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The fuel economy was estimated at boost trajectory of aerospace plane during energy supply to the free stream. Initial and final velocities of the flight were given. A model of planning flight above cold air in infinite isobaric thermal wake was used. The comparison of fuel consumption was done at optimal trajectories. The calculations were done using a combined power plant consisting of ramjet and liquid-propellant engine. An exergy model was constructed in the first part of the paper for estimating the ramjet thrust and specific impulse. To estimate the aerodynamic drag of aircraft a quadratic dependence on aerodynamic lift is used. The energy for flow heating is obtained at the sacrifice of an equivalent decrease of exergy of combustion products. The dependencies are obtained for increasing the range coefficient of cruise flight at different Mach numbers. In the second part of the paper, a mathematical model is presented for the boost part of the flight trajectory of the flying vehicle and computational results for reducing the fuel expenses at the boost trajectory at a given value of the energy supplied in front of the aircraft.

Oscillations of nonuniform fluidized bed in the slugging regime are considered. A nonlinear one-dimensional model of bed oscillations is developed and investigated, including the equations of the bed surface motion and the oscillations of the pressure drop in the bed for the phase of the surface ascent and for the phase of its fall. A quasi-discrete process of the gas escape from the layer with large bubble and the relaxation (discontinuous) type of oscillations of the bed surface and of the pressure, which are related to the above process, are shown based on the model analysis, the obtained numerical solutions, and the comparison with experiment.

The effect of artificial perturbations on structure formation in the water film flow over a vertical plate with a heater was studied experimentally. To measure the film thickness an eight-channel capacitance probe was used. It is shown that artificial perturbations on the liquid film surface can change the distance between rivulets from the values corresponding to the thermocapillary-wave regime of rivulet formation to the values related to the thermocapillary regime. The distance between the rivulets can be changed at Reynolds numbers higher than those corresponding to the thermocapillary regime. Artificial perturbations do not change significantly the relative amplitude of large waves, but they affect the character of amplitude dependence on the heat flux density.

It is difficult to eliminate the effect of vessel walls and impurities in practical studies of boiling-up of strongly superheated liquids. Therefore, some doubts are always cast upon validity of experiments and their agreement with the classical theory of homogeneous stationary nucleation, impairing the verification of theoretical considerations. This paper reports main results of the theory of homogeneous nucleation and presents formulas for calculating the work of formation of a critical nucleus by an incline of the accessible superheating boundary on isobars and isotherms. Matching of experimental and theoretical values of the work of formation was considered as the homogeneous boiling-up criterion. Calculations by isobars and isotherms were made for some liquids. The theoretical values of the work of formation of a critical nucleus were 1.23-4.5 times higher than the corresponding empirical values for all the liquids, i.e., they were much higher than the calculation error. Thus, boiling-up of the studied liquids was not homogeneous and, hence, it did not correspond to the classical theory of nucleation.

A numerical and analytical model is proposed for the impact of a hollow melt droplet onto the surface of a solid polished substrate. The model is based on integral laws of the mass and energy conservation of the colliding droplet, it accounts for capillary and adhesion properties of the melt. The main parameters of the high-velocity deformation of a hollow particle have been computed: the variation of its height, shell thickness, and the contact spot diameter up to the moment of the spreading droplet solidification as well as the pressure variation inside the droplet until the moment of the shell rupture. The critical pressure value at which the rupture occurs is estimated by a formula characterizing the spherical shell strength. Quite a fair agreement of the computed values of the final diameter of the splat of a spread and solidified droplet with the data of physical experiment  is shown.

The problem of drying a porous permeable material is considered. Self-similar solutions are derived for the process of the moisture diffusion transport. The dependence of drying intensity on the porous medium initial state as well as on the parameters of external effect is investigated.

Based on a mathematical model of a porous reacting medium the statement and mathematical solution are presented for a problem of the peat smoldering rise as a result of the effect of a lower seat of fire. It is found that at moderate temperatures T ≤ 750 K the firing and smoldering of the initial reagent are determined by the intensity of the external burning seat as well as by the processes of the peat drying, pyrolysis, and the oxidation reaction of the coked fixed bed.

Numerical analysis of hemispherical values of absorptive, transmitting, and reflective abilities of a flat layer and absorptivity of a sphere is presented in this paper depending on the optic thickness and refractive index.

Successful experience of RSC "Energy" and SPA "Iskra" in the development of carbon-carbon extension for oxygen-kerosene liquid fuel rocket motor has been summarized. Methodological approach that served to completion of carbon-carbon extension development in full and at comparatively small expenses has been described. Results of practical application of carbon-carbon extension for liquid fuel rocket motor 11D58М have been presented within the framework of International Space Program "Sea Launch".

Thermal diffusivity of polycrystalline tantalum at the temperatures range from 293 to 1800 K has been measured by the laser flash method with the error of 2−4 %. Thermal conductivity has been calculated with the use of reference data on density and heat capacity. Approximating equations and tables of reference data for the temperature dependence of heat transfer coefficients have been obtained; comparison with the published data has been carried out.