GB/T 45627-2025 Inspection specification for automobile climatic wind tunnel English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS 19.040
CCS T 36
National Standard of the People's Republic of China
GB/T 45627-2025
Technical specification for inspection of automobile environment wind tunnel laboratory
Issue date: 2025-04-25 Implementation date: 2026-11-01
Issued by the State Administration for Market Regulation
the National Standardization Administration of the People's Republic of China
Contents
Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Composition of automobile environmental wind tunnel laboratory
5 Inspection Rules
6 Test method
7 Inspection period
Annex A (Informative) Symbol
Bibliography
Technical specification for inspection of automobile environment wind tunnel laboratory
1 Scope
This document specifies the inspection regulations and inspection cycle of automobile environmental wind tunnel laboratory inspection, and describes the corresponding inspection methods.
This document is applicable to the inspection of automobile environmental wind tunnel laboratory, as well as the inspection of other similar test equipment. The inspection methods specified in this document are used for various environmental simulation systems: the indication values of temperature, humidity, wind speed, sunshine radiation, rain and snow and their uniformity, stability, conversion rate, and aerodynamic parameters, including the inspection of wind tunnel airflow deflection angle, boundary layer thickness, and axial static pressure gradient.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
JJG 518-2023 Verification regulation of pitot tube
JJF 1033-2023 Measurement standard assessment specification
3 Terms and definitions
The following terms and definitions are applicable to this document.
3.1 Process control
3.1.1
steady state
The characteristic parameters of the system are maintained constant system state
[GB/T 17212-1998, P1.2.0.05]
3.1.2
steady time
time required from the initial reaching of the set value to the reaching of the new steady state when the parameter transitions from a certain starting state to a new steady state
3.1.3
setting time
time interval required from the step change of the input signal to the time when the output variable remains within the specified tolerance band of the value of the input value multiplied by the static gain minus the first-order steady-state deviation of the output variable
[Source: GB/T 17212-1998, P1.2.1.03,P1.2.1.04, modified]
3.1.4
ramp rate
ratio of conversion amount to conversion time when a parameter is converted from one steady state to another
3.2 Position Definition
3.2.1
Rectangular Coordinate of Wind Tunnel Test Section
A coordinate system is established to define spatial positions within the wind tunnel test section. The origin is located at the midpoint of the intersection between the effective area of the nozzle and the test section floor. The X-axis extends from the origin perpendicular to the wind tunnel outlet.
Note: The coordinate system for vehicle environmental wind tunnel test sections is illustrated in Figure 1.
4 Components of Vehicle Environmental Wind Tunnel Test Facility
4.1 Overview
The vehicle environmental wind tunnel test facility primarily consists of:
Temperature, humidity, wind speed, and boundary layer simulation systems
Vehicle driving load simulation system
Solar radiation simulation system
Rain/snow simulation system
Hot ground simulation system
These systems collectively simulate natural environmental conditions under real-world vehicle testing scenarios.
4.2 Temperature, Humidity, Wind Speed, and Boundary Layer Simulation Systems
Temperature simulation system: Controls airflow temperature via heating/cooling equipment (e.g., heaters, refrigeration units, valves, pumps, pipelines, and closed-loop control).
Humidity simulation system: Manages airflow humidity through humidification (e.g., electric or steam humidifiers) and dehumidification (e.g., cooling or adsorption dehumidifiers), with closed-loop control.
Wind speed simulation system: Simulates airflow during vehicle movement using adjustable-speed fans, closed wind tunnels, flow straighteners (e.g., honeycomb grids), and control systems to meet uniformity and angle requirements.
Boundary layer simulation system: Removes boundary layer airflow along the ground using suction devices, adjustable fans, and pipelines to minimize impact on vehicle underside airflow.
4.3 Vehicle Driving Load Simulation System
Simulates vehicle inertia, resistance, and road gradients using:
Inertia simulation devices, Power absorption loaders,Rollers
4.4 Solar Radiation Simulation System
Replicates sunlight intensity during driving with:
Arrayed solar lamps, Dimmers, Height-adjustable mechanisms
4.5 Rain/Snow Simulation System
Simulates precipitation in the test section using:
Nozzles, Motion control mechanisms, Piping and control systems
4.6 Hot Ground Simulation System
Models pavement thermal effects with: Heated plates,Power regulators, Control systems
