Joseph Shakal, 後藤新一 （機械研）

INTRODUCTION

A piezo disk was used to generate a cloud of n-decane fuel drops (or particles), which were mixed with air, then carried into a combustion chamber and ignited by a platinum wire. Measurements at normal gravity were compared to microgravity results obtained at the Japan Microgravity Center (JAMIC). The chamber, which was cylindrical (90mm diameter x 150mm high) was kept at 1 Atm pressure and the initial temperature was 20C. Measurements showed the arithmetic mean droplet size was 1.5 microns and the Sauter mean diameter (SMD) was 1.9 microns. The particle density was measured by a light extinction technique[1], and the horizontal flame front speed was measured using a nac Memricam-ci high-speed digital camera. We recorded the flame growth at 500 FPS, unshuttered, and triggered by the igniter signal. This camera has a 1/2 inch CCD chip with 572x434 pixels, and a gain of 12 was used.

Main Experimental Equipment