Active heat exchange system development for latent heat thermal energy storage

Active heat exchange concepts for use with thermal energy storage systems in the temperature range of 250 C to 350 C, using the heat of fusion of molten salts for storing thermal energy are described. Salt mixtures that freeze and melt in appropriate ranges are identified and are evaluated for physico-chemical, economic, corrosive and safety characteristics. Eight active heat exchange concepts for heat transfer during solidification are conceived and conceptually designed for use with selected storage media. The concepts are analyzed for their scalability, maintenance, safety, technological development and costs. A model for estimating and scaling storage system costs is developed and is used for economic evaluation of salt mixtures and heat exchange concepts for a large scale application. The importance of comparing salts and heat exchange concepts on a total system cost basis, rather than the component cost basis alone, is pointed out. The heat exchange concepts were sized and compared for 6.5 MPa/281 C steam conditions and a 1000 MW(t) heat rate for six hours. A cost sensitivity analysis for other design conditions is also carried out

Advanced expander test bed program

The Advanced Expander Test Bed (AETB) is a key element in NASA's Chemical Transfer Propulsion Program for development and demonstration of expander cycle oxygen/hydrogen engine technology component technology for the next space engine. The AETB will be used to validate the high-pressure expander cycle concept, investigate system interactions, and conduct investigations of advanced missions focused components and new health monitoring techniques. The split-expander cycle AETB will operate at combustion chamber pressures up to 1200 psia with propellant flow rates equivalent to 20,000 lbf vacuum thrust

Systemic Innovation in a Distributed Network Paradox or Pinnacle?

Previous research has suggested that there is a dichotomy of organisational practices: companies involved in autonomous or modularised innovations, it is argued, benefit from decentralised approaches where coordination primarily takes place through the marketplace, whereas the benefits of systemic innovation are said to be appropriated best by centralised organisations. However, case studies of subcontractors to the Danish wind turbine industry suggest that the ability to meet heterogeneous demands plays an important role for the success of different forms of organisational practices in relation to innovation. The modularised versus systemic architecture approach therefore appears to be a too sweeping dichotomy for describing what can better be perceived as an array of different practices for balancing innovation contribution with the ability of individual firms to appropriate innovation benefits – and a heterogeneous market perception is a core element in building and sustaining this ability.Organisational Forms, Innovation System, Knowledge Complementarities, Value Appropriation