Rocket

About: Rocket is a research topic. Over the lifetime, 14018 publications have been published within this topic receiving 95852 citations. The topic is also known as: rockets.

A rocket measurement of the O2(b1Σg+ − X3Σg−) atmospheric band nightglow altitude distribution

Abstract: A rocket measurement of the atmospheric band altitude distribution in the nightglow has been made under high latitude winter conditions An integrated intensity of 14kR was observed with a peak volume emission rate of 750 photons cm-3 sec-1 at 91 km An atomic oxygen altitude distribution with a number density of 17 × 1011 cm-3 at 100 km is derived

A Practical, Affordable Cryogenic Propellant Depot Based on ULA's Flight Experience

Abstract: Mankind is embarking on the next step in the journey of human exploration. We are returning to the moon and eventually moving to Mars and beyond. The current Exploration architecture seeks a balance between the need for a robust infrastructure on the lunar surface, and the performance limitations of Ares I and V. The ability to refuel or top-off propellant tanks from orbital propellant depots offers NASA the opportunity to cost effectively and reliably satisfy these opposing requirements. The ability to cache large orbital quantities of propellant is also an enabling capability for missions to Mars and beyond. This paper describes an option for a propellant depot that enables orbital refueling supporting Exploration, national security, science and other space endeavors. This proposed concept is launched using a single EELV medium class rocket and thus does not require any orbital assembly. The propellant depot provides cryogenic propellant storage that utilizes flight proven technologies augmented with technologies currently under development. The propellant depot system, propellant management, flight experience, and key technologies are also discussed. Options for refueling the propellant depot along with an overview of Exploration architecture impacts are also presented.

Flame stabilization in cryogenic propellant combustion

Abstract: Cryogenic combustion is of considerable technological interest in propulsion applications. Cryogenic propellants used in rocket engines provide the high performance needed for spacecraft launching and have operated safely for a number of years, but the processes that control combustion in such devices are still not well understood. Among the many important issues, flame stabilization constitutes one basic problem. This question is investigated in this article by imaging the flame originating from a single, coaxial injector fed with liquid oxygen and gaseous hydrogen. Results of experiments carried out on a facility for cryogenic propellant combustion research operated by ONERA are used to characterize the mechanisms that control the flame-holding process at atmospheric pressure, 5, and 10 bars. Data acquired correspond to elastic scattering by the spray, emission of OH radicals, and planar laser-induced fluorescence of these radicals. Fluorescence is obtained by pumping the X2II (v″=0)→A2Σ(v′=1) band of OH, and off-resonance light radiation is observed. This database provides the general structure of the flame in the injector near-field, and may be used to determine the position of the flame stabilization region. Simultaneous acquisition of laser-induced fluorescence and elastic scattering was used to locate the flame in respect to the liquid. It is shown that in all cases investigated the flame is initiated at a close distance from the injector exhaust plane.

Prediction of Rocket Plume Flowfields for Infrared Signature Studies

Abstract: The contribution of various gasdynamic processes affecting rocket exhaust plume structure in the altitude range of 0-60 km is discussed in terms of their relative influence on plume infrared radiation signature predictions. It is demonstrated that spatial details of the nearfield inviscid/shock structure in rocket plumes can appreciably affect flight signature levels at higher altitudes (i.e., /?> 30-40 km). Spatial details are also required in the analysis of most laboratory plumes. Simplified gasdynamic models which globally incorporate the effects of inviscid structure into the startline conditions for a pressure-equilibrated farfield mixing analysis are shown to be adequate in flight signature studies at lower altitudes (i.e., h> 20-30 km). The sensitivities of rocket plume emission to variations in turbulence modeling parameters are presented for flight signature studies at representative lower and higher altitudes in the range of interest. It is demonstrated that, under all conditions, turbulent mixing processes play a dominant role in the prediction of plume signature levels.

The quest to conquer Earth's space junk problem.

Abstract: Zombie satellites, rocket shards and collision debris are creating major traffic risks in orbits around the planet. Researchers are working to reduce the threats posed by more than 20,000 objects in space. Zombie satellites, rocket shards and collision debris are creating major traffic risks in orbits around the planet. Researchers are working to reduce the threats posed by more than 20,000 objects in space.