Ignition Delay Times of Kerosene (Jet-A)/Air Mixtures

Ignition of Jet-A/air mixtures was studied behind reflected shock waves. Heating of shock tube at temperature of 150 C was used to prepare a homogeneous fuel mixture. Ignition delay times were measured from OH emission at 309 nm and from absorption of He-Ne laser radiation at 3.3922 micrometers. The conditions behind shock waves were calculated by one-dimensional shock wave theory from initial conditions T1, P1, mixture composition and incident shock wave velocity. The ignition delay times were obtained at two fixed pressures 10, 20 atm for lean, stoichiometric and rich mixtures (ER=0.5, 1, 2) at an overall temperature range of 1040-1380 K.Comment: V.P. Zhukov, V.A. Sechenov, and A.Yu. Starikovskii, Ignition Delay Times of Kerosene(Jet-A)/Air Mixtures, 31st Symposium on Combustion, Heidelberg, Germany, August 6-11, 200

Localized pulsed nanosecond discharges in a counterflow nonpremixed flame environment

A flame is a very unusual environment for the development of a gas discharge, since it presents strong gradients in temperature, composition, and pre-ionization. In this paper we examine how such an environment impacts the development of the plasma when using repetitive pulsed nanosecond discharges, one of the main strategies used in the field of plasma assisted combustion. Experiments were performed in a counterflow nonpremixed burner with parallel electrodes at the nozzle exits and nanosecond-resolved photography of the plasma emission is presented. It was shown that the discharge development in stratified media may take place in the form of a dielectric barrier discharge with a localized energy deposition. In the experiments presented the discharge energy was coupled to the flame front because of the high rate of chemi-ionization and the gas density decrease in the flame

Plasma–liquid interactions: a review and roadmap

Plasma–liquid interactions represent a growing interdisciplinary area of research involving plasma science, fluid dynamics, heat and mass transfer, photolysis, multiphase chemistry and aerosol science. This review provides an assessment of the state-of-the-art of this multidisciplinary area and identifies the key research challenges. The developments in diagnostics, modeling and further extensions of cross section and reaction rate databases that are necessary to address these challenges are discussed. The review focusses on non-equilibrium plasmas

Safety for Low-Cost RFID Tags Using Lightweight Authentication Protocol

In this article we consider the actual problem of safety for Low-Cost RFID Tags which are used pretty often in an everyday life, for example in shops. Thus the basic complexity consists that Low-Cost RFID Tags are limited in resources and as consequence, cannot support strong cryptography. Therefore for Low-Cost RFID Tags it is expedient to use the special lightweight algorithms and protocols which should be developed taking into account functional limitation of RFID Tags. We produce one of possible authentication protocol which can be applied as the lightweight protocol to use in Low-Cost RFID Tags, and also we will result its comparative analysis with other authentication protocols developed earlier

Ignition Delay Times of Jet-A/Air Mixtures

Ignition of Jet-A/air mixtures was studied behind reflected shock waves. Heating of shock tube at temperature of 150 °C was used to prepare a homogeneous fuel mixture. Ignition delay times were measured from OH emission at 309 nm (A2Σ – X2Π) and from absorption of He-Ne laser radiation at 3.3922 μm. The conditions behind shock waves were calculated by one-dimensional shock wave theory from initial conditions T1, P1, mixture composition and incident shock wave velocity. The ignition delay times were obtained at two fixed pressures 10, 20 atm for lean, stoichiometric and rich mixtures (ø=0.5, 1, 2) at an overall temperature range of 1040-1380 K

MODEL OF EVALUATING THE LEVEL OF PARASITIC PHASE FLUCTUATIONS IN THE OUTPUT SIGNAL OF THE FREQUENCIES SYNTHESIZER

The article describes the actual problem of calculating the level of parasitic fluctuations of the phase of the output signal of the frequency synthesizer of indirect synthesis based on phase-locked loop. The basis for constructing a polynomial model is the model of output noise distribution based on the Leeson generator principle. The described principles of operation of frequency synthesizers with a divider with a fractionally variable division factor allow us to understand the nature of the appearance of the so-called shot noise. The analysis of the characteristics of all the elements included in the frequency synthesizers makes it possible to ensure that the noise components of each individual unit can be represented as a polynomial. The possibility of using the developed polynomial model for estimating the noise level in frequency synthesizers at the stage of selecting the structure of the proposed implementation structure is proposed. As a demonstration of the adequacy of theoretical calculations, the results of phase noise simulation by the polynomial method for all circuit components are presented, as well as a comparison of the results obtained with the simulation of a similar frequency synthesizer in the «ADIsimPLL» simulation package from Analog Devices. Such a simulation allows not only to obtain the level of side components in the spectrum of the output signal, but also to estimate the degree of influence of each specific element of the circuit