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VDI Wissensforum GmbH - Reifen – Fahrwerk – Fahrbahn

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VDI Wissensforum GmbH (Hrsg.)

Reifen – Fahrwerk – Fahrbahn

Reihe: VDI-Berichte

Band 2398 2022

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V. Yordanov, L. Eckstein Continuous Estimation of the Local Friction Value Potential based on Tyre Acoustic Data S. 83-96

„… Continuous Estimation of the Local Friction Value Potential based on Tyre Acoustic Data Ventseslav …” „… systems, at any driving situation, is the accurate and continuous monitoring of the local fric-tion value …” „… between the tyre sound pressure and the local friction value poten-tial are analysed based on power …”

Titelei/Inhaltsverzeichnis S. I-VIII

„… ReifenentwicklungContinuous Estimation of the Local Friction Value Potential based on Tyre Acoustic Data . . . . .83V …”

doi.org/10.51202/9783181023983

VDI Wissensforum GmbH - International Conference on Gears 2017

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VDI Wissensforum GmbH (Hrsg.)

International Conference on Gears 2017

Reihe: VDI-Berichte

Band 2294 2017

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J. Thomas, C. Wirth Determination and improvement of bevel gear efficiency by means of loaded TCA S. 707-718

„… local sliding velocities and local normal forces can be calculated and as soon as local friction …” „… coefficients are known (see following chapter), local friction forces as well. Finally “LokAna” calculates for …” „… shows the formula and its influence parameters. Eq. 10 where i [-] is the local friction …”

M. Oehler, B. Magyar, B. Sauer A new standardizable calculation method to predict the efficiency of worm gear drives S. 363-372

„… friction follows, which corresponds to the local friction coefficient between the gears. A more precise …” „… incoming coefficient of friction comes down to a limit value. This approach is outlined in Figure 6 and …” „… gearing can be investigated in a variety of ways. The target variables are, among other things, the local …”

L. Geng, N. Mimi, L. Lan, Z. Ying, W. Liyan Mesh stiffness of cylindrical gear including tooth surface – Friction based on FEA method S. 807-814

„… be seen that tooth friction and oil film can decrease the value of mesh stiffness. a) 0.0 0.2 …” „… Mesh Stiffness of Cylindrical Gear Including Tooth Surface Friction Based on FEA Method Liu …” „… Controls, Northwestern Polytechnical University, Xi’an, China Abstract The tooth friction and oil film …”

N. Sagraloff, M. Hein, T. Tobie, K. Stahl Practical use of micropitting test results according to FVA 54/7 for calculation of micropitting load capacity acc. to ISO/TR 15144-1 S. 143-152

„… pitting damages. Calculation models for estimating the local material removal as a function of the …” „… determinate the local risk of micropitting. Based on this calculation model, optimal tooth flank …” „… ). This SKS-value is defined as the load stage, in which the defined failure criterion (profile form …”

J. Cathelin, R. Janssen Material data for advanced plastic gear simulation S. 1553-1564

„… distance correction Friction coefficient [-] Gear temperature Wear coefficient [mm3/N.m] Flank wear …” „… , the yield stress value should not be exceeded at the gear tooth root because permanent deformation of …” „… the teeth can occur, creating local contact interferences, which can lead to early failure …”

C. Brecher, C. Löpenhaus, F. Goergen, D. Mevissen Crack propagation analysis of pitting damages of high-strength material systems in gear applications S. 281-292

„… expected at a local exceedance of the material stress state of the value one. Thus, the current local …” „… detailed analysis of pitting characteristics and on the comparison with local stress components …” „… local stress components extends the knowledge of contact fatigue progression and provides a basis for …”

S. Stoyanov, V. Dobrev, A. Dobreva Investigating dynamic behavior of planetary gear trains through the systematic approach S. 197-208

„… mesh the contact lines and surfaces with a local step, which has a small value of the seed size. This …” „… and the same part – global and local. This means that the designer can mesh the entire part with a …” „… global step, which has a great value of the seed step. Together with this global step, the designer can …”

T. Frech, C. Löpenhaus, F. Klocke Influence of the contact conditions in cold rolling on the density profile of powder metallurgical (PM) gears S. 1265-1276

„… , therefore, the local mechanical properties of PM gears. The process parameters infeed, equivalent contact …” „… to increase their local density and, therefore, the load-carrying capacity [2]. PM gears are …” „… stress states on the material deformation [4, 5, 6]. Since friction does not influence the normal …”

D. Krüger, E. Leidich, I. Römhild, R. Heß, H. Linke Geometry, pitting and tooth root capacity of asymmetric gears S. 751-768

„… stress, the coefficient of friction, the direction and magnitude of sliding speed as well as the effect …” „… loaded at the highest point of single tooth contact and the friction is neglected. The maximum of the …” „… tooth root thickness and the bending arm. The calculation of the local maximum tensile stress in the …”

C. Brecher, C. Löpenhaus, R. Greschert Influence of the grinding process on the formation of boundary layers on gears S. 1427-1438

„… economical design of gears. 1. Introduction Gear transmissions are usually run under mixed friction, i.e …” „… arithmetic mean is calculated as representative value. The measurement parameters are chosen in accordance …” „… 0.21 0.20 Ra value increased Specific Material Removal Rate Q‘w = ae·vf [mm³/mm·s] Axial feed rate vf …”

J. J. Liou, S. Rakuff The development of worm drives S. 503-516

„… , local tooth friction and oil churning have to be obtained through the corresponding tribological …” „… ; therefore, the load capacity for worm drives is relatively limited and friction greatly affects the …” „… in much lower friction forces that cannot be found in other metal combinations. It also results in …”

B. Černe, D. Zorko, J. Duhovnik Semi-analytical method for the prediction of the flank temperatures of polymer gears during running S. 1611-1624

„… meshing cycle begins. The flash temperature is on the other hand the local temperature rise beneath the …” „… geometry parameters Parameter Symbol [unit] Value Transmission i [/] 1 Module m [mm] 1 Number of teeth …” „… value). We considered here two polymer materials, i.e. POM and PA66, where in correlation to the tests …”

R. Meissner, M. Liewald, T. Benkert, M. Hiller, W. Volk Multi-component gearwheels and their manufacturing processes S. 1299-1306

„… contact describes the tangential behavior using a friction value of 0.1. There are two boundary …” „… from high strength steel supports the high local loads mentioned above and a lightweight wheel body …” „… positive values would increase this value [3]. Further investigations on the influence of clean shear …”

M. Kanters, B. van Wissen, R. Nickel Relevant tribological testing method for high performance plastic gears S. 1507-1518

„… past few years towards a more specialized, higher value-added businesses in Automotive, Electrical and …” „… sliding wear. To study specific tribological properties, wear and friction measurements are performed on …” „… friction behavior in relevant plasticplastic material pairs. This showed that the ranking of different …”

S.-J. Tsai, L.-C. Chang, C.-H. Huang Design of cycloid planetary gear drives with tooth number difference of two – a comparative study on contact characteristics and load analysis S. 61-74

„… , 3] and also the complete tooth contact considering the bearing stiffness and the friction [8]. The …” „… . Table 3: Essential gearing data for numerical analysis Items / symbols value remarks Pitch circle …” „… local extremum on the tip. The pin radius has almost no influences (Figure 8). The eccentricity e …”

doi.org/10.51202/9783181022948

VDI Wissensforum GmbH - International Conference on Gears 2022

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International Conference on Gears 2022

Reihe: VDI-Berichte

Band 2389 2022

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A. Gebhard, W. Kassem, M. Oehler Cylinder-on-ring model wear tests as an input data source for the simulation of friction and wear of plastic gears S. 1133-1148

„… value for the coefficient of friction is integrated according to the local conditions in the tooth …” „… computational grid. With the local solid friction force and the local friction distance , the local wear volume …” „… parameter sets the range of individual friction coefficients was at least 40% of the mean value of the …”

K. Daubach, M. Oehler, B. Sauer Wear simulation of worm gears based on an energetic approach S. 329-342

„… tribological calculation to determine the local solid tooth friction and wear. The calculation is iterated with …” „… asperities are separated from each other by a lubricant film (fluid friction). Depending on the local …” „… tribological conditions, boundary or fluid friction predominates at one point. For a local wear calculation …”

B. van Wissen, M. Kanters, F. Mitsuzuka, K. Iwanaga, M. Meuwissen, A. Hasanovic Predicting static and fatigue performance of fiber reinforced plastic gears S. 1083-1098

„… performed within a range of environmental temperatures. Due to friction the local tooth temperature …” „… analysis, including the local fiber orientation in combination with the intrinsic material behavior, is …” „… composition, excellent wear and friction properties and retains its mechanical properties for a long period of …”

P. Rodel, R. Spieler, M. Indenbirken, T. Nuisl Holistic friction optimization of transmissions – a significant contribution for sustainability S. 731-744

„… Holistic friction optimization of transmissions A significant contribution for sustainability …” „… are faced with new challenges. The topic friction optimization gains higher importance during …” „… required. The only means to achieve cost and time efficient holistic friction optimization is the usage of …”

A. Eric, D. Olveda, T. Froschmeier, V. Schulze Local pitting fatigue concept with EHL simulation for case hardened gears in electrical drives S. 133-144

„… Local Pitting Fatigue Concept with EHL Simulation for Case Hardened Gears in Electrical Drives A …” „… experience and experiments. Because of this, the authors developed a local fatigue concept for the pitting …” „… evaluation of case hardened gears which compares the local stresses in the gear subsurface with the local …”

B. Reetz, T. Munch, W. Kappeler Challenges for lead-free brass alloys in worm gears S. 1467-1488

„… variation of the friction value on the tooth flank surface. The highest friction values given in Fig. 3 …” „… (castability, hot workability, machinability). On the other hand, they need to function under wear, friction …” „… to increasing wear under high loadings. This wear is further driven by the generation of friction …”

P. H. O. Teixeira, J. Brimmers, T. Bergs Consideration of micro-interaction in the modeling of generating gear grinding processes S. 1517-1528

„… grain will contain a local zero coordinate point, which is based on the position of grain within the …” „… considered. The grain positioning is performed based on the information of each individual grain local zero …” „… . In the diagram, it is possible to see that each grain has a different average value of cross-section …”

P. Tenberge, J. Vorgerd, L. Gondecki 2-disc tribometer for various tests on sliding/rolling contacts with tribological loads such as in tooth flank contacts S. 145-156

„… tribometer, all relevant load components can be reproduced in their local and timely courses very …” „… , the local power losses and energy inputs lead to complex, mutually interacting wear and fatigue …” „… mechanisms [2 ... 5], as shown in Fig. 2. Thin lubricating films reduce the friction and, by the influence of …”

N. Tros, J. Brimmers, T. Bergs Approach for multiscale modeling the thermomechanical tool load in gear hobbing S. 1489-1502

„… based on local uncut chip geometries. The result is a multiscale model for describing the …” „… . It can therefore be assumed that the material model is also valid for the present case. The friction …” „… at the tool-chip interface was described by the COULOUMB friction law at a constant coefficient of …”

K. Stahl, T. Tobie, C. M. Illenberger Standardized methods of load capacity calculation of plastic gears S. 1173-1180

„… gear. Grease lubrication is one possibility to reduce friction in the gear contact and thus minimize …” „… friction losses in order to increase the possible drive power. Operation under oil-lubricated conditions is …” „… by means of lower friction losses due to lubrication but heat is also removed from the gear contact …”

A. Baumann, B. Bertsche Coefficient of friction behavior of gear oils and significance for the meshing process of spur gears S. 745-762

„… Coefficient of friction behavior of gear oils and significance for the meshing process of spur …” „… procedure for determining the coefficient of friction is used in the following to enable a further …” „… teeth, rolling friction occurs in the gear pair meshing along the line of action due to the variation in …”

W. Wagner, S. Schumann, B. Schlecht Enhanced loaded tooth contact analysis of hypoid gears within a multi-body-system simulation S. 357-370

„… contact and therefore the reaction forces under consideration of friction. This leads to a simplification …” „… the local load distribution on the contact flank based on the relative position of pinion and gear as …” „… distribution = ( ) from the local penetrations = ( ) , the ( × ) compliance matrix = ( ) , is required. This …”

P. Mahendra Rao, S. Foletti, L. Bonaiti, C. Gorla, S. Beretta, F. Concli Mode III threshold under rolling contact fatigue and development of a test gearbox for planet gears S. 499-510

„… the results with the full-scale test articles of the experimental campaign. Friction has been …” „… analysis has been performed in a 2D plain strain non-linear condition (CPE8), with local and global seed …” „… instantaneous hydrostatic component of the stress tensor; and ? ? is the instantaneous value of the Tresca …”

J. Koenig, D. Kehle, K.-P. Heinzle Investigation of the failure mechanisms of plastic materials with and without fiber reinforcement S. 1269-1280

„… calculated the local temperature increase from a friction and deformation part, and according to Hachmann and …” „… that, in the case of oil-lubricated gearings, friction-reducing additives such as PTFE and graphite …” „… friction-reducing additives such as PTFE in PA66 lead to reduced frictional power and an associated lower tooth …”

K. J. Winkler, T. Tobie, K. Stahl Influence of grinding zones on the tooth root bending strength of case carburized cylindrical gears S. 287-304

„… increasing impact depending on the local geometry of a grinding notch, the following material parameters can …” „… influencing the tooth root bending strength. Due to micro-notch effects, the surface roughness leads to local …” „… . Table 1: Geometry data and geometry draft of the test gear Description Symbol Unit Value Test gear …”

L. Hildebrand, F. Dangl, M. Sedlmair, T. Lohner, K. Stahl CFD analysis on the oil flow of a gear stage with guide plate S. 677-694

„… engagement of gears. The local remeshing method is used, whereby the mesh is locally renewed when a certain …” „… with a mean acceleration value of a = 40 m/s² was used. Hereby the numerical stability of the …” „… vt = 10 m/s the same acceleration value of the previous simulation (vt = 7 m/s) was used, resulting …”

B. Legrady, M. Taesch, G. Tschirschnitz, C. F. Mieth Prediction of churning losses in an industrial gear box with spiral bevel gears using the smoothed particle hydrodynamic method S. 651-664

„… capable of evaluating the local churning loss of each component is developed. Thereby, the pinion with its …” „… is required to decrease friction between the contacting gears and to absorb the dissipated heat from …” „… expressions leads to a local formulation of the power losses by means of viscous and pressure induced …”

H.-J. Dennig, L. Zumofen, A. Kirchheim, S. Winterberg, D. Stierli Increasing the safety against scuffing of additive manufactured gear wheels by internal cooling channels S. 1345-1364

„… the following article. The tooth flank is primarily exposed to pressure and friction with simultaneous …” „… result of the increased stress, local temperature increases occur, which leads to the lubricant film …” „… test gears for the FZG scuffing test Dimension Symbol Numerical Value Unit Centre distance a 91.5 mm …”

doi.org/10.51202/9783181023891

VDI Wissensforum GmbH - International Conference on Gears 2023

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VDI Wissensforum GmbH (Hrsg.)

International Conference on Gears 2023

Reihe: VDI-Berichte

Band 2422 2023

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M. J. Herberger, F. Rudolph, B. Sievers Efficient concepts for high ratio angular gearboxes S. 801-814

„… transmit-ted normal force, the occurring sliding speed distribution and the local coefficient of friction are …” „… determining the local coefficient of friction, see [7], [9], [10]. Here, the approach according to FVA 519 [10 …” „… for the load-dependent gearing losses. A comparison of calculation methods shows, that the local …”

E. Grabovic, A. Artoni, M. Gabiccini, E. Ciulli Exploration of trade-offs between NVH and efficiency in bevel gear design S. 853-880

„… ] provided an accurate estimation of the local friction coefficient of spur gears under transient …” „… Minimizing NVH and friction-induced power losses is becoming paramount in the design of geared transmissions …” „… . estimation of the elasto-hydrodynamic lubrication (EHL) friction coefficient; Numerous models and methods …”

J. Vorgerd, P. Tenberge, M. Steinrötter Scuffing load carrying capacity of high-speed gears with an isotropic superfinished surface S. 227-242

„… by friction in the local slide-roll contacts due to gear damage and thermal heat emission. The local …” „… increasingly used to reduce friction in the local slide-roll contacts. However, the current calculation …” „… friction. In the scope of this work a local friction model according to LÖPENHAUS [LÖPE15] was modified to …”

B. Devaux, C. Hamon, S. Montani Evaluation of specialty polymer performances in gear applications and the bias between modeling and testing approaches S. 1515-1532

„… .- Friction coefficient: 0.35In DIGIMAT, a commercial software, we can map the local fiber orientation tensor …” „… times and the weight loss being computed on the mean value: VDI-Berichte Nr. 2422, 2023 1519- Amodel PPA …” „… definition of the below parameters for each mesh element, according to its local fiber orientation: - The …”

T. Schmidt, B. Neubauer, D. Merk White Etching Cracks (WECs) on gears of E-Axle applications S. 257-268

„… specific friction energy (ea,kin), high mixed friction conditions, high Hertzian pressure and a critical …” „… to low viscosity in combination with friction modifying additives. Therefore, the Schaeffler derivate …” „… correlates with fracture origin in Fig. 3. Unfortunately point A and E is not useable due to local geometric …”

S. Sklenak, D. Mevissen, J. Brimmers, C. Brecher, B. Lenz, A. Mehner Analysis of Load Cycles and Local Wear of Dry and Solid-Lubricated Gears S. 727-740

„… Analysis of Load Cycles and Local Wear of Dry and Solid-Lubricated Gears Sebastian Sklenak M. Eng …” „… can be found. A distinction can be made between wear of the solid lubricant layer, local layer failure …” „… friction-reducing effect (Fig. 1). In addition to extreme operating conditions, hygiene regulations, such as those …”

M. Yilmaz, M. Ayar, F. Zerulli, K. Humm, J. König, B. Schwarz Gearbox efficiency of eDrives: correlation between measurement and calculation of load-dependent torque losses S. 985-994

„… gear coefficient of friction μmz according to Schlenk (3). The necessary lubricant factor XL value for …” „… of friction μmz and the geometric tooth loss factor HV(L)according to formula (3) are necessary. The …” „… mean gear coefficient of friction as tribological influence can be calculated with the friction …”

M. Geitner, S. Preintner, T. Tobie, K. Stahl Simulation Study on the Tribological Characteristics in the Meshing Contact in the Context of the Load Carrying Capacity Calculation of Internal Gears with Unbalanced Sliding Conditions S. 429-450

„… internal gears remains to be checked. Approaches for the local gear coefficient of friction also need to be …” „… this calculation step serves as a starting value for the following calculation of an isothermal EHL …” „… ∙| | ∙.∙𝑋1.2 ∙ 𝑋 . (3)* Here, the mean coefficient of friction 𝜇 is calculated according to Schlenk [21 …”

B. van Wissen, L. Pastukhov, F. Mitsuzuka, K. Iwanaga, A. Hasanovic NVH performance of thermoplastic gears: modelling and measuring S. 1389-1402

„… were performed at an ambient temperature of 23°C. Due to friction however the local teeth temperature …” „… . This polyamide-based grade has, due to its unique composition, excellent wear and friction properties …” „… modulus, lower hardness and higher damping value polymer gear applications generate less noise compared to …”

W. Ramdane, C. Changenet, S. S. Ouali, C. Chevrel-Fraux, P. Casanova Thermal model of a planetary gear set using an isothermal approach S. 451-466

„… power losses, associated with gear tooth friction and bearing friction; ii) load independent power …” „… losses, generated by sealing friction, bearing hydrodynamic losses and gear churning. Those power losses …” „… friction dissipation [1]. Concerning load independent power losses, different experimental methods [2][3][4 …”

F. Mieth, D. Tazir Local load capacity analysis for the design of a balanced flank modification for cylindrical gears according to bevel gear procedures S. 927-944

„… friction and film thickness, and geometry coefficients like sliding speeds. In addition, the local load …” „… Local load capacity analysis for the design of a balanced flank modification for cylindrical gears …” „… possible types of damage for bevel gears is only possible with the aid of local load capacity analyses [3 …”

A. Drechsel, J. Pellkofer, K. Stahl Transferability of the scuffing load capacity of gear oils determined on spur gears to hypoid gears S. 881-896

„… hypoid scuffing test method. Due to the difference in the absolute value of the friction coefficient for …” „… which the tooth flank surfaces are welded due to an excessively high local temperature occurring during …” „… , Reichert-Friction wear scale, Four-Ball-Fig. 1: Scuffing marks at the drive flank of a hypoid gear [4] VDI-Berichte …”

L. Becker, P. Tenberge Crossed helical gears – simulative studies and experimental results on non-involute geometries S. 1499-1514

„… ) in case of a positive value (also negative values for a convex circular contour are possible, but …” „… of the value u, like the points on the tooth flank before. To calculate the flank pressure …” „… properties, the friction coefficient zm was assumed to be constant and comparable to similar materials …”

B.-S. Kim, D. Im, J.-H. Park, W.-J. Chung, Y.-J. Park Development of Optimal Design Program for Macro-Geometry of Planetary Gear Set using Multi-Objective Optimization Algorithm S. 1181-1194

„… mesh friction loss was calculated as follows through the method defined in AGMA 6123 [10]. 𝑃 𝑃 𝑃 𝑁 …” „… algorithms were used, it was confirmed that they fell into the local minimum and converged to the point with …” „… IGD value converged slowly according to the number of generations, but in the MOMBI-II and RPEA …”

F. Concli, M. N. Mastrone Latest advancements in the lubrication simulations of geared systems: a technology ready for industrial applications S. 499-518

„… load-dependent power losses, i.e. the one related to friction and proportional to the transmitted load. Those …” „… mesh can result in a higher computational cost. The remeshing could be either ”local” or ”global …” „… ” depending regions enabled for re-meshing. In the Local Remeshing Approach (LRA), only the elements having …”

P. E. Schnetzer, J. Pellkofer, K. Stahl Calculation method for wear of steel-bronze rolling-sliding contacts relating to worm gears S. 907-926

„… rest rig under boundary and mixed lubrication to analyze the local coefficient of friction of a worm …” „… investigations in literature. Oehler et al. [6] investigate the friction of steel-bronze contacts on a twin-disk …” „… friction and wear processes exist in the literature. The currently available calculation methods usually …”

M. Vivet, A. Rezayat, J. Verhoogen, K. Kucukcoskun, S. Donders Numerical analysis of bevel gear transmission acoustic emission using a 3D gear contact force model within a multibody system dynamics simulation environment S. 689-702

„… damping gear contact force, and a Coulomb-based friction force [7].Accurate geometry. A set of procedures …” „… approximates the gear pair’s contact deformation as the sum of a global and a local deformation component …” „… and teeth) deflection field due to a contact load but omits the local contact deformation due to this …”

A. Wallinger, R. Vonderschmidt, S. Vonderschmidt Lubricant Free Transmissions for the food industry – A Comparison S. 715-726

„… ; no friction, contactless. Solid lubricants and additives contained in the plastic allow dry running …” „… hardened steel gear wheel, was used as the VDI-Berichte Nr. 2422, 2023724value here. The nominal torque of …” „… most applications, this value is considered sufficient. The gear unit with plastic gears has only a …”

M. Willecke, J. Brimmers, C. Brecher Experimental Investigation of the load carrying capacity of beveloid gears with optimized flank topography S. 125-138

„… taking into account the local material and stress condition as well as the tooth flank micro geometry …” „… values has to be compared. The stress value of the tooth contact analysis equals the allowable stress FE …” „… friction losses within the system during operation, an electric motor is employed, ensuring a constant …”

doi.org/10.51202/9783181024225

VDI Wissensforum GmbH - 16. Internationale VDI-Tagung Reifen-Fahrwerk-Fahrbahn 2017

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VDI Wissensforum GmbH (Hrsg.)

16. Internationale VDI-Tagung Reifen-Fahrwerk-Fahrbahn 2017

Reihe: VDI-Berichte

Band 2296 2017

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F. Calabrese, C. Ludwig, M. Bäcker, A. Gallrein Parameter-Identifikation eines thermomechanischen Reifenmodells basierend auf Flachbahn-Messungen S. 57-76

„… energy losses due to damping, inner and outer friction. The local energy losses are uses directly as …” „… local heat sources in the thermal model. The friction is modeled temperature dependent (surface …” „… possible to estimate the value of the parameter (dµ/dT) relative to the friction decay with the …”

doi.org/10.51202/9783181022962

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