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Temperature gradients in large cold-seal pressure vessels

Published online by Cambridge University Press:  05 July 2018

J. A. Dalton
Affiliation:
Department of Earth Sciences, University of Sheffield, Dainton Building, Sheffield S3 7HF, UK
F. G. F. Gibb
Affiliation:
Department of Earth Sciences, University of Sheffield, Dainton Building, Sheffield S3 7HF, UK

Abstract

Radial and longitudinal temperature gradients within cold-seal pressure vessels can contribute significantly to the total temperature unccrtainty in any one experiment and it is important to calibrate such gradients before experiments are undertaken. We have measured temperature gradients in vertically mounted large cold-seal vessels at 1 atm and 1 kbar and in the temperature range 500–800°C Radial gradients were measured with the vessel at various positions within the furnace by recording the temperature difference between a thermocouple in the internal bore of the vessel and one in a well in the top of the vessel. We find that when the vessel is at a certain position in the furnace, the temperatures read by these two thermocouples are equivalent to within 1°C. The contribution of radial gradients to temperature uncertainty can be thus be substantially minimized if experiments are undertaken with the vessel in this position. Longitudinal gradients of 2.8°C/cm at 500°C and 3°C/cm at 800°C were recorded at 1 kbar. These profiles are significantly steeper than those recorded at 1 atm. Not to calibrate temperature gradients at the experimental conditions or failure to calibrate vessels at all could lead to large temperature uncertainties.

Type
Experimental
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1996

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Footnotes

*

Present address: Department of Geosciences, University of Texas at Dallas, P.O. Box 830688, Richardson, TX 75083-0688, USA.

References

Boettcher, A.L. and Kerrick, D.M. (1971) Temperature calibration of cold-seal pressure vessels. In: Research Techniques for High Pressure and High temperature (Ulmer, G.C., ed.) Springer-Verlag, New York, 174–81.Google Scholar
Charles, R.W. and Vidale, R. (1982) Temperature calibration of a new rapid quench vessel. Amer. Mineral., 67, 175–9.Google Scholar
Kerrick, D.M. (1987) Cold-seal systems. In: Hydrothermal Experimental Techniques (G.C. Ulmer and H.L. Barnes, eds.) Wiley, New York, 293324.Google Scholar
Rudert, V., I-M., Chou and Eugster, H.P. (1976) Temperature gradients in rapid-quench cold-seal pressure vessels. Amer. Minerals 61, 1012–5.Google Scholar