1、 WORLDWIDE ENGINEERING STANDARDS Test Procedure GMW14782 Air-Side Characteristics of the A/C and Heater Module Copyright 2011 General Motors Company All Rights Reserved December 2011 Originating Department: North American Engineering Standards Page 1 of 5 1 Scope Note: Nothing in this standard super
2、cedes applicable laws and regulations. Note: In the event of conflict between the English and domestic language, the English language shall take precedence. 1.1 Purpose. All test sequences shall be used to evaluate the air conditioning (A/C) and heater module itself, and shall, therefore, be perform
3、ed outside the vehicle. 1.1.1 Module Characteristic Curves. The air flow shall be determined as a function of the air-side resistance of the module for each of the six air settings: Bi-level (heater and ventilation), cold; Ventilation, cold; Heater cold; Heater warm; Defrost, warm; and Defog (heater
4、 and defrost), warm. The characteristic curves thus obtained are necessary on the one hand for evaluating the air-side capacity of the module; on the other hand, they set the preconditions for evaluating the flow quality of the air ducts in the vehicle. 1.1.2 Air Flow of “Bare Modules“ at a Specifie
5、d Air Resistance. The air capacity of the module as a function of the terminal voltage shall be examined for all the air settings of paragraph 1.1.1. To simulate as closely as possible the situation in the vehicle, resistance shall be applied upstream or downstream of the module, depending on the ai
6、r ducts being tested. See the appropriate Vehicle Technical Specification (VTS), Subsystem Technical Specification (SSTS), drawing, or equivalent. 1.2 Foreword. Not applicable. 1.3 Applicability. All A/C and heater modules. 2 References Note: Only the latest approved standards are applicable unless
7、otherwise specified. 2.1 External Standards/Specifications. None 2.2 GM Standards/Specifications. GMW3070 2.3 Additional References. Subsystem Technical Specification (SSTS) Vehicle Technical Specification (VTS) 3 Resources 3.1 Facilities. See details of test assembly and procedure for the specific
8、system at the test location. 3.2 Equipment. See details of test assembly and procedure for the specific system at the test location. 3.3 Test Vehicle/Test Piece. A/C or heater module. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduct
9、ion or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14782 Copyright 2011 General Motors Company All Rights Reserved December 2011 Page 2 of 5 3.4 Test Time. Not applicable. 3.5 Test Required Information. Not applicable. 3.6 Personnel/Skills. Not applicable.
10、 4 Procedure 4.1 Preparation. 4.1.1 Test Assembly. The test assembly must allow the air-side resistance outside the module to be varied. This can be achieved on the delivery or suction side of the blower, e.g., by means of a slider. 4.1.1.1 The air-side resistance of the module shall not be influenc
11、ed by the test assembly, i.e.: The free space in front of the blower intake must permit air to be sucked in “from infinity“, i.e., there shall be areas in which the air speed is practically zero. The air must be able to flow unhindered out of the module vents (“into infinity“). The air ducts shall n
12、ot be modified in any way by add-on parts (e.g., blower speed recorder). 4.1.1.2 The moment of inertia and the balance of the impeller may only be slightly changed by the blower speed recorder. 4.1.1.3 The blower voltage shall be measured directly at the motor terminals. 4.1.1.4 The module shall be
13、mounted in vehicle installation position. 4.1.1.5 The recirculating air flap shall be hermetically sealed. 4.1.1.6 The condensation drain shall be half closed. 4.1.1.7 The glove box cooler shall be closed. 4.1.1.8 In the event of unwanted air leakage (see paragraph 4.2.1), the module vents in questi
14、on shall be sealed. 4.1.2 With the blowers switched off, all instruments shall be calibrated to zero (“0“). During this process, all pressure gauges to be used in the test shall be compared. 4.1.3 For further information, see details of test assembly and procedure for the specific system. 4.2 Condit
15、ions. 4.2.1 Environmental Conditions. During the development phase of a module, it must be ensured that closed flaps do not leak. For further information, see details of test assembly and procedure for specific system. 4.2.2 Test Conditions. Deviations from the requirements of this standard shall ha
16、ve been agreed upon. Such requirements shall be specified on component drawings, test certificates, reports, etc. 4.3 Instructions. 4.3.1 The ambient temperature, relative humidity, and ambient pressure shall be recorded for each test sequence. Furthermore, the stability of these variables shall be
17、monitored during the test. 4.3.2 If modules with desired air leakage are tested, one measurement shall be taken with and one without leakage (e.g., floor with and without defrost bleed). 4.3.3 Module Characteristic Curves. At a fixed blower voltage of UG = 12 V (measurements at other voltages are pe
18、rmitted, if necessary), the blower current IG, blower speed nG, air flow VL, delivery pressure pF, corrected delivery pressure pFkorr and resistance RL shall be recorded. The air-side resistance is calculated by: RL = (PF korr)/(VL2) where pF korr is the delivery pressure corrected to normal conditi
19、ons. The following shall apply: pF korr = (pN )/(pBaro) pF Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14782 Copyright 2011 General M
20、otors Company All Rights Reserved December 2011 Page 3 of 5 Where: pN = Density at normal conditions pBaro = Measured density PF = Measured delivery pressure A test sequence for one air setting consists of ten single measurements in the range: 0 RL 100 10-3 Pas/L2 It shall be ensured that at least t
21、wo measurements are taken in the environment of the specified resistance. The free-blowing value for R = 0 shall be recorded. 4.3.4 Air Flow of “Bare Modules“ at a Specified Air Resistance. The resistance specified for each air duct shall be applied either upstream or downstream. The blower current
22、IG, blower speed nG and air flow VL shall be measured versus voltage in the range: 6 V UG 12 V, in 2 V steps. 4.3.4.1 Partial Recirculation and Ram Air Compensation. It shall be possible to adjust any mixture ratio between Recirculation and outside Air, independent from Blower speed, between 100% (f
23、ull Recirculation Air) and 0% (full outside Air). The ratio should be set in steps equal or less than 5%, taking into account the resolution of the actuators and the mechanical play of the flap(s). Note: Air bypass in partial Recirculation is not allowed. Partial Recirculation has to remain function
24、al at blower voltage UG = 3 V without bypass air from outside air (OSA) (see Figure 1, 20% OSA, 80% recirculation) to the cabin until pressure difference (see the SSTS for this value) between OSA air intake (measured in the Heating Ventilation Air Conditioning (HVAC) module/front of dash interface)
25、and pressure/resistance (P/R) air intake (measured on the compartment side of the P/R module inlet). Figure 1: Test Setup for Partial Recirculation Evaluation 4.3.4.2 Ram Air Compensating. An optional quote shall be provided to implement a second independent valve to restrict outside air with increa
26、sing vehicle speed. Module shall be capable of providing ram air compensation feature, if required. a ir d ir e c t io n in d ic a t o r sD e f r o s tV e n tF l o o rH e a t e rB l o w e r U ni t( a t l o w e s t b l o w e r l e ve l )O SAEvaporatorP O S AP P / RC ha m be r 1 C ha m be r 2recirc fl
27、ap OSA flap Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14782 Copyright 2011 General Motors Company All Rights Reserved December 2011
28、 Page 4 of 5 4.3.4.3 Air Inlet Protection. Design must accommodate the addition of a course screen mesh on the recirculation air inlet. If recirculation air inlet is placed near the glove box, such that papers can be sucked into the inlet, then a coarse screen mesh may be necessary and the glove box
29、 ingestion test must be passed per VTS section 3.2.1.3.7.2.4. Test according to GMW3070. 4.3.5 For further information, see details of test assembly and procedure for specific system. 5 Data 5.1 Calculations. Not applicable. 5.2 Interpretation of Results. Not applicable. 5.3 Test Documentation. 5.3.
30、1 Targets. See appropriate drawing, VTS, etc. 5.3.2 Evaluation. The values shall be determined during the test (see paragraphs 4.3.3 and 4.3.4). The evaluation shall be performed as specified in the led out test report. 5.3.3 Presentation. For the documentation of the test, the test report with the
31、associated diagrams shall be applied. 6 Safety This standard may involve hazardous materials, operations, and equipment. This standard does not propose to address all the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety an
32、d health practices and determine the applicability of regulatory limitations prior to use. 7 Notes 7.1 Glossary. Not applicable. 7.2 Acronyms, Abbreviations, and Symbols. A/C Air Conditioning HVAC Heating Ventilation Air Conditioning IG Blower Current nG Blower Speed OSA Outside Air pF Delivery Pres
33、sure pFkorr Corrected Delivery Pressure P/R Pressure/Resistance RL Resistance SSTS Subsystem Technical Specification UG Blower Voltage VL Air Flow VTS Vehicle Technical Specification 8 Coding System This standard shall be referenced in other documents, drawings, etc., as follows: Test to GMW14782 Co
34、pyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14782 Copyright 2011 General Motors Company All Rights Reserved December 2011 Page 5 of 5 9
35、 Release and Revisions This standard was originated in November 2005. It was first approved by HVAC Module Global Sub-System Leadership Team in February 2006. It was first published in March 2006. Issue Publication Date Description (Organization) 1 MAR 2006 Initial publication. 2 DEC 2011 Update for 5 Year Refresh. (HVAC Module GSSLT) Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
