The crew exploration vehicle (CEV) service module (SM) main engine plume heating is analyzed using multiple numerical tools. The chemical equilibrium compositions and applications (CEA) code is used to compute the flow field inside the engine nozzle. The plume expansion into ambient atmosphere is simulated using an axisymmetric space-time conservation element and solution element (CE/SE) Euler code, a computational fluid dynamics (CFD) software.
Maintaining low temperature payloads through atmospheric reentry and ground recovery is becoming a larger focus in the space program as work in biology, cryogenic and other temperature dependent sciences becomes a higher goal on the International Space Station (ISS) and extraterrestrial surfaces. Paragon analyzes reentry system thermal control, particularly technology regarding small thermally controlled payloads anticipated for use in sample return from the International Space Station.
This paper describes a new means of analyzing the thermal response of air-cooled and liquid-cooled electronics that overcomes limitations in available tools and current design methods. It also shows how these new tools and methods can extend the reach of such thermal/fluid analyses by helping to size and locate components as well as dealing with both pre-test uncertainties and post-deployment variations in manufacturing, environment, and usage.
Modeling to predict the condition of cryogenic propellants in an upper stage of a launch vehicle is necessary for mission planning and successful execution. Traditionally, this effort was performed using custom, in-house proprietary codes, limiting accessibility and application. Phenomena responsible for influencing the thermodynamic state of the propellant have been characterized as distinct events whose sequence defines a mission. These events include thermal stratification, passive thermal control roll (rotation), slosh, and engine firing.
As air cooling of electronics reaches the limits of its applicability, the next generation of cooling technology is likely to involve heat pipes and single- or two-phase coolant loops (including perhaps loop thermosyphons, spray cooling, vapor compression refrigeration cycles, and loop heat pipes). These technologies are not suitable for analysis using 2D/3D computational fluid dynamics (CFD) software, and yet the geometric complexities of the thermal/structural models make network-style schematic modeling methods cumbersome.