API 2558 : 1993

Table of Contents

1.0 Introduction
2.0 Background
2.1 Evaporative loss equation
2.2 Air flow around tanks
2.3 Wind speeds in the atmosphere
3.0 Experimental program
3.1 Similarity criteria
3.2 Model construction
3.3 Wind tunnel and test setup
3.4 Wind direction
3.5 Wind speed
3.6 Roof pressures
3.7 Quality control
4.0 Results
4.1 General
4.2 Wind speed
4.3 Wind direction
4.4 Roof top pressures
5.0 Revised method for calculating evaporation from
     roof fittings
5.1 General
5.2 Complex method
5.3 Simple method
5.4 Discussion
6.0 Conclusion and recommendations
7.0 References
Appendices
A Instrumentation and facilities
B Experimental methods
C Table of pressure coefficients
D Pressure coefficient plots at measurement locations
E Pressure coefficient contours by wind direction
F Wind direction photographs
G Table of non-dimensional and equivalent wind
   velocities
H Wind rose of non-dimensional and equivalent wind
   velocities
I Non-dimensional mean velocity contours
Figures
1a Site plan - 200 ft tank
 b Elevation - 200 ft tank
2a Site plan - 100 ft tank
 b Elevation - 100 ft tank
3a Site plan - 48 ft tank
 b Elevation - 48 ft tank
4 Velocity and turbulent approach profiles
5a Wind speed, wind direction and roof pressure
     measurement locations - 200 ft tank
 b Wind speed, wind direction and roof pressure
     measurement locations - 100 ft tank
 c Wind speed, wind direction and roof pressure
     measurement locations - 48 ft tank
6a Non-dimensional mean velocity centerline profiles -
     200 ft tank
 b Non-dimensional mean velocity centerline profiles -
     100 ft tank
 c Non-dimensional mean velocity centerline profiles -
     48 ft tank
7a Average non-dimensional mean velocity contours -
     200 ft tank
 b Average non-dimensional mean velocity contours -
     100 ft tank
 c Average non-dimensional mean velocity contours -
     48 ft tank
8a Roof top wind directions relative to approach flow
     - 200 ft tank
 b Roof top wind directions relative to approach flow
     - 100 ft tank
 c Roof top wind directions relative to approach flow
     - 48 ft tank
9a Centerline pressure coefficient profiles - 200 ft
     tank
 b Centerline pressure coefficient profiles - 100 ft
     tank
 c Centerline pressure coefficient profiles - 48 ft
     tank
10a Average pressure coefficient contours - 200 ft tank
  b Average pressure coefficient contours - 100 ft tank
  c Average pressure coefficient contours - 48 ft tank
11a Average non-dimensional mean velocity zones - 200
     ft tank
  b Average non-dimensional mean velocity zones - 100
     ft tank
  c Average non-dimensional mean velocity zones - 48 ft
     tank
12a Average non-dimensional mean velocity centerline
     profiles - 200 ft tank
  b Average non-dimensional mean velocity centerline
     profiles - 100 ft tank
  c Average non-dimensional mean velocity centerline
     profiles - 48 ft tank
Tables
1 List of external roof fittings
2 Flow visualization test plan
3 Velocity measurement test plan
4 Pressure measurement test plan
5 Summary of wind directions on tank roof
6a Evaporative loss example calculation - complex
    method roof manway
 b Evaporative loss example calculation - complex
    method slotted guide pole
7 Evaporative loss example calculation - simple method

Abstract

Gives outcome of a wind tunnel study to determine the local wind velocities, wind directions, and roof pressures on external floating roof tanks.

General Product Information

Published
Document Type	Standard
Status	Current
Publisher	American Petroleum Institute
Pages
ISBN