The Thermal Control Concept of the Mars Netlander Surface Module

This paper presents the development background and the present status of the Atmospheric Cloud Physics Laboratory (ACPL) thermal control capability. The ACPL, a Spacelab Payload, is currently in the initial flight hardware development phase for a first flight scheduled in June 1981. The ACPL is intended as a facility for conducting a wide variety of cloud microphysics experimentation under zero gravity conditions. The cloud chambers, which are key elements of the ACPL, have stringent thermal requirements. Thus the Expansion Chamber inner walls must be uniform to within ±0.1°C during both steady state and transient operation over a temperature range of +30 to −25°C. Design progression of the Expansion Chamber, from early inhouse NASA-MSFC concepts (including test results of a prototype chamber) to the thermal control concept currently under development at General Electric, is discussed.

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Heat and Mass Transfer in Loop Heat Pipes

Heat Transfer: Volume 2 ◽

10.1115/ht2003-47366 ◽

2003 ◽

Cited By ~ 20

Author(s):

Triem T. Hoang ◽

Jentung Ku

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

High Performance ◽

Heat Pipes ◽

Thermal Control ◽

Complete Understanding ◽

Loop Heat Pipes ◽

Transfer Processes ◽

Mass Transfer Processes ◽

Control Concept

Loop Heat Pipes (LHPs) have gained acceptance among spacecraft engineers in recent years as high performance heat transport devices for thermal control systems (TCS). However, the most common criticism from people who use LHPs is that their behavior is difficult to predict. Complex interaction of thermodynamics and fluid flow dynamics inside a LHP poses a challenge for the analytical modeling of its performance. The need for a complete understanding of mechanisms involving the heat and mass transfer in a LHP cannot be overstated. During the initial spacecraft TCS design phase, trade studies are usually carried out to select an appropriate thermal control concept for the design. The inability to accurately predict the LHP response in the actual operating environment often leads to the dismissal of LHPs for lack of certainty. This paper attempts to present a simplistic explanation of LHP operation in terms of heat and mass transfer processes, in hope that it will help the potential end-users to understand the technology better. Most of the observed phenomena described herein are based on available test data of various LHP systems. Nevertheless, a few anomalies especially during operational transients are still not well understood. For that, research ideas will also be proposed.

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Special Features of the CLUSTER Thermal Control Concept

10.4271/921325 ◽

1992 ◽

Author(s):

Wolfgang Pitz ◽

Hal Scholten ◽

Giacinto Gianfiglio

Keyword(s):

Thermal Control ◽

Control Concept

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Scanning-probe microscope analysis of optical thin films: A new analytical tool in a manufacturing environment

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173078 ◽

1994 ◽

Vol 52 ◽

pp. 1068-1069

Author(s):

S. P. Sapers ◽

R. Clark ◽

P. Somerville

Keyword(s):

Thin Film ◽

Thin Films ◽

Thermal Control ◽

Scanning Probe Microscope ◽

Scanning Probe ◽

List Type ◽

Manufacturing Environment ◽

Physical Measurements ◽

Probe Microscope

OCLI is a leading manufacturer of thin films for optical and thermal control applications. The determination of thin film and substrate topography can be a powerful way to obtain information for deposition process design and control, and about the final thin film device properties. At OCLI we use a scanning probe microscope (SPM) in the analytical lab to obtain qualitative and quantitative data about thin film and substrate surfaces for applications in production and research and development. This manufacturing environment requires a rapid response, and a large degree of flexibility, which poses special challenges for this emerging technology. The types of information the SPM provides can be broken into three categories:(1)Imaging of surface topography for visualization purposes, especially for samples that are not SEM compatible due to size or material constraints;(2)Examination of sample surface features to make physical measurements such as surface roughness, lateral feature spacing, grain size, and surface area;(3)Determination of physical properties such as surface compliance, i.e. “hardness”, surface frictional forces, surface electrical properties.

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