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Numerous workers have made effort to harness the flexibility of spreadsheets to analyse thermal problems. One approach has been to execute a thermal analysis within the spreadsheet itself, however the usefulness is limited by the performance of the built-in solvers. In addition, spreadsheets must either be custom built for each application or founded on parameterised models from similar analyses. An alternate approach has been to add spreadsheet like capability to existing tools. Again, this loses the full flexibility of a spreadsheet. To overcome these limitations, ThermXL has been developed. ThermXL is a thermal lumped parameter network solver and generic model builder that is fully integrated within Microsoft® Excel. It is very flexible easy-to-use tool that is particularly suited to preliminary design and “What if…?” type parametric analyses. This paper describes the utility, functionality and architecture of ThermXL.

The increasing concern in the space debris to spacecraft, above all long-term missions as the international space station, has increased the demand of reliable analysis tools, raised from industry and agencies. The improvement of environment models and hypervelocity impact predictions has increased the physical available knowledge to software designers. The DEBRIS application of ESABASE is a software simulation tool to assess the number of impacts and the resulting damage from meteoroids and space debris particles to spacecraft in low Earth orbit for user specified mission parameters and shielding designs. The tool is based on existing environment flux and damage models. For space debris this includes the new NASA engineering model ORDEM 96. For meteoroids the models includes streams, directional effects and velocity distributions. Secondary ejecta are also modelled and it is possible for the user to define his own damage equations for the analysis.

During the early phases of a design, where multiple scenarios and multiple configurations are considered, classic thermal analysis processes are far from ideal. It is desirable to be able to turn-around results in a couple of minutes rather than hours or days when evaluating ideas and available options. This paper presents the results of an initial study into developing such capability within a spreadsheet by building on the existing tool ThermXL.

Typically the thermal engineer must consider a wide range of operating and non-operating conditions for a system and needs to understand how various features of the system impact on the overall thermal performance. The task of post-processing and analyzing all the results is often cumbersome and time consuming, usually involving a discrete set of software tools, with the results being manually compiled into a final report for communication to the project team and customer. A new tool, ESATAN/ThermNV (Thermal Network Viewer), was released in 2004 to provide model validation and support some common post-processing tasks. The tool has been very significantly extended during 2005 with developments aimed mainly at strengthening the post-processing capabilities and semiautomation in the generation of analysis reports. As well as built-in post-processing capabilities for standard calculations, a very flexible system of user extensible “calculators” has been included.

The thermal analysis tool set ESARAD and ESATAN/ FHTS is the de facto standard for work in the field of Spacecraft Thermal Analysis within Europe and has a growing user base in many other parts of the world and in other industries. The tools combine the easy access of a modern and intuitive interface with the underlying flexibility of a powerful language ensuring that all engineers, from occasional user to the expert specialist, are equally well served. Many new and exciting developments have been made in this tool set during the last year to improve productivity and the scope and quality of the information generated for the thermal engineer. This paper presents an overview of the key features in the context of realistic engineering scenarios.