EN 14067-4:2005

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Railway applications - Aerodynamics - Part 4: Requirements and test procedures for aerodynamics on open trackŽelezniške naprave – Aerodinamika – 4. del: Zahteve in preskusni postopki pri aerodinamiki na odprti progiApplications ferroviaires - Aérodynamique - Partie 4 : Exigences et procédures d'essai pur l'aérodynamique a l'air libreBahnanwendungen - Aerodynamik - Teil 4: Anforderungen und Prüfverfahren für Aerodynamik auf offener StreckeTa slovenski standard je istoveten z:EN 14067-4:2005SIST EN 14067-4:2006en45.060.01ICS:SLOVENSKI
STANDARDSIST EN 14067-4:200601-marec-2006

EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 14067-4November 2005ICS 45.060.01 English VersionRailway applications - Aerodynamics - Part 4: Requirements andtest procedures for aerodynamics on open trackApplications ferroviaires - Aérodynamique - Partie 4 :Exigences et procédures d'essai pour l'aérodynamique àl'air libreBahnanwendungen - Aerodynamik - Teil 4: Anforderungenund Prüfverfahren für Aerodynamik auf offener StreckeThis European Standard was approved by CEN on 14 October 2005.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2005 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14067-4:2005: E

Relationship between this European Standard and the Essential Requirements of EU Directive 96/48/EC.31 Bibliography.32

Introduction Trains running on open track generate aerodynamic loads on objects and persons they pass. If trains are being passed by other trains, trains are also subject to aerodynamic loading themselves. The aerodynamic loading caused by a train passing an object or a person near the track, or when two trains pass each other, depends mainly on the following parameters:  running speed of the train(s);  distance between the object and the train(s);  geometry of the train(s);  geometry of the object;  ambient wind effects. Trains running on open track have to overcome a resistance to motion.

Key 1 Head of train passing 2 Tail of train passing Figure 1 — Pressure signal at a point on a vertical wall caused by train passing 5.2 Assessment by predictive formulae 5.2.1 General remarks and application When calculating the mechanical and fatigue strength of a structure, the aerodynamic loads to be taken into account shall be of an equivalent amplitude at the head, tail, and in the case of nose-to-nose coupled trains, at the coupler as well. This amplitude shall be the largest of the loads during the complete passing time of the train. These aerodynamic loads shall be applied in every case perpendicular to the surface of the structure. They are defined as characteristic pressure values. The following subclauses allow a determination of characteristic pressure values which are in line with those given graphically in EN 1991-2 but allow a wider range of application by use of formulae. It has to be emphasized that the given characteristic pressure values represent the maximum area-averaged (dynamic) loads on a structure. Since a train passing does not result in a static load, these characteristic values cannot be taken as maximum static loads. Fatigue calculations require additional information on the dynamic behaviour of the structure, the number of cycles, more detailed information on the dynamics of the train-induced pressure pulse, etc. 5.2.2 Flat vertical structures parallel to the tracks The following structures belong to this category:

Figure 2 — Load on flat vertical structures parallel to the tracks The characteristic values p1k of the distributed loads are determined from Equation (4). p112tr1k2Ckvpρ= (4) where Cp1 is the aerodynamic coefficient depending on the distance from track axis Y; k1 is a shape coefficient of the train. The factor Cp1 is obtained from Equation (5). ()02,025,05,22p1++=YC (5) for Y ≥ 2,3 m.

Figure 3 — Load on flat horizontal structures above the tracks The values p2k of the distributed loads are determined from Equation (6). p222tr2k2Ckvpρ= (6) Here, k2 takes the same values as k1 given in 5.2.2. The coefficient Cp2 is obtained from Equation (7). ()015,010,322p2+−=hC (7) where

Figure 4 — Load on flat horizontal structures close to the tracks Values p3k of the loads which depend on Y are determined from Equation (8). p332tr3k2Ckvpρ= (8) The coefficient Cp3 is given by Equation (9). ()015,025,05,12p3++=YC (9) p3k should be calculated for the structure considered as a function of the distance Y, to the axis of the nearest track.

Figure 5 — Load on mixed vertical and horizontal or inclined structures close to the tracks The equivalent loads are greater in this case than in the case of purely vertical or horizontal surfaces. These values shall be determined from Equation (4) in 5.2.2 except that the following distance should be used in Equation (5):

Figure 6 — Loads for vertical and horizontal surfaces of structures enclosing two tracks 5.2.7 Effect of wind on loads caused by the train If the effect of ambient wind has to be included in the estimate of the head pressure pulse during train passage, the wind speed component parallel to the track should be added to the train speed. 5.3 Assessment by numerical simulations 5.3.1 General remarks and application To assess aerodynamic pressure loading during the concept phase or for the purpose of parametric or comparative studies, the head pressure pulse may be calculated with reasonable accuracy using the potential flow assumption (as in a panel method code) when no sharp edges are present on the front of the train. Other numerical simulation methods, e.g. Reynolds Averaged Navier Stokes codes, may be used. 5.3.2 Requirements The calculation domain may be limited to the leading vehicle to calculate the effect of the head of the train and shall take into account all the relevant geometric characteristics of the shape of the front of the train. The influence of the ground shall be included, whereas the modelling of cavities (bogies, pantographs, inter-car gaps, etc., but excluding nose-to-nose connections) may be ignored. The simulation shall model the real distance between the structure and the track. A validation of the numerical simulation for the application shall be provided. The result should be shown independent of the size and resolution of the calculation domain. At the start of the simulation, the head of the train shall be in front of the structure by a distance equivalent to at least the length of the leading vehicle. At the end of the simulation, the head of the train shall have passed the structure by at least the length of the leading vehicle.
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