transmission components, new low-viscosity and low-shear lubricants and additives, and new tire designs that reduce rolling friction.

  • Global Energy Consumption due to friction in paper machines
    Tribology International, 2013
    Co-Authors: Kenneth Holmberg, Roope Siilasto, Tarja Laitinen, Peter Andersson, Ari Jasberg
    Abstract:

    Abstract Calculations on the Global Energy Consumption used to overcome friction in paper machines in terms of friction in motors, transmissions, pumps, blowers, agitators, pipes and the roll systems are presented. The following was concluded: – The Energy consumed to overcome friction in a paper mill is in the range 15–25%. – Globally there were 8525 paper and paperboard machines in operation in 2012. One paper machine uses on an average 140 TJ of electrical Energy per year. Of this 32% is consumed to overcome friction, 36% is used for the paper production and mass transportation and 32% is other losses. – The friction losses in an average paper machine are in total 44.8 TJ per year, and they are distributed as 32% due to friction in water-lubricated sliding in seals, doctor blades and fabric/support contacts, 23% due to friction in elastohydrodynamic rolling contacts, 22% due to friction in elastohydrodynamic rolling–sliding contacts, 15% due to friction in oil-lubricated seals and 8% due to friction in hydrodynamically lubricated contacts. – Worldwide 105,000 GWh electrical power was used in 2009 to overcome friction in paper machines. This equals to 381,000 TJ of annual Energy Consumption. – By taking advantage of new technology for friction reduction in paper machines, friction losses could be reduced by 11% in the short term (about 10 years), and by 23.6% in the long term (20–25 years). This would equal to annual worldwide economic savings of 2000 million euros and 4200 million euros; electricity savings of 36,000 and 78,000 GWh; and CO2 emission reduction of 10.6 million and 22.7 million tonnes. Potential mechanisms to reduce friction in paper machines include the use of low-friction and highly durable coatings, surface engineering including texturing, low-viscosity and low-shear lubricants and fluids, novel additives, new materials in seals, doctorblades and fabrics, as well as new designs.

  • Global Energy Consumption due to friction in passenger cars
    Tribology International, 2012
    Co-Authors: Kenneth Holmberg, Peter Andersson, A Erdemir
    Abstract:

    Abstract This study presents calculations on the Global fuel Energy Consumption used to overcome friction in passenger cars in terms of friction in the engine, transmission, tires, and brakes. Friction in tribocontacts was estimated according to prevailing contact mechanisms such as elastohydrodynamic, hydrodynamic, mixed, and boundary lubrication. Coefficients of friction in the tribocontacts were estimated based on available information in the literature on the average passenger car in use today, a car with today’s advanced commercial tribological technology, a car with today’s best advanced technology based upon recent research and development, and a car with the best technology forecasted in the next 10 years. The following conclusions were reached: • In passenger cars, one-third of the fuel Energy is used to overcome friction in the engine, transmission, tires, and brakes. The direct frictional losses, with braking friction excluded, are 28% of the fuel Energy. In total, 21.5% of the fuel Energy is used to move the car. • Worldwide, 208,000 million liters of fuel (gasoline and diesel) was used in 2009 to overcome friction in passenger cars. This equals 360 million tonne oil equivalent per year (Mtoe/a) or 7.3 million TJ/a. Reductions in frictional losses will lead to a threefold improvement in fuel economy as it will reduce both the exhaust and cooling losses also at the same ratio. • Globally, one passenger car uses on average of 340 l of fuel per year to overcome friction, which would cost 510 euros according to the average European gas price in 2011 and corresponds to an average driving distance of 13,000 km/a. • By taking advantage of new technology for friction reduction in passenger cars, friction losses could be reduced by 18% in the short term (5–10 years) and by 61% in the long term (15–25 years). This would equal worldwide economic savings of 174,000 million euros and 576,000 million euros, respectively; fuel savings of 117,000 million and 385,000 million liters, respectively; and CO 2 emission reduction of 290 million and 960 million tonnes, respectively. • The friction-related Energy losses in an electric car are estimated to be only about half those of an internal combustion passenger car. Potential actions to reduce friction in passenger cars include the use of advanced coatings and surface texturing technology on engine and transmission components, new low-viscosity and low-shear lubricants and additives, and tire designs that reduce rolling friction.