Search

This publication examines the history of Project Orion and NERVA nuclear engine program within the Integrated Program Plan, the technical reasons for their study, their progress, and the political reasons for their cancellation. Whether pulsed or thermal, nuclear propulsion offers the best compromise in efficiency and thrust for the propulsion of future manned missions. Project Orion was born in the mind of Stanislaw Ulam, an atomic physicist who had worked on the Manhattan project. Despite theoretical performances superior to anything conceivable even with current technologies, and despite the mobilisation of some of the most brilliant physicists of the time (Freeman Dyson), the project was killed by the Treaty banning nuclear weapon tests in the atmosphere, in outer space and under water (Moscow, 5 August 1963). The Integrated Program Plan was Wernher von Braun's proposal to the Space Task Group (STG), chaired by Vice President Spiro Agnew, for the continuation of the Apollo program. This plan envisaged a lunar base in the 1970s, and a first manned mission to Mars in the early 1980s. All of this would have been powered by nuclear-powered orbital shuttles, using NERVA, a nuclear engine tested and operational since 1968. Here again, even though it performed better than anything else in the world, even today, the project failed politically. This retrospective publication therefore aims to answer the following question: How can nuclear space programs of today and tomorrow be protected from the uncertainties of this influence? The study of propulsion systems is very often left to engineers, and political and public relations issues to politicians. However, every technology is the result of a political system, and has a strategic impact, which is a subject for social and political sciences. That's why this paper adopts an original approach crossing social sciences through the historical study of decision-making dynamics, and engineering through the study of the technical characteristics of the projects involved. This publication is based on declassified technical reports, testimonies of the personalities of the time, and a document from the archives of the John F. Kennedy Presidential Library. History can be the academic bridge between political and technical studies. In a context of resurgence of nuclear propulsion projects throughout the world, such an approach is now necessary both at the historical level and in terms of political decisions making. Indeed, space programs involving nuclear energy are, by nature, at the crossroads of public relations issues very specific to both space and atomic subjects. [ABSTRACT FROM AUTHOR]

Abstract: An experimental–computational system, which is developed at the Thermal Laboratory, Department Space Systems Engineering, Moscow Aviation Institute (MAI), is presented for investigating the thermal properties of composite materials by methods of inverse heat transfer problems. The system is aimed at investigating the materials in conditions of unsteady contact and/or radiation heating over a wide range of temperature changes and heating rates in a vacuum, air and inert gas medium. The paper considers the hardware components of the system, including the experiment facility and the automated system of control, measurement, data acquisition and processing, as well as the aspects of methodical support of thermal tests. In the next part the conception and realization of a computer code for experimental data processing to estimate the thermal properties of thermal-insulating materials is given. The most promising direction in further development of methods for non-destructive composite materials using the procedure of solving inverse problems is the simultaneous determination of a combination of their thermal and radiation properties. The general method of iterative regularization is concerned with application to the estimation of materials properties (e.g., example: thermal conductivity and heat capacity ). Such problems are of great practical importance in the study of material properties used as non-destructive surface shield in objects of space engineering, power engineering, etc. In the third part the results of practical implementation of hardware and software presented in the previous two parts are given for the estimating of thermal properties of thermal-insulating materials. The main purpose of this study is to confirm the feasibility and effectiveness of the methods developed and hardware equipment for determining thermal properties of particular modern high porous materials. [Copyright &y& Elsevier]