Gas Surface Interactions Lab

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New paper in the International Journal of Heat and Mass Transfer!

May 30th, 2016

A new paper on the permeability of FiberForm has been published in the International Journal of Heat and Mass Transfer:

A series of experiments was performed to obtain permeability data on FiberForm®, a commercial carbon preform used for manufacturing thermal protection systems. A porous sample was placed in a quartz flow-tube heated by an isothermal furnace. The setup was instrumented to measure mass flow through and pressure drop across the sample. The intrinsic permeability and the Klinkenberg correction, which accounts for rarefied effects, were computed from the experimental data. The role of the gas temperature and pressure on the effective permeability is shown, and it is demonstrated that with proper data reduction, the intrinsic permeability is strictly a function of the micro-structure of the material. A function for the effective permeability of FiberForm, dependent on temperature, pressure, pore geometry, and type of gas is proposed. The intrinsic permeability was evaluated at K0=5.57×10-11 m2, with a Klinkenberg parameter of 8c/dp=2.51×105 m−1 and a reference porosity of ϕ=0.87.

Panerai, F., White, J. D., Cochell, T. J., Schroeder, O. M., Mansour, N. N., Wright, M. J., and Martin, A., “Experimental measurements of the permeability of fibrous carbon at high temperature,” International Journal of Heat and Mass Transfer, Vol. 101, October 2016, pp. 267–273.
DOI: 10.1016/j.ijheatmasstransfer.2016.05.016


New paper in CEAS Space Journal!

May 25th, 2016

A new paper has been published (online) in the CEAS Space Journal:

The spallation phenomenon was studied through numerical analysis using a coupled Lagrangian particle tracking code and a hypersonic aerothermodynamics com- putational fluid dynamics solver. The results show that car- bon emission from spalled particles results in a significant modification of the gas composition of the post-shock layer. Results from a test campaign at the NASA Langley HYM- ETS facility are presented. Using an automated image pro- cessing of short exposure images, two-dimensional velocity vectors of the spalled particles were calculated. In a 30-s test at 100 W/cm2 of cold-wall heat flux, more than 722 particles were detected, with an average velocity of 110 m/s.

Martin, A., Bailey, S. C. C., Panerai, F., Davuluri, R. S. C., Vazsonyi, A. R., Zhang, H., Lippay, Z. S., Mansour, N. N., Inman, J. A., Bathel, B. F., Splinter, S. C., and Danehy, P. M., “Numerical and experimental analysis of spallation phenomena,” CEAS Space Journal, Vol. 8, No. 3, September 2016.
DOI: 10.1007/s12567-016-0118-4