1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58atmospheric conditionsICS 43.020Road vehicles Road load Part 1: Determination under reference BRITI
2、SH STANDARDBS ISO 10521-1:2006BS ISO 10521-1:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 November 2006 BSI 2006ISBN 0 580 49593 0Amendments issued since publicationAmd. No. Date Commentscontract. Users are responsible for its corre
3、ct application.Compliance with a British Standard cannot confer immunity from legal obligations.National forewordThis British Standard was published by BSI. It is the UK implementation of ISO 10521-1:2006.The UK participation in its preparation was entrusted to Technical Committee MCE/22, Engines fo
4、r road vehicles.A list of organizations represented on MCE/22 can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a Reference numberISO 10521-1:2006(E)INTERNATIONAL STANDARD ISO10521-1First edition2006-10-01Road vehicles Road load
5、Part 1: Determination under reference atmospheric conditions Vhicules routiers Rsistance sur route Partie 1: Dtermination dans les conditions atmosphriques de rfrence BS ISO 10521-1:2006ii iiiContents Page Foreword iv Introduction v 1 Scope 1 2 Normative references 1 3 Terms and definitions .1 4 Req
6、uired overall measurement accuracy .2 5 Road-load measurement on road.3 5.1 Requirements for road test.3 5.1.1 Atmospheric conditions for road test3 5.1.2 Test road.3 5.2 Preparation for road test.4 5.2.1 Vehicle preparation4 5.2.2 Installation of instruments4 5.2.3 Vehicle preconditioning 5 5.3 Mea
7、surement of total resistance by coastdown method 5 5.3.1 Multi-segment method 5 5.3.2 Average deceleration method 8 5.3.3 Direct regression method .10 5.4 Onboard-anemometer based coastdown method11 5.4.1 Selection of speed range for road-load curve determination .12 5.4.2 Data collection .12 5.4.3
8、Vehicle coastdown.12 5.4.4 Determination of coefficients .12 5.4.5 Determination of total resistance.13 5.5 Measurement of running resistance by torquemeter method 13 5.5.1 Installation of torquemeter .13 5.5.2 Vehicle running and data sampling .13 5.5.3 Calculation of mean speed and mean torque .14
9、 5.5.4 Running resistance curve determination16 5.6 Correction to standard atmospheric conditions 16 5.6.1 Correction factors16 5.6.2 Road-load curve correction17 6 Road-load measurement by wind tunnel/chassis dynamometer .19 6.1 Aerodynamic drag measurement in wind tunnel .19 6.1.1 Requirements for
10、 wind tunnel19 6.1.2 Testing procedure19 6.1.3 Test result.19 6.2 Rolling resistance determination with chassis dynamometer19 6.2.1 Testing device19 6.2.2 Testing procedure20 6.2.3 Test results.21 6.3 Total-resistance calculation .21 6.4 Total-resistance curve determination22 Annex A (informative) E
11、xamples of onboard-anemometer calibration procedure.23 Annex B (informative) Examples of dynamometer-measured rolling-resistance correction method26 BS ISO 10521-1:2006iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO mem
12、ber bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmen
13、tal and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Direc
14、tives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodi
15、es casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 10521-1 was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommi
16、ttee SC 5, Engine tests. This first edition, together with ISO 10521-2, cancels and replaces ISO 10521:1992, which has been technically revised. ISO 10521 consists of the following parts, under the general title Road vehicles Road load: Part 1: Determination under reference atmospheric conditions Pa
17、rt 2: Reproduction on chassis dynamometer BS ISO 10521-1:2006vIntroduction It is known that wind gives much influence to vehicle road-load measurement on test roads. Therefore, no international standards or national standards/regulations allowed conducting on-road tests under windy (e.g. 3 m/s or mo
18、re) conditions in terms of measurement accuracy. In this standard, wind effect correction methodology is newly introduced into the conventional coastdown method and torquemeter method, and it offers wider (up to wind speed of 10 m/s) opportunity of on-road tests. In addition, more realistic road loa
19、d can be simulated even under lower wind conditions. This part of ISO 10521 also adopts the off-road road-load measurement method as the comparable alternative. The method is based on the separation of the total road load into two components, aerodynamic drag and rolling resistance, where the former
20、 is measured in a wind tunnel and the latter with a chassis dynamometer. This alternative enables the standard users to carry out road-load measurement regardless of atmospheric conditions or other requirements necessary for the on-road test. It is not the scope of this standard to define all requir
21、ements of wind-tunnel design or test practice. Nevertheless, the standard users are encouraged to conduct the measurement with state-of-the-art wind-tunnel technologies and to respect the highest quality management standards such as ISO 17025, so as to secure the measurement reliability and repeatab
22、ility. In view of accessibility of the standard, International Standard ISO 10521 is divided into two parts in this second edition in order to provide two separate standards for the two different technical aspects, determination of road load and reproduction of road load on chassis dynamometer. BS I
23、SO 10521-1:2006blank1Road vehicles Road load Part 1: Determination under reference atmospheric conditions 1 Scope This part of ISO 10521 specifies methods of determining the road load of road vehicles for subsequent test purposes, for example, fuel consumption tests or exhaust emission measurements.
24、 This determines the road load of a vehicle running on a level road under reference atmospheric conditions. It is achieved by either the coastdown method, the torquemeter method or the wind-tunnel/chassis-dynamometer method. This part of ISO 10521 is applicable to motor vehicles, as defined in ISO 3
25、833, up to a gross vehicle mass of 3 500 kg. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any am
26、endments) applies. ISO 3833, Road vehicles Types Terms and definitions 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 3833 and the following apply. 3.1 total resistance total force-resisting movement of a vehicle, measured either by the coastdown me
27、thod or by the wind-tunnel/chassis-dynamometer method, including the friction forces in the drive-train 3.2 running resistance torque-resisting movement of a vehicle, measured by the torquemeter installed in the drive-train of a vehicle, including the friction torque in the drive-train downstream of
28、 the torquemeter 3.3 road load general meaning of the force or torque which opposes the movement of a vehicle, including total resistance and/or running resistance 3.4 aerodynamic drag resistance of the air to the motion of a vehicle BS ISO 10521-1:20062 3.5 rolling resistance opposing force in the
29、drive-train, axles and tyres to the motion of a vehicle 3.6 reference speed a vehicle speed at which a chassis-dynamometer load is verified 3.7 reference atmospheric conditions atmospheric conditions of the following values, to which the road-load measurement results are corrected: a) atmospheric pr
30、essure: p0= 100 kPa, unless otherwise specified by regulations; b) atmospheric temperature: t0= 293 K, unless otherwise specified by regulations; c) dry air density: 0= 1,189 kg/m3, unless otherwise specified by regulations; d) wind speed: 0 m/s. 3.8 stationary anemometry measurement of wind speed a
31、nd direction with an anemometer at a location and height above road level alongside the test road where the most representative wind conditions will be experienced 3.9 onboard anemometry measurement of wind speed and direction with an anemometer appropriately installed to the test vehicle 3.10 wind
32、correction correction of the effect of wind on road load, which is achieved either by stationary or by onboard anemometry 3.11 aerodynamic stagnation point point on the surface of a vehicle where the wind velocity is equal to zero 4 Required overall measurement accuracy The required overall measurem
33、ent accuracy shall be as follows: a) vehicle speed: 0,5 km/h or 1 %, whichever is greater; b) time: 50 ms or 0,1 %, whichever is greater; c) wheel torque: 3 Nm or 0,5 %, whichever is greater; d) wind speed: 0,3 m/s; e) wind direction: 3; f) atmospheric temperature: 1 K; g) atmospheric pressure: 0,3
34、kPa; h) vehicle mass: 10 kg; BS ISO 10521-1:20063i) tyre pressure: 5 kPa; j) product of aerodynamic coefficient and frontal projected area (SCd): 2 %; k) chassis-dynamometer roller speed: 0,5 km/h or 1 %, whichever is greater; l) chassis-dynamometer force: Category 1 chassis dynamometer: 6 N, or Cat
35、egory 2 chassis dynamometer: 10 N or 0,1 % of full scale, whichever is greater. NOTE The Category 2 chassis dynamometer usually has a greater load capacity, e.g. 130 kW or more. 5 Road-load measurement on road 5.1 Requirements for road test 5.1.1 Atmospheric conditions for road test 5.1.1.1 Wind The
36、 average wind speed over the test road shall not exceed 10 m/s, nor wind gusts exceed 14 m/s. Relevant wind correction shall be conducted according to the applicable type of anemometry specified in Table 1. In order to decide the applicability of each anemometry type, the average wind speed shall be
37、 determined by continuous wind speed measurement, using a recognized meteorological instrument, at a location and height above the road level alongside the test road where the most representative wind conditions will be experienced. NOTE Wind correction may be waived when the average wind speed is 3
38、 m/s or less. Table 1 Applicable anemometry depending on average wind speed and cross-wind component Wind speed in metres per second (m/s) Average wind speed Absolute wind speed v 5 Type of anemometry Cross-wind component (vc) v c 3 Cross-wind component (vc) 3 vc 5 Absolute wind speed 5 v 10 Station
39、ary anemometry Applicable Not applicable Not applicable Onboard anemometry Applicable Applicable Applicable NOTE The stationary anemometry is recommended when the absolute wind speed is less than 1 m/s. 5.1.1.2 Atmospheric temperature The atmospheric temperature shall be within the range of 274 to 3
40、08 K, inclusive. 5.1.2 Test road The road surface shall be flat, dry and hard, and its texture and composition shall be representative of current urban and highway road surfaces. The test-road longitudinal slope shall not exceed 1 %. The local BS ISO 10521-1:20064 inclination between any points 3 m
41、apart shall not deviate more than 0,5 % from this longitudinal slope. The maximum cross-sectional camber of the test road shall be 1,5 %. 5.2 Preparation for road test 5.2.1 Vehicle preparation 5.2.1.1 Vehicle condition The test vehicle shall be suitably run-in for the purpose of the subsequent test
42、. The tyres shall be suitably broken-in for the purpose of the subsequent test, while still having a tread depth of not less than 50 % of the initial tread depth. Unless any particular purpose is intended, the vehicle shall be in normal vehicle conditions, as specified by the manufacturer. That is,
43、tyre pressure (see 5.2.1.2), wheel alignment, vehicle height, lubricants in the drive-train and wheel-bearings, and brake adjustment to avoid unrepresentative parasitic drag. During the road test, the engine bonnet/hood and all windows shall be closed so that they will not influence the road-load me
44、asurement. Any covers of the air ventilation system, headlamps, etc., shall be closed, and the air-conditioning switched off. The vehicle mass shall be adjusted to meet the requirement of the intended subsequent test, including the mass of the driver and instruments. 5.2.1.2 Tyre-pressure adjustment
45、 If the difference between the ambient and soak temperature is more than 5 K, the tyre pressure shall be adjusted as follows. Soak the tyres for more than 4 h at 10 % above the target pressure. Just before testing, reduce the pressure down to the manufacturers recommended inflation pressure, adjuste
46、d for difference between the soaking-environment temperature and the ambient test temperature at a rate of 0,8 kPa per 1 K using the following formula: ()soak amb0,8tPTT= where Ptis the tyre pressure adjustment, in kilopascals (kPa); 0,8 is the pressure adjustment factor, in kilopascals per kelvin (
47、kPa/K); Tsoakis the tyre-soaking temperature, in kelvins (K); Tambis the test ambient temperature, in kelvins (K). 5.2.2 Installation of instruments Any instruments, especially for those installed outside the vehicle, shall be installed on the vehicle in such a manner as to minimize effects on the o
48、perating characteristics of the vehicle. BS ISO 10521-1:200655.2.3 Vehicle preconditioning Prior to the test, the vehicle shall be preconditioned appropriately, until stabilized and normal vehicle operating temperatures have been reached. It is recommended that the vehicle should be driven at the mo
49、st appropriate reference speed for a period of 30 min. During this preconditioning period, the vehicle speed shall not exceed the highest reference speed. 5.3 Measurement of total resistance by coastdown method The total resistance shall be determined by either the multi-segment method (5.3.1), the average deceleration method (5.3.2) or the direct regression method (5.3.3). 5.3.1 Multi-segment method 5.3.1.1 Selection of speed points for road-load curve determinatio
