IAS METHOD FOR 2D DATA ANALYSIS ON PC's

INTRODUCTION

Later chapters in this document describe how to run PC-based software to classify and view image records acquired from PMS 2D-C and 2D-P probes. The name we use for this package is TOUCH2D. It is a derivative of a package by the same name put together by Joanne Parrish (now Joanne George) and Andy Heymsfield at NCAR. Further processing of this image data can be done with the IAS programs ANALYZE and ANELAP. Their operation is also described in this bulletin. This second C-based software package produces output files containing size distributions and estimates of particle number and mass concentrations.

The purpose of the present bulletin is to describe the details of the processing performed by these programs and to provide instructions for running them. The categories into which particle shadow images are classified will be explained, and the techniques employed to estimate particle number and mass concentrations will be described.

The authors welcome questions and comments from users. We will attempt to update this bulletin as required to keep up with these continually-evolving software packages, and to further elaborate on those portions users find unclear. We hope you all can use these programs to pursue the scientific goals you have defined for yourselves.

We are especially indebted to Joanne (Parrish) George and Andy Heymsfield of NCAR for giving us their TOUCH2D package to use in our research. We also wish to thank Ed Holroyd (Bureau of Reclamation), Al Cooper (NCAR) and Mort Glass (AFGL) who supplied algorithms and/or codes from which we have borrowed for building our software packages.

Table of Contents

Introduction

Chapter 1 - Discussion of Probes

How do PMS OAP-2D Probes work?
Figure 1. Schematic diagram of 2D-C probe optical path
Figure 2. Hardcopy of two 2D-C image buggers produced by the VAX Program PIMAGE.

Chapter 2 - Particle Shadow Classification

Please note that due to the number of figures in this chapter, loading may take a few minutes longer.

Figure 3. Density versus diameter for lump graupel.
Figure 4. Standard TOUCH2D image display format.
Figure 5. Examples of "broken" particle shadowgraphs from a 2D-C probe.
Figure 6. Examples of 2D-C "streakers".
Figure 7. Examples of "hole" images from a 2D-C.
Figure 8. Examples of "tiny" shadowgraphs from a 2D-P.
Figure 9. Examples of "circular" images from a 2D-C.
Figure 10. Examples of "nearly circular" images from a 2D-P.
Figure 11. Examples of "regular" shadowgraphs from a 2D-C and a 2D-P.
Figure 12. Examples of "irregular" images from a 2D-C.
Figure 13. Examples of "linear" particle images from a 2D-P and a 2D-C.

Chapter 3 - PRELIM2D Program

Data File Preparation
PRELIM2D

Chapter 4 - TOUCH2D Program

Chapter 5 - ANALYZE and ANELAP

References

Appendix A - PRELIM2D Example Screens

'Initial PRELIM2D setup menu'
'User has made all selections' menu screens
'PRELIM2D file specification screen'
'Automated procedure in progress' screens

Appendix B - TOUCH2D Example Screens

'TOUCH2D initial display'
'TOUCH2D setup menu' screens
'Buffer habit breakdown and action menu'
'Select habit menu' screens
'Change diameter range'
'Images displayed' screens
'Select particle to change'
'Modify particle data' screens
'Viewing entire buffer' screen

Appendix C - ANALYZE Example Screens

Appendix D - Output files from ANALYZE/ANELAP

Example of concentration file
Example of mass file