Demonstrator of continuous-detonation air-breathing ramjet: Wind tunnel data

First experimental investigations were carried out into the detonation combustion of hydrogen in a demonstrator of an original-design air-breathing ramjet while blowing with an air flow at Mach 4 to 8 in an impulse wind tunnel, and for the first time under these conditions, continuous spin and longitudinal pulsed modes of detonation combustion of hydrogen in an annular combustor were detected.     

The dielectric properties of crystal LiNH<Subscript>4</Subscript>SO<Subscript>4</Subscript> in microwave

Temperature dependences of a complex dielectric permittivity of lithium ammonium sulphate LiNH₄SO₄ monocrystal in a frequency range of 3–26 GHz were studied using technique of the cylindrical slot-hole resonator. It was shown that obtained dispersion dependences can be described taking in account the normal distribution of relaxation times.     

Wind Tunnel Testing of a Detonation Ramjet Model at Approach Air Stream Mach Number 5.7 and a Stagnation Temperature of 1500 K

The mode of continuous detonation combustion of hydrogen in the annular combustor of a model of a detonation air-breathing ramjet at the approach air stream Mach number 5.7 and a stagnation temperature of 1500 K was experimentally detected for the first time in a pulsed wind tunnel. The thrust and fuelbased specific impulse of the ramjet model were 1550 N and 3300 s, respectively.     

Spectral-luminescence properties of a number of new heterocyclic compounds in solutions

Results of the spectral-luminescence investigation of solutions of new heterocyclic compounds are given. The relationship between the structure of the heterocyclic compounds and their spectral-luminescence characteristics is analyzed. The concentrations are established beginning with which the concentration quenching of luminescence occurs. Double luminescence manifested by certain compounds is related to their existence in the form of isomers. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 3, pp. 336–339, May–June, 2000.     

Rocket Engine with Continuous Film Detonation of Liquid Fuel

It was experimentally proven for the first time that it is possible to perform continuous detonation combustion of a film of a liquid fuel in the annular combustor of a demonstrator of a liquid-fuel detonation rocket engine. Firing tests revealed a near-limit mode of longitudinally pulsating film detonation and modes of continuous spinning film detonation with one and two detonation waves circulating within the annular gap of the combustor.     

The features of hydrogen ignition over Pt and Pd foils at low pressures

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Shock wave and detonation propagation through U-bend tubes

The objective of the research outlined in this paper is to provide experimental and computational data on initiation, propagation, and stability of gaseous fuel–air detonations in tubes with U-bends implying their use for design optimization of pulse detonation engines (PDEs). The experimental results with the U-bends of two curvatures indicate that, on the one hand, the U-bend of the tube promotes the shock-induced detonation initiation. On the other hand, the detonation wave propagating through the U-bend is subjected to complete decay or temporary attenuation followed by the complete recovery in the straight tube section downstream from the U-bend. Numerical simulation of the process reveals some salient features of transient phenomena in U-tubes.     

Hydrojet engine with pulse detonation combustion of liquid-fuel

An experimental prototype of an engine of a new type for water transport—pulse detonation hydroramjet—was designed, built, and tested for the first time. Firing test of the prototype with a 2-L combustor was performed on a specially designed test stand with a thrust-measuring frame capable of producing an approach water stream in the form of a submerged jet with a velocity up to 10 m/s. The specific impulse was experimentally measured, ranging from 370 s at high operation frequency (20 Hz) to 1200 s at low operation frequency (1 Hz); i.e., the measured specific impulse of the pulse detonation hydroramjet exceeded that of the best modern liquid rocket engines.