-
Lecture Notes in Engineering and Computer Science. 01/2009;
-
[show abstract]
[hide abstract]
ABSTRACT: Achieving the highest possible specific impulse has long been a key driver for space launch systems. Recently, more importance has been placed on the need for increased reliability and streamlined launch operations. These general factors along with more specific mission requirements have provided a new focus that is centered on the oxidizer rich staged combustion (ORSC) cycle. Despite a history of use in Russia that extends back to the 1960's, a proven design methodology for ORSC cycle engines does not exist in the West. This lack of design expertise extends to the main chamber injector, a critical subcomponent that largely determines the engine performance and main chamber life. The goals of the effort described here are to establish an empirical knowledge base to provide a fundamental understanding of main chamber injectors and for verification of an injector design methodology for the ORSC cycle. The design of a baseline injector element, derived from information on Russian engines in the open literature, is presented. The baseline injector comprises a gaseous oxidizer core flow and an annular swirling fuel flow. Sets of equations describing the steady-state and the dynamic characteristics of the injector are presented; these equations, which form the basis of the design analysis methodology, will be verified in tests later this year. On-going cold flow studies, using nitrogen and water as simulants, are described which indicate highly atomized and symmetric sprays.
08/2003;
-
[show abstract]
[hide abstract]
ABSTRACT: An impedance bridge for high-voltage capacitance and related measurements to an accuracy of 1 ppm is described and the background research and development which made it possible is documented. The bridge is of the transformer-ratioarm type, the principal components of which are a comparator and several two-stage transformers. The bridge can be used to measure capacitance ratios over a range from 1/1 to 107/1 with a resolution between 0.1 and 0.25 ppm. The highest accuracies are obtained at the principal power frequencies of 50-60 Hz, but the bridge is usable up to 400 Hz. The factors which limited the accuracy of previously developed bridges of this type were reexamined and their influence reduced. Two independent methods were developed for the calibration of the bridge.
IEEE Transactions on Instrumentation and Measurement 01/1976; · 1.21 Impact Factor
-
The Yale journal of biology and medicine 01/1933; 5(3):235-67.
-
Science 08/1929; 70(1804):98-9. · 31.20 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Rats first fed soybean oil and peanut oil diets, then subjected to the process of fat depletion through selective starvation, involving 23 to 27 per cent. loss in body weight, before being fed a "hardening" diet, yielded "harder" fats-fats of lower iodine number values-than the fats of rats which were not starved before being fed the carbohydrate-rich diet. In other words, through the process of starvation, the "soft" oily fat produced on diets containing soybean' or peanut oils is very largely removed, thereby permitting the deposit of a "hard" fat. To obtain a fat of equal "hardness" from rats which were not subjected to the starvation treatment would have required a much longer period of feeding of the diet rich in starch than was found necessary with rats after first being starved. The growth of recovery made by the rats of the starved lots was made on a low food intake. With the starved rats flrst fed peanut oil, the food intake of the carbohydrate-rich diet was less than with the non-starved group. The possible application of these findings to practical animal husbandry is obvious.
Science 11/1926; 64(1659):384-6. · 31.20 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: For future airbreathing and rocket propulsion systems gelled propellants can be a promising replacement for conventional propellants. Especially for rocket engines, the application of a gelled fuel and gelled oxidizer can combine the advantages of conventional solid and liquid propellants without taking into account the specific disadvantages of both individual systems. The present publication describes the rheological behavior of gelled JP-8 turbine fuel and gelled rocket propellant RP-1, whereas fumed silica as a gelling agent has been used. Alongside the determination of an optimal mixing process, the rheological parameters of the investigated gelled hydrocarbon fuels showed a significant influence of the added amount of silica in comparison to the ungelled pure liquids.
International Conference on Chemical Engineering (ICCE'09) within The World Congress on Engineering and Computer Science 2009 (WCECS 2009);
