Basic Mechanisms of Noncondensable Gas Cryotrapping

Item

Title
Basic Mechanisms of Noncondensable Gas Cryotrapping
Date
1963
Index Abstract
Not Available
Photo Quality
Incomplete
Report Number
AEDC TDR 63-147
Corporate Author
General Technology Corporation
Extent
58
Identifier
AD0410735
Distribution Classification
1
Contract
AF 40(600)-941
DoD Project
6950
DoD Task
695001
DTIC Record Exists
No
Distribution Change Authority Correspondence
None
Abstract
Systematic measurements are reported on the rate at which argon and nitrogen are trapped by water as it condenses under vacuum onto a 77 K surface. For condensation rates between 10 to the 15th power and 10 to the 18th power molecules per sq. cm -sec. and noncondensable partial pressures between 0.000001 and 0.1 torr, trapping rates are proportional to condensation rate and a concen tration of adsorbed gas. The latter are described by Langmuir isotherms with characteristic pres sures for saturation of 0.0025 torr and 0.0035 torr for nitrogen and argon respectively. Inde pendent adsorption measurements show that quantity of gas adsorbed is proportional to mass of con densate (approximately 600 sq. meters per gram) and depends on pressure identically with the trap ping. Apparent trapping due to adsorption on surface area generated during condensation is only about 7% of actual trapping. All the results are consistent with a mixed phase for the con densate of which approximately 10% is the 12A gas hydrate.
Report Availability
Full text available by request
Date Issued
1963-07
Publisher
Arnold Air Force Station, TN : Arnold Engineering Development Center, Air Force Systems Command, United States Air Force
Provenance
IIT
Type
report
Format
58 pages ; 28 cm.