Compressible Friction Coefficients in a Simulated Heat Pipe.
Abstract
Research was performed to verify previously obtained friction coefficients for compressible, laminar and turbulent flow in a simulated heat pipe for intermediate mass injection and suction rates. The research was divided into two main parts: an experimental study and numerical study. In the experimental study, a simulated heat pipe consisting of a long porous tube with air injected into one end to simulate the evaporator and extracted from the other end to simulate the condenser was investigated. Axial static pressure variations for various air supply mass flow rates were measured. It was found that the friction in the pipe decreased the amount of pressure recovery at the end of the pipe and that this decrease became even greater with increased supply mass flow rate. The pressure distributions obtained in the experimental study were used as input for a numerical simulation in the numerical portion of this research. A steady, one-dimensional computer code was developed to simulate the porous pipe system used in the experimental study in order to calculate Mach numbers, axial Reynolds numbers, and friction coefficients along the pipe. The results obtained for the friction coefficients in the porous pipe system studied did not correlate with the values predicted by Bowman's expressions. They exhibited the general trend expected for the friction coefficient - axial Reynolds number product with Mach number.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1987
- Accession Number
- ADA188818
Entities
People
- Constance A. Holladay
Organizations
- Air Force Institute of Technology