1、SURFACE VEHICLERECOMMENDED PRACTICEJ2867 AUG2014Issued 2014-08Laboratory Testing of Light Duty Vehicle Electric Cooling Fan Assemblies for Airflow PerformanceRATIONALEThis Recommended Practice is intended to describe a Standard method for measuring the performance characteristics of electric cooling
2、 fans (ECF), also known as “electric motor fans“ or “electric motor driven fans”. Today, there is a wide range of conditions under which OEMs request and/or ECF Suppliers measure and report performance. This current condition results in unnecessary variation in the data and its interpretation, makin
3、g it difficult to use the data for vehicleperformance prediction and even to accurately compare the performance of fans from different suppliers or even from the same supplier. The major ECF suppliers support the concept of having an Industry Standard for Performance Measurement.1. SCOPEThis SAE Rec
4、ommended Practice is intended for use in testing and evaluating the performance of Light Duty automotive electric engine cooling fans. These Electric Cooling Fan (ECF) Assemblies are purchased by Light Duty Truck and Passenger Car OEMs from suppliers. They are purchased as complete assemblies, consi
5、sting of the fan(s), motor(s), and shroud (see Figure 1); this Recommended Practice will only consider such complete assemblies. Some purchased assemblies using brush-type motors may also include control devices such as power resistors or pulse width modulation (PWM) electronics for speed control. I
6、n the case of brushless motor technology, the controller is an integral part of the motor where it also performs the commutation process electronically. The performance measurement would include fan output in terms of airflow and pressure, and fan input electric power in terms of voltage and current
7、. This information could then be used to calculate the efficiency of the assembly, including aerodynamic efficiency of the fan and shroud and electrical efficiency of the motor. The electric power consumption could be used to estimate vehicle energy as it relates to electrical charging system sizing
8、 and fuel economy.The test conditions in the procedure generally will not always match those of the installation for which cooling, electric energy consumption and fuel consumption information is desired. The performance of a given fan depends on the installation details of the application, includin
9、g the effects of system resistance and geometry of the grille, heat exchangers and underhood geometry of the engine and other underhood components. These details should be duplicated in the test setup, to the greatest extent possible, if accurate performance measurement is expected. Vehicle level ai
10、rflow performance will also be affected by the bumper profile and any other shape that would influence how the airflow enters the grille. _SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this re
11、port is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized,
12、or cancelled. SAE invites your written comments and suggestions.Copyright 2014 SAE InternationalAll rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise,
13、 without the prior written permission of SAE.TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada)Tel: +1 724-776-4970 (outside USA)Fax: 724-776-0790Email: CustomerServicesae.orgSAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedbackon this Technical Report, pleas
14、e visithttp:/www.sae.org/technical/standards/J2867_201408SAE INTERNATIONAL J2867 Issued AUG2014 Page 2 of 10FIGURE 1 - SINGLE LIGHT DUTY ELECTRIC COOLING FAN ASSEMBLY USING A BRUSHLESS MOTORIncludes Fan, Motor, Shroud, Stators, Electrical Connector and Pressure Relief Flaps for High Vehicle Speed Ap
15、plications1.1 PurposeThis document provides a recommended test procedure for measuring and comparing the performance of Electric Cooling Fan (ECF) Assemblies for Airflow Performance over a range of pressure and speeds in a test environment that includes the intended heat exchangers, providing a labo
16、ratory simulation of as-installed performance. The resulting performance data are intended for predicting the cooling performance and fuel consumption of engines using these fans, and in comparing one fan versus another. The primary purpose of this Recommended Practice is to provide a standard test
17、method such that airflow performance data can be accurately compared between ECF suppliers and OEMs, taking into consideration the different motor technologies and speed control methodology. The further purpose or rationale is that using different test setups and methods offers no competitive advant
18、age, adding cost but not value.Pressure Relief FlapsFan BladeMotorShroudElectrical ConnectorSAE INTERNATIONAL J2867 Issued AUG2014 Page 3 of 10In terms of usefulness of the data, there is one piece of data that differentiates ECF testing from airflow testing of fans using non-electric motor drive so
19、urces. The voltage and current are key inputs, just as the airflow and pressure are key outputs. If the motor is a brushless type, with PWM speed control, the OEM may have a great interest in comparing airflow versus pressure at various PWM inputs. But, from an ECF test standpoint, the PWM input (at
20、 a given system voltage) is just a control means to provide voltage and current to the motor.2. REFERENCES2.1 Applicable DocumentsThe following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publications shall apply.
21、2.1.1 SAE PublicationsAvailable from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.SAE J2873 Electric Cooling Fan Motor MountingSAE J1339 Test Method for Measuring Performance of Engine Cooli
22、ng Fans2.1.2 ANSI PublicationAvailable from American National Standards Institute, 25 West 43rd Street, New York, NY 10036-8002, Tel: 212-642-4900, www.ansi.org.ANSI/AMCA Standard 210-2007 ANSI/ASHRAE Standard 51-2007 American National Standard “Laboratory Methods of Testing Fans for Aerodynamic Per
23、formance Rating”3. TEST PROCEDURE3.1 Equipment and Facilities (see Figure 2)3.1.1 An Airflow Measurement Structure with minimum length, width, and height of 200% of the ECF Shroud assembly which includes a suitable plenum chamber. A calibrated flow measurement nozzle (one with experimentally determi
24、ned coefficient kn) should be coupled to this structure. The plenum chamber should preferably contain perforated “straightening” screens to dissipate jets of air and provide uniform air movement.3.1.2 An Auxiliary Blower and shutters (or other restrictive device) of appropriate shape and diameter to
25、 vary the plenum pressure.3.1.3 A method for mounting the ECF test component and the representative heat exchangers to the Airflow Measurement Structure. A plywood end-wall of the plenum is typically used for this purpose. Actual heat exchangers such as a Radiator, A/C Condenser, Charge-Air-Cooler a
26、nd Air/Oil Cooler are preferred in order to approximate the in-vehicle airflow restriction.3.1.4 A method of mounting rough shapes of plywood or other materials an appropriate distance behind the ECF to simulate the airflow restriction of underhood components, such as the engine.3.1.5 A calibrated v
27、ariable-voltage DC power supply capable of powering the ECF motor(s) through their entire design range. The power supply should have ability to provide accurate output voltage (V) and current (amps) such that these values can be recorded, and electrical power (W) calculated.SAE INTERNATIONAL J2867 I
28、ssued AUG2014 Page 4 of 10FIGURE 2 FAN PERFORMANCE TEST SETUP3.1.6 A method for measuring fan rotational speed (rpm). This can be a photoelectric device reading reflective tape applied to one fan blade, a magnetic pickup reading metal clips appropriately placed on the fan, or even a manual method us
29、ing a photo tachometer.3.1.7 A Pulse Generator to control the duty cycle input of a PWM Fan Controller (when applicable).3.1.8 Equipment necessary for measurement of air temperature, barometric pressure, differential pressure across the flow nozzle, and the pressure inside the plenum chamber.3.1.9 T
30、he ANSI/AMCA Standard referenced in Section 2.1.2 above provides guidance on preferred flowmeter construction, instrument accuracy, and alternative airflow calculations. Although it is primarily for fans with integral housings, its guidelines are applicable for non-ducted fan performance such as ECF
31、s.3.2 Test Conditions3.2.1 The ECF, including its motor(s) and shroud, should be mounted to the Airflow Measurement Structure in a manner that is representative of the vehicle installation. At a minimum, the correct heat exchangers (Radiator, A/C Condenser, CAC, Air/Oil Cooler) should be included to
32、 provide representative pressure restrictions. The exchangers will influence the air loading of the fan and therefore its speed for a given electrical power and pressure drop condition.3.2.2 The ECF and heat exchangers should be securely fastened to the Airflow Measurement Structure to prevent the c
33、omponents from being pulled into or blown out of the structure during testing.3.2.3 The ECF and heat exchangers should be sealed with duct tape (or similar methods) to prevent air from by-passing the units, and to maintain a serial flow path.3.2.4 Mount rough shapes of plywood or other materials an
34、appropriate distance behind and ahead of the ECF to simulate the airflow restriction of underhood components, such as the engine and vehicle grille. If possible, actual components should be used, up to and including the complete vehicle front-end.3.2.5 Air temperature range for the tests should be 1
35、0 to 50C.3.2.6 Specify exact test conditions used on the fan test report, plots, and/or tabulated data.Minimum dimensions for the Plenum End Wall shall be at least 200% of the Height, Width and Thickness dimensions for the ECF being testedSAE INTERNATIONAL J2867 Issued AUG2014 Page 5 of 103.3 Test P
36、rocedures3.3.1 Fan SpeedOperate the test fan over a range representative of the intended use. Select sufficient discrete speeds to establish performance for the speed range available per the vehicle speed control strategy. Choice of fan speed depends upon several factors, including the type of contr
37、ol system:3.3.1.1 Fan motors with fixed speed controls typically have three speeds (off, low, and high), achieved by using relays and a resistor (for single fans). 3.3.1.2 Dual fan units have the additional modes of series/parallel operation.3.3.1.3 Pulse Width Modulated (PWM) fan motors are capable
38、 of infinitely variable speeds. At a minimum, measurements at minimum power, 50%, 80%, and at full power are recommended (most PWM devices are calibrated to full power at less than 100% PWM - consult PWM manufacturer to determine appropriate signal input required).3.3.1.4 Many applications may requi
39、re measurements above and below normal vehicle voltage; i.e. for a 12-volt system, data may be taken at voltages from 9 to 16 volts.3.3.2 Test Setups3.3.2.1 Run 1: Flow Nozzle and End-wall Loss. As described in Section 3.1.3 above, mount an end-wall on the plenum with an opening sized to heat exchan
40、ger core width (Whx) and height (Hhx).3.3.2.2 Run 2: Flow Nozzle + Heat Exchangers. Install radiator to end-wall of Run 1 as described in Section 3.2 above, as well as all heat exchangers of interest (condenser, transmission oil cooler, charge air cooler, etc).3.3.2.3 Run 3: Flow Nozzle + Heat Excha
41、ngers + ECF Assembly (Fan Powered). Install ECF assembly to heat exchangers and set power level as desired (minimum power, various PWM levels, different voltages, etc). 3.3.2.4 Note that Run 3 may be conducted many times if different speeds and/or power levels are studied, but Run 1and Run 2 will ty
42、pically only need to be conducted once per heat exchanger setup.3.3.3 Data AcquisitionAt each discrete test speed and setup condition, vary the plenum pressure to various test points by using the auxiliary fan and/or shutters. The first point should be at a flow rate of Z, where Z is defined as the
43、maximum flow rate that the Air Measurement Structure can sustain without damage to the test components or facility. Reduce auxiliary fan speed and/or shutters opening to attain additional plenum pressure points. Usually a minimum of 5 discrete plenum pressure points should be sufficient to adequatel
44、y define fan performance. Plenum pressures should be both positive and negative. Typically, a minimum of 5 discrete plenum pressure points should be sufficient to define fan performance or the system restriction curve. At each plenum pressure point measure and record the following variables (see Tab
45、le 1 for preferred units):3.3.3.1 Fan speed, N3.3.3.2 Fan motor voltage, V3.3.3.3 Fan motor current, i3.3.3.4 Plenum pressure, Pp3.3.3.5 Nozzle differential pressure (Delta P), Pd3.3.3.6 Barometric pressure, B (may be acquired once per test if value does not change during test)3.3.3.7 Ambient air te
46、mperature, t (may be acquired once per test if value does not change during test)SAE INTERNATIONAL J2867 Issued AUG2014 Page 6 of 103.3.3.8 Relative humidity, RH (optional; collect if used in calculating air density)4. COMPUTATIONS AND RESULTS4.1 Definition of SymbolsTable 1 lists definitions and un
47、its of acquired data and subsequent calculated results.TABLE 1 - DEFINITION OF SYMBOLSSymbol DefinitionUnitsSIUnitsEnglishA Absolute temp. conversion factor 273 C 460 FB Barometric pressure kPa in HgC Air Density Correction Factor none noneD Air density kg/m3lbm/ft3Dsa Standard air density 1.20 kg/m
48、30.075 lbm/ft3dn Nozzle diameter meters inchesEs Fan static efficiency % %i Fan motor current (see note) amps ampsK Density conversion factorkf Flow conversion constant 2100 5.97kn Nozzle flow coefficient Function of nozzle geometryN Fan speed r/min r/minQAirflow3/min ft3/minPwr Fan motor power (act
49、ual) watts hpPwrth Theoretical staticair power watts hpPCRFM CRFM static pressure kPa in-H2OPd Nozzle pressure (Delta P) kPa in-H2OPp Plenum pressure kPa in-H2OPs Static pressure kPa in-H2ORH Relative humidity % %t Ambient temperature C FU Air power conversion factor 0.06 6356V Fan motor voltage (see note) volts voltsY Power conversion factor 1.0 0.00134 HP/wattZ Maximum facility airflow m3/min ft3/minSubscriptsc Corrected to stand
