Thin Film Measurement Assessment of the VPCAR Water Recovery System in Partial and Microgravity NASA Glenn Research Center

Format:

Conference/Event

Author/Creator:

Hall, Nancy Rabel, author.

Conference Name:

International Conference On Environmental Systems (2007-07-09 : Chicago, Illinois, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2007

Summary:

The Vapor Phase Catalytic Ammonia Removal (VPCAR) system is being developed to recycle water for future NASA Exploration Missions [1,2,3,4,5]. Reduced gravity testing of the VPCAR System has been initiated to identify any potential problems with microgravity operation. Two microgravity testing campaigns have been conducted on NASA's C-9B Reduced Gravity Aircraft. These tests focused on the fluid dynamics of the unit's Wiped-Film Rotating Disk (WFRD) evaporator.The experiments used a simplified system to study the process of forming a thin film on a rotating disk. The configuration simulates the application of feed in the VPCAR's WFRD evaporator. The first round of aircraft testing, which was completed in early 2006, indicated that a problem with microgravity operation of the WFRD existed. It was shown that in reduced gravity the VPCAR wiper did not produce a uniform thin film [6]. The film was thicker near the axis of rotation where centrifugal forces are small. A thickening of this film could have a negative effect on the heat transfer coefficient of the evaporator and could result in higher than expected specific power consumption during microgravity operation.In the second round of microgravity tests a potential solution to this problem was tested. This test demonstrated that mounting the feed wiper slightly higher than the axis of rotation of the WFRD disk produced a uniform thin film. This paper presents the results of this reduced gravity testing

Notes:

Vendor supplied data

Publisher Number:

2007-01-3039

Access Restriction:

Restricted for use by site license