Multi-reactor power system configurations for multimegawatt nuclear electric propulsion

A modular, multi-reactor power system and vehicle configuration for piloted nuclear electric propulsion (NEP) missions to Mars is presented. Such a design could provide enhanced system and mission reliability, allowing a comfortable safety margin for early manned flights, and would allow a range of piloted and cargo missions to be performed with a single power system design. Early use of common power modules for cargo missions would also provide progressive flight experience and validation of standardized systems for use in later piloted applications. System and mission analysis are presented to compare single and multi-reactor configurations for piloted Mars missions. A conceptual design for the Hydra modular multi-reactor NEP vehicle is presented

The 20 kWe NEP system studies

The topics are presented in viewgraph form and include the following: initial study groundrules; power system groundrules/assumptions; power technologies assessment; prototype SP-100 system specific mass; custom SP-100 system specific mass; radiator packaging limits; Brayton system specific mass and radiator area; thermoelectric specific mass and radiator area; specific mass for prototype vs. custom SP-100-based systems; system packaging limits on power level (kWe); and a conceptual nuclear electric propulsion (NEP) science mission spacecraft design

Solid-State Nuclear Power

A strategy for "Solid-State" Nuclear Power is proposed to guide development of technologies and systems into the second 50 years of nuclear spaceflight. The strategy emphasizes a simple and highly integrated system architecture with few moving parts or fluid loops; the leverage of modern advances in materials, manufacturing, semiconductors, microelectromechanical and nanotechnology devices; and the targeted advancement of high temperature nuclear fuels, materials and static power conversion to enable high performance from simple system topologies

The 100-500 kWe NEP systems

Systems technology for nuclear electric propulsion (NEP) vehicles is discussed. The following topics are discussed: the SP-100 reactor; dynamic power conversion; heat rejection; and krypton ion thrusters. The discussion is presented in vugraph form

NEP systems model

A new nuclear electric propulsion (NEP) systems analysis code is discussed. The new code is modular and consists of a driver code and various subsystem models. The code models five different subsystems: (1) reactor/shield; (2) power conversion; (3) heat rejection; (4) power management and distribution (PMAD); and (5) thrusters. The code optimizes for the following design criteria: minimum mass; minimum radiator area; and low mass/low area. The code also optimizes the following parameters: separation distance; temperature ratio; pressure ratio; and transmission frequency. The discussion is presented in vugraph form

Nuclear electric propulsion options for piloted Mars missions

Three nuclear electric propulsion (NEP) systems are discussed. The three systems are as follows: a system based on current SP-100 technology; a potassium Rankine-cycle based power conversion system, and an argon ion thruster system. The system will be researched for implementation in several possible vehicle configurations. The following are among the possible Mars vehicle configurations: a piloted 15 MWe multi-reactor vehicle; a piloted 10 MWe vehicle with ECCV; a piloted 10 MWe modular vehicle; piloted 10 and 15 MWe vehicles with ECCV and MEV; a piloted 5 MWe vehicle with ECCV; a 5 MWe cargo vehicle with 2 MEV's; and a 2.5 MWe vehicle with MEV

Can Leading Indicators Assess Country Vulnerability? Evidence from the 2008-09 Global Financial Crisis

This paper investigates whether leading indicators can help explain the cross-country incidence of the 2008-09 financial crisis. Rather than looking for indicators with specific relevance to the current crisis, the selection of variables is driven by an extensive review of more than eighty papers from the previous literature on early warning indicators. The review suggests that central bank reserves and past movements in the real exchange rate were the two leading indicators that had proven the most useful in explaining crisis incidence across different countries and crises in the past. For the 2008-09 crisis, we use six different variables to measure crisis incidence: drops in GDP and industrial production, currency depreciation, stock market performance, reserve losses, and participation in an IMF program. We find that the level of reserves in 2007 appears as a consistent and statistically significant leading indicator of who got hit by the 2008-09 crisis, in line with the conclusions of the pre-2008 literature. In addition to reserves, recent real appreciation is a statistically significant predictor of devaluation and of a measure of exchange market pressure during the current crisis. So is the exchange rate regime. We define the period of the global financial crisis as running from late 2008 to early 2009, which probably explains why we find stronger results than earlier papers such as Obstfeld, Shambaugh and Taylor (2009, 2010) and Rose and Spiegel (2009a,b) which use annual data

The NAAAA and the NCAA: Methods of Placing Legislation on the Agenda of NCAA Conventions

The authors reviewed the NCAA governance structure and process by which legislation is added to a NCAA agenda to vote. It included how legislation can be authored or sponsored by N4A