Cryogenic Regenerators

Control-oriented Modeling of the Dynamics of Stirling Engine Regenerators

We develop a first-principles model of the regenerator component of a generic Stirling engine. The model is based on the Euler equations of one dimensional gas dynamics coupled with its convective/conductive heat transfer with the embedded mesh material. We investigate various methods for deriving simpler and low order control-oriented models from this first principles model. The basic criterio...

Design of Four-Wave Mixing Frequency-Shift-Free Amplitude Regenerators

Frequency-shift-free all-optical amplitude regenerators based on fiber-four-wave mixing were investigated by means of simulations. These regenerators, comprised of two stages of highly nonlinear dispersion-shifted fiber, were designed using a heuristic procedure that implements a routine based on a genetic algorithm to optimize the device performance. A bit error rate improvement of up to four ...

Receiver Cryogenic System

Cryogenic Model Materials

An overview and status of current activities seeking alternatives to 200 grade 18Ni Steel CVM alloy for cryogenic wind tunnel models is presented. Specific improvements in material selection have been researched including availability, strength, fracture toughness and potential for use in transonic wind tunnel testing. Potential benefits from utilizing damage tolerant life-prediction methods, r...

A Cryogenic Data

A computer storage system which is addressed by content rather than location is described. The design has been verified by constructing and successfully operating a three-word module consisti~g of 81 crossed-film cryotrons on a 6-inch by 3-inch substrate.