GB/T 30206.2-2026Aerospace fluid systems vocabulary - Part 2: General terms and definitions relating to flow (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents".

Drafting.

This document is Part 2 of GB/T 30206 "Aerospace Fluid Systems Vocabulary". GB/T 30206 has already published the following parts.

---Part 1: General terms and definitions related to pressure;

---Part 2: General Terms and Definitions Related to Traffic;

---Part 3: General terms and definitions related to temperature;

---Part 4: General terms and definitions related to control/actuation systems.

This document replaces GB/T 30206.2-2013 "Aerospace Fluid Systems Vocabulary Part 2: General Terms and Definitions Related to Flow".

Compared with GB/T 30206.2-2013, the main technical changes in the "Meaning" are as follows, apart from structural adjustments and editorial modifications.

---Added the term and definition of "Reynolds number" (see 3.10);

--- Twelve terms and definitions, including "cavitation," have been revised (see sections 3.1, 3.2, 3.3.2, 3.4, 3.6, 3.7.1~3.7.4, 3.8, 3.9, and 3.11).

(Versions 2.1, 2.2, 2.14, 2.4, 2.6, 2.8.1, 2.8.2, 2.9, 2.13, and 2.10~2.12 from the 2013 edition)

---The term and definition of "exudation" have been removed (see 2.15 of the 2013 edition).

This document is equivalent to ISO 8625-2:2018 "Aerospace fluid systems - Vocabulary - Part 2: General terms related to flow rate".

and definition.

The following minimal editorial changes have been made to this document.

---To align with existing standards, the standard name has been changed to "Aerospace Fluid Systems Glossary Part 2: General Terms Related to Flow".

"Terms and Definitions".

Please note that some content in this document may involve patents. The issuing organization of this document assumes no responsibility for identifying patents.

This document was proposed and is under the jurisdiction of the National Aircraft Standardization Technical Committee (SAC/TC435).

Introduction

GB/T 30206 specifies the general terminology and definitions applicable to pressure, flow rate, temperature, and control/actuation systems in aerospace fluid systems.

The character (yì) is composed of four parts.

---Part 1: General Terms and Definitions Related to Pressure. The aim is to standardize pressure-related terms and definitions in the field of aerospace fluid systems.

General terms and definitions.

---Part 2: General Terms and Definitions Related to Flow. The aim is to standardize the understanding of flow-related terms in the field of aerospace fluid systems.

General terms and definitions.

---Part 3: General Terminology and Definitions Related to Temperature. The aim is to standardize temperature-related terms and definitions in the field of aerospace fluid systems.

General terms and definitions.

---Part 4: General Terminology and Definitions Related to Control/Actuation Systems. The aim is to unify the terminology and definitions used in the field of aerospace fluid systems related to control/actuation systems.

General terms and definitions related to braking/actuation systems.

Aerospace Fluid Systems Terminology Part 2: General Terms and Definitions Related to Traffic

1 Scope

This document defines the general terminology and definitions used in aerospace fluid systems related to flow rate.

2 Normative references

This document has no normative references.

3 Terms and Definitions

The following terms and definitions apply to this document.

Cavitation

Implosion is the phenomenon of gas or vapor cavitation forming and collapsing in a liquid. It occurs when the local pressure drops below the liquid's saturated vapor pressure.

When the pressure rises above the vapor pressure of the liquid, cavitation occurs.

Note 1.This may include gas that escapes from the solution in the liquid when the pressure decreases (soft cavitation).

Note 2.The cavitation tendency of a fluid is described by the cavitation number.

Note 3.If this occurs, the implosion or collapse of these cavities/bubbles will generate a powerful shock wave within the pump. If not remedied immediately, cavitation can cause serious damage.

Components and systems are damaged.