Furrer D.U.,Aerojet Rocketdyne
Current Opinion in Solid State and Materials Science | Year: 2011
Phase-field modeling methods have advanced to the point where many metallurgical reactions and phenomena can be simulated, including solidification, segregation, precipitation and grain growth to name a few. The ability to predict phases and spatial distribution and concentration of constituent elements in real-world materials is of great interest and importance to industrial engineers. This capability can enable greater understanding of how microstructures and subsequently mechanical properties evolve during complex industrial manufacturing processes. There are numerous examples of phase-field modeling being applied to industrial materials and manufacturing processes. A review of these efforts provides some insight into the capabilities, potential further applications and challenges still ahead for this computational method. © 2011 Elsevier Ltd. All rights reserved.
Cai C.,Aerojet Rocketdyne
Systems and Control Letters | Year: 2011
We consider a class of discrete-time dynamical systems that consist of switching of many linear time-invariant systems, and it can be used to cover a sampled-data version of Switched Linear Systems, which have been widely studied in the literature. For this class of dynamical systems, we establish the LMI (Linear Matrix Inequality) formulation of analyzing their inputoutput stability properties, including both ℓ-2 stability and passivity, by constraining switching signals via the concept of dwell time. The LMI formulation of ℓ-2 stability is applied to evaluating the closed-loop performance of an industrial refrigeration process that is regulated by several proportional-integral (PI) controllers in a switching structure. © 2011 Elsevier B.V. All rights reserved.
Aerojet Rocketdyne | Date: 2015-10-29
An internal combustion engine including a pilot subchamber, a pilot fuel injector having a tip in communication with the pilot subchamber, an ignition element positioned to ignite fuel within the pilot subchamber, and a main fuel injector spaced apart from the pilot fuel injector. The engine includes a common rail in fluid communication with the main fuel injector and with the pilot fuel injector. The internal combustion engine may be a reciprocating engine. A method of combusting fuel in an internal combustion engine is also provided.
Aerojet Rocketdyne | Date: 2016-01-07
Feedback from a solenoid is achieved by adding at least one variable resistance in parallel with the solenoid current feedback circuit for position detection. The resistance has current flowing therethrough when a switching device actuated by the solenoid is in one position or transitions from one position to at least one other position. A feedback current may be measured in the current feedback circuit and the position of the switching device in response to actuation thereof by the solenoid may be determined from the measured feedback current.
Aerojet Rocketdyne | Date: 2015-12-08
An engine mounting arrangement is provided for supporting a gas turbine engine. The mounting arrangement comprises a module adaptor mounted to an overhead or a ground based carrier for rotation about a substantially horizontal axis. The module adaptor extends horizontally from a base to an axially-opposed distal end having a first mounting interface configured for attachment to a module of the engine. The module adaptor holds the engine by the module to which it is attached and with the other engine modules projecting in a cantilever fashion from the supported module.