BS EN 16211:2015
$167.15
Ventilation for buildings. Measurement of air flows on site. Methods
| Published By | Publication Date | Number of Pages |
| BSI | 2015 | 44 |
This European Standard specifies simplified methods for the measurement of air flows on site. It provides a description of the air flow methods and how measurements are performed within the margins of stipulated method uncertainties.
One measurement method is to take point velocity measurements across a cross-section of a duct to obtain the air flow. This simplified method is an alternative to the method described in ISO 3966 and EN 12599 . This European Standard requests certain measurement conditions (length of straight duct and uniform velocity profile) to be met to achieve the stipulated measurement uncertainties for the simplified method.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 4 | Contents Page |
| 6 | Foreword |
| 7 | 1 Scope 2 Normative references 3 Terms, definitions and symbols 3.1 Terms and definitions 3.2 Symbols |
| 9 | 4 Principles and parameters of influence 4.1 Hydraulic diameter 4.2 Flow disturbances 4.3 Air density, ρ 4.4 Dynamic pressure, pd |
| 10 | 4.5 Corrections for air density, ρ 5 Sources of errors 5.1 General |
| 11 | 5.2 Systematic errors Figure 1 — Explanation of systematic error |
| 12 | 5.3 Random errors 6 Measurement uncertainty 6.1 Overall measurement uncertainty |
| 13 | 6.2 Standard instrument uncertainty, u1 6.3 Standard method uncertainty, u2 6.4 Standard reading uncertainty, u3 6.5 Expanded measurement uncertainty, Um |
| 14 | 7 Measurement requirements 7.1 Method requirements and corrections 7.2 Measurements using a manometer Table 1 — Resolution for the ranges of manometers |
| 15 | 7.3 Measurements using an anemometer 7.4 Measurements using Pitot static tube 7.5 Measuring temperature and barometric pressure 7.6 Mean value calculation of measurement signal 8 Methods for measurement of air flows in ducts – ID (In Duct) methods 8.1 Overview of recommended methods |
| 16 | Table 2 — Methods of measurement of airflows in duct 8.2 Point velocity measurements using a Pitot static tube (method ID 1) or an anemometer (method ID 2) 8.2.1 Method description |
| 17 | Figure 2 — Measurements with Pitot static tubes 8.2.2 Preparations to be made at the site of measurement 8.2.2.1 Equipment |
| 18 | 8.2.2.2 Necessary straight sections before and after the plane of measurement Table 3 — Necessary straight sections before and after the plane of measurement 8.2.2.3 Preparation procedure and selection of measuring planes |
| 19 | Table 4 — Measurement points for circular ducts Table 5 — Measurement points for rectangular ducts related to the longer dimension: L2 Table 6 — Measurements points for rectangular ducts related to the longer dimension — Values recalculated in accordance with L2 |
| 20 | Table 7 — Measurements points for rectangular ducts on the height, L1 Figure 3 — Cases A and B — Cross-section of a horizontal duct — A bent upstream is in a horizontal or vertical plane 8.2.3 Measurement procedure |
| 21 | 8.2.4 Corrections of measured values and calculation of air flow Figure 4 — Correction factor k1 for density |
| 22 | Table 8 — Correction for duct shape k2 for circular ducts Table 9 — Correction for duct shape k2 for rectangular ducts 8.2.5 Standard method uncertainty 8.3 Fixed devices for flow measurement – Method ID 3 8.3.1 Method description 8.3.2 Preparations of measurements — Equipment |
| 23 | 8.3.3 Measurement procedure 8.3.4 Correction of measured values 8.3.5 Standard method uncertainty 8.4 Tracer gas measurement – Method ID 4 8.4.1 Method description |
| 24 | 8.4.2 Equipment Figure 5 — Tracer gas measurement equipment |
| 25 | Figure 6 — Nozzle device for injecting tracer gas 8.4.3 Calculation of air flow Table 10 — Example of density of N2O 8.4.4 Standard measurement uncertainty |
| 26 | 8.4.5 Conditions for homogeneous mixing of tracer gas Table 11 — Mixing length (L) required for standard method uncertainty to fall below 5 % and 10 % |
| 27 | 9 Methods for measurement of air flows in Supply ATDs (air terminal devices) – ST (Supply (Air) Terminal (Devices)) methods 9.1 Overview of recommended methods Table 12 — Methods of measurement of supply airflows at ATD 9.2 Measurement of reference pressure – Method ST 1 9.2.1 Introduction |
| 28 | Figure 7 — Example: Effects of disturbance from a 90 bend for terminal with pressure nozzles in the intake 9.2.2 Equipment 9.2.3 Correction of measured values |
| 29 | 9.2.4 Standard method uncertainty 9.3 Measurement with tight bag – Method ST 2 9.3.1 Method description Figure 8 — The principles of the measurement bag method 9.3.2 Limitations 9.3.3 Equipment |
| 30 | 9.3.4 Preparation 9.3.5 Measurement 9.3.6 Correction of measured values 9.3.7 Standard method uncertainty 9.4 Measurements with flow hood – Method ST 3 9.4.1 Introduction |
| 31 | 9.4.2 Equipment |
| 32 | Figure 9 — Example of measurement using method ST 31 Figure 10 — Flow hood with auxiliary fan (ST 32) 9.4.3 Measurement |
| 33 | 9.4.4 Correction of measured values 9.4.5 Standard method uncertainty |
| 34 | 10 Methods for Exhaust ATDs (air terminal devices) – ET (Exhaust (Air) Terminal (Devices)) methods 10.1 Overview of recommended methods Table 13 — Methods of measurement of exhaust airflows at ATD 10.2 Measurement of reference pressure at exhaust ATD – Method ET 1 10.2.1 Method description |
| 35 | Figure 11 — Example of measurement using Method ET 1 10.2.2 Limitations 10.2.3 Equipment 10.2.4 Correction of measured values |
| 36 | 10.2.5 Standard method uncertainty 10.3 Measurement using a flow hood – Method ET 2 10.3.1 Introduction 10.3.2 Equipment |
| 37 | Figure 12 — Example of measurement using method ET 21 Figure 13 — Example of measurement using method ET 22 10.3.3 Measurement |
| 38 | 10.3.4 Correction of measured values 10.3.5 Standard method uncertainty |
| 39 | Annex A (informative) Uncertainties A.1 Examples of calculations |
| 40 | A.2 Compound uncertainties A.3 Example of applications |
| 41 | Bibliography |
