PROPOSAL NUMBER 99-1 07.02-6233 (Chron: 990664)
PROJECT TITLE
ADVANCED SIMULATION OF OPTICAL FIBER DRAWING FROM ZBLAN PREFORM IN
MICROGRAVITY
TECHNICAL ABSTRACT (LIMIT 200 WORDS)
This SBIR Phase I project proposes to develop a high-performance computational tool for detailed simulation of thermal transport in optical fiber drawing processes. The initial experiments in the ZBLAN Microgravity Program indicate that unlike in the normal gravity conditions the fibers processed in microgravity did not show signs of crystallization. An explanation of the observed phenomena requires a clear understanding of thermal transport involving radiative heat transfer and two-phase flow with a curved free surface. In Phase I, an accurate and efficient radiation model will be developed to simulate radiative heat transfer in the gas enclosure as well as inside the fiberglass. The Navier-Stokes equations will be solved for both glass and external gas, which are coupled by the conjugate boundary conditions at the interface. The multizone adaptive grid generation (MAGG) technique will be used to discretize the physical domain due to its high quality characteristics for free-surface problems. The computational efficiency will be highly enhanced by implementing a parallel computing strategy with an efficient matrix solver. The Phase I will demonstrate the high accuracy and efficiency of the proposed thermal transport process model. In Phase II, the crystal formation model will be developed and coupled with thermal transport models.
POTENTIAL COMMERCIAL APPLICATIONS
The ZBLAN optical fibers may replace the existing silica optical fibers in the next century because they have broader spectrum and lower loss coefficient. The proposed simulation tool will significantly benefit the optical fiber industry that requires a detailed understanding of multimode and highly coupled transport phenomena and their interactions with thermal induced defects. The potential applications include the design, optimization, and control of optical fiber drawing process and many other manufacturing and materials processing systems.
NAME AND ADDRESS OF PRINCIPAL INVESTIGATOR (Name, Organization Name, Mail
Address,
City/State/Zip)
Dr. Jiwen Liu
Engineering Sciences, Inc.
1900 Golf Road, Suite D
Huntsville , AL 35802 - 4319
NAME AND ADDRESS OF OFFEROR (Firm Name, Mail Address, City/State/Zip)
Engineering Sciences, Inc.
1900 Golf Road, Suite D
Huntsville , AL 35802 - 4319