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Limited battery power and poor engine efficiency at cold temperature results in low plug in hybrid vehicle (PHEV) fuel economy and high emissions. Quick rise of battery temperature is not only important to mitigate lithium plating and thus preserve battery life, but also to increase the battery power limits so as to fully achieve fuel economy savings expected from a PHEV. Likewise, it is also important to raise the engine temperature so as to improve engine efficiency (therefore vehicle fuel economy) and to reduce emissions. One method of increasing the temperature of either component is to maximize their usage at cold temperatures thus increasing cumulative heat generating losses. Since both components supply energy to meet road load demand, maximizing the usage of one component would necessarily mean low usage and slow temperature rise of the other component. Thus, a natural trade-off exists between battery and engine warm-up.

Electric power generation and conditioning have experienced revolutionary development over the past two decades. Furthermore, new materials such as high energy magnets and high temperature superconductors are either available or on the horizon. Our work is based on the promise that new technologies are an important driver of new power system concepts and architectures. This observation is born out by the historical evolution of power systems both in terrestrial and aerospace applications. This paper will introduce new approaches to designing space power systems by using several new technologies.

The opportunity for the application of Wireless Power Transmission (WPT) technologies is growing. Applications covering terrestrial, airborne and space missions are evolving. Concepts for terrestrial systems for powering remotely located regions by the use of renewable energy sources; airborne systems used for remote observation, communication relay, and environmental monitoring; and space based systems for potentially powering the elements of a space infrastructure are being developed. This paper will present the history of wireless power transmission systems and summarize current and future applications and technology. Design constraints for terrestrial systems, airborne platforms and space systems will be presented.

The rotary-vee engine is a novel and unusual internal combustion engine. The rotary-vee engine is unique in that all of the components have rotary motion, but the combustion chamber and piston design is similar to a reciprocating engine. Of particular significance, the rotary-vee engine design includes pistons with rings to accomplish the sealing of the combustion chamber. Thus, the rotary-vee engine may offer the sealing benefits of the conventional piston engine, and the vibration and balance characteristics of a rotary engine. This paper includes a review of rotary engines, and places the rotary-vee engine in the context of all rotary engines. In addition, a thermodynamic analysis of the operation of a rotary-vee engine is reported. The rotary-vee engine possesses some advantages relative to other rotary engine designs such as piston ring sealing, and the thermodynamic analysis indicates similar performance as compared to conventional reciprocating engines.

A scoping thermal analysis was done to evaluate the general feasibility of capillary pumped heat engines. The analysis was motivated by recent advances in nanoscale materials science that have made it increasingly practical to manufacture high porosity wicks with a median pore diameter on the order of a few nanometers. Capillary pumped heat engines are shown to be generally feasible for wick evaporation rates equivalent to about 1 watt per square centimeter when wick material thermal conductivity on the order of a few W/m-K is assumed. A compact heat engine architecture, referred to as an integrated capillary engine, is introduced.