The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 03, 2006
Filed:
Jun. 21, 2002
Rakesh K. Gupta, Morgantown, WV (US);
Sushant Agarwal, Morgantown, WV (US);
Rakesh K. Gupta, Morgantown, WV (US);
Sushant Agarwal, Morgantown, WV (US);
West Virginia University, Morgantown, WV (US);
Abstract
A method for making fluid elasticity measurements using an extensional viscometer () is disclosed, where stress is not directly measured but is inferred from an accurate measurement of the change in the rate of flow of a liquid during passage through a vertical capillary (). The flow rate changes when the liquid jet, also called the liquid filament, leaving a first capillary (), is stretched by the application of vacuum forces. Steady flow is established almost instantly by using a constant liquid head () above the capillary, and the flow rate is determined by timing the interval for liquid to drain between two marks () on the liquid reservoir surface. Extensional viscosity can be calculated as a ratio of the tensile stress and stretch rate of the liquid at different axial positions.