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STS-94, July 12, 1997, MET:11/07:00 (approximate). Looking more like an exploding star than a microgravity experiment on board the Shuttle, the Droplet Combustion Experiment (DCE) today used a fiber wire to support the fuel droplet during some burns. Scientists want to determine the effects that the fiber has on the burning of the droplet, and to compare results of this experiment and the FSDC (below). DCE also performed some burns using air and allowing the droplet to float free, making the test setup as identical as possible to single-droplet burns of FSDC except for the presence of the fiber. There will be a lot of interesting intercomparison data from these two experiments. The image at left shows the ignition of the vapor cloud around the droplet and the outline of the fiber (the two roughly horizontal lines on each side). An mpeg movie (1.3 MB) shows this burn.

STS-94, July 12, 1997, MET:10/19:13 (approximate). The Fiber-Supported Droplet Combustion (FSDC) continued today, using two droplets positioned on the fiber wire, instead of the usual one. Two droplets more closely simulates the environment in engines, which ignite many fuel droplets at once. The behavior of the burning was also unexpected - the droplets moved together after ignition, generating quite a bit of data for understanding the interaction of fuel droplets while they burn. An mpeg movie (1.3 MB) shows a time-lapse of this burn (3x speed). Because FSDC is backlit (the bright glow behind the drops), you cannot see the glow of the droplets while they burn - instead, you see them shrink! The small blobs left on the wire after the burn are the beads used to center the fuel droplet on the wire. FSDC was part of our featured story for July 12.

STS-94, July 12, 1997, MET:10/09:20 (approximate). TEMPUS (a German acronym roughly translated as "electromagnetic processing under weightlessness," continues a long run of processing samples. At left is an image of a gold sample as it's being heated by TEMPUS (yes, it's a furnace, too!). An mpeg time-lapse movie (450KB) shows the sample being positioned electromagnetically and starting to be heated to melting.

STS-94, July 12, 1997, MET:10/08:18 (approximate). The Structure of Flameballs at Low Lewis Numbers (SOFBALL) continues a series of stunningly successful burns. It was thought these extremely dim flameballs (1/20 the power of a kitchen match) could last up to 200 seconds - in fact, they can last for at least 500 seconds. This has ramifications in fuel-spray design in combustion engines, as well as fire safety in space. An mpeg-format time-lapse movie (904KB), shows the drift of these flameballs over nearly two minutes, compressed to approximately 10 seconds. The shuttle went into free-drift, without firing thrusters, for some SOFBALL burns. Today's featured story is on SOFBALL and FSDC (just below). SOFBALL is carried out in the Combustion Module-1 Facility.

STS-94, July 12, 1997, MET:10/08:13 (approximate). The Fiber-Supported Droplet Combustion (FSDC) experiment team is getting double for the money - more than twice as many burns have been completed as were originally scheduled for this flight. In fact, today the scientists were able to burn two droplets side by side, more closely mimicking behavior of burning fuel in an engine. At left, you see ignition of a single drop that subsequently burned while a fan blew through the chamber, giving the scientists data on burning with convection, but no buoyancy - an important distinction when you're trying to solve a problem by breaking it into parts. FSDC is carried out in the Combustion Module-1 Facility. A movie (1.1MB) shows this burn, and the seemingly premature extinction of the flame, explained in the featured story for today.

STS-94, July 12, 1997, MET:10/05:08 (approximate). Even after a hundred orbits of Earth - there's always something new to see. Here is a spectacular cloud circulation!

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Authors: John Horack, Linda Porter
Curator: Linda Porter
NASA Official: Gregory S. Wilson