ALBERT

Description: Differential cross sections for secondary protons production in 160 Mev proton reactions on various target nuclei, obtaining angular distributions

Description: Constant current sources consisting of sealed ionization chambers for calibrating electrometers

Description: The results of the Trapped Radiation Effects Panel for the Space Environmental Effects on Materials Workshop are presented. The needs of the space community for new data regarding effects of the space environment on materials, including electronics are listed. A series of questions asked of each of the panels at the workshop are addressed. Areas of research which should be pursued to satisfy the requirements for better knowledge of the environment and better understanding of the effects of the energetic charged particle environment on new materials and advanced electronics technology are suggested.

Description: A series of studies were undertaken to measure various parameters such as velocity, species concentration, and temperature downstream of a shear coaxial injector in an optically accessible uni-element rocket chamber. Techniques applied include: laser Doppler velocimetry (LDV) for velocity; laser light scattering (LLS) for flow visualization and estimating mixture fraction and density; laser induced fluorescence (LIF) of hydroxyl radials (OH) to determine the characteristics and extent of the reaction zone; and Raman spectroscopy to measure major species concentration and temperature.

Description: The objective of the current work is to develop an non-intrusive technique to experimentally determine the major species and temperature field in the combustion chamber of a uni-element rocket for a GO2/GH2 propellant combination.

Description: Organic phosphors detection efficiency for neutrons compared with Monte Carlo theretical calculations

Description: The application of laser-based diagnostic techniques has become commonplace to a wide variety of combustion problems. New insights into combustion phenomena at a level previously unattainable has been made possible by non-intrusive measurements of velocity, temperature, and species. However, due to the adverse conditions which exist inside rocket engines, relatively few studies have addressed these combustion environments. The high pressure, high speed, combusting environment in a rocket engine prohibits the application of several measurement techniques. However, in the rocket community, there is a critical need for rocket flow field data to validate computational fluid dynamic (CFD) codes. Currently at Penn State, there is an effort to obtain flowfield measurements inside a rocket engine. Velocity measurements have been made inside the combustion chamber of a uni-element (shear coaxial injector) optically accessible rocket chamber at several axial locations downstream of the injector. These measurements, combined with future measurements, will provide benchmark data for CFD code validation.

Description: The performance and stability of liquid rocket engines is often argued to be significantly impacted by atomization and droplet vaporization processes. In particular, combustion instability phenomena may result from the interactions between the oscillating pressure field present in the rocket combustor and the fuel and oxidizer injection process. Few studies have been conducted to examine the effects of oscillating pressure fields on spray formation and its evolution under rocket engine conditions. The pressure study is intended to address the need for such studies. In particular, two potentially important phenomena are addressed in the present effort. The first involves the enhancement of the atomization process for a liquid jet subjected to an oscillating pressure field of known frequency and amplitude. The objective of this part of the study is to examine the coupling between the pressure field and or the resulting periodically perturbed velocity field on the breakup of the liquid jet. In particular, transverse mode oscillations are of interest since such modes are considered of primary importance in combustion instability phenomena. The second aspect of the project involves the effects of an oscillating pressure on droplet coagulation and secondary atomization. The objective of this study is to examine the conditions under which phenomena following the atomization process are affected by perturbations to the pressure or velocity fields. Both coagulation and represent a coupling mechanism between the pressure field and the energy release process in rocket combustors. It is precisely this coupling which drives combustion instability phenomena. Consequently, the present effort is intended to provide the fundamental insights needed to evaluate these processes as important mechanisms in liquid rocket instability phenomena.

Description: The objective is to establish a major experimental laboratory for studying fundamental processes such as mixing and combustion under liquid rocket engine conditions. The capability of this laboratory will include operation using a variety of fuel and oxidizer systems including liquid oxygen and liquid hydrocarbons. In addition to providing the proper facilities for supplying and controlling these fuels and oxidizers, a specific effort is being made to provide a state-of-the-art diagnostic capability for combustion measurements. In particular, optical and laser-based techniques are being emphasized for measurements of species, velocities, and spray characteristics.

Description: Research efforts are directed towards understanding specific technical issues that must be resolved to minimize the risk and cost associated with developing oxygen-rich rocket preburners. The experiments concentrate on hot-fire uni-element tests to demonstrate concepts which can be incorporated into hardware design and development. Two concepts under consideration are direct injection of propellants at high O/F (oxidizer/fuel ratio), and stoichiometric injection followed by downstream injection of LOX to achieve the high O/F. The specific results given here address the performance, ignition, combustion stability, and wall heat transfer aspects of a direct-injection swirl coaxial element design operating at high O/F.