scholarly journals Research of Macroscopic Regularities of Heat and Mass Transfer at the Ignition Condition of a Liquid High-Energy Material by an Immersed Source with a Limited Energy Capacity

2014 ◽  
Vol 6 ◽  
pp. 764537 ◽  
Author(s):  
Dmitrii O. Glushkov ◽  
Genii V. Kuznetsov ◽  
Pavel A. Strizhak
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
High Energy ◽  
Energy Capacity ◽  
Ignition Condition ◽  
Limited Energy ◽  
Energy Material ◽  
High Energy Material ◽  
Numerical Research ◽  
Diffusion Convection

We carried out a numerical and experimental investigation of heat and mass transfer at the ignition condition of a liquid high-energy material by a typical immersed source with a limited energy capacity, being a small, intensely heated metallic particle. The numerical research is made on the basis of a model taking into account a group of interrelated physicochemical processes (thermal conductivity, diffusion, convection, mixing, and radiative heat transfer) with phase transitions (evaporation of the liquid and crystallization of the particle's material). We established such terminal conditions for the immersion energy source that prevent inflammation of the high-energy material.

scholarly journals Crystallographic Computing Of The High Energy Material Hmxp

2000 ◽  
Vol 56 (s1) ◽  
pp. s346-s346
Author(s):  
B. Kempa ◽  
V. Thome ◽  
M. Herrmann ◽  
W. Engel
Keyword(s):  
High Energy ◽  
Energy Material ◽  
High Energy Material

Stabilization of an intramolecular hydrogen-bond block in an s-triazine insensitive high-energy material

2019 ◽  
Vol 43 (27) ◽  
pp. 10675-10679 ◽  
Author(s):  
Jie Li ◽  
Shucun Wang ◽  
Longyu Liao ◽  
Qing Ma ◽  
Zhenqi Zhang ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Intramolecular Hydrogen Bond ◽  
High Energy ◽  
Energy Materials ◽  
Face To Face ◽  
High Energy Materials ◽  
Energy Material ◽  
High Energy Material ◽  
Intramolecular Hydrogen

A unique intramolecular hydrogen-bond block was stabilized in s-triazine insensitive high-energy materials with face-to-face stacking.

scholarly journals A novel internal heat recycling concept for reducing energy consumption and increasing flux through three-stage air-gap–water-gap membrane distillation system

2020 ◽  
Vol 20 (7) ◽  
pp. 2858-2874
Author(s):  
Mostafa Abd El-Rady Abu-Zeid ◽  
Xiaolong Lu ◽  
Shaozhe Zhang
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Energy Consumption ◽  
Heat And Mass Transfer ◽  
Waste Heat ◽  
Internal Heat ◽  
High Energy ◽  
Membrane Distillation ◽  
Air Gap ◽  
Air Gap Membrane Distillation

Abstract The low flux and high energy consumption problems of the conventional three-stage air-gap membrane distillation (AG-AG-AG)MD system caused by the low temperature difference between hot and cold feed at both sides of the membrane and high boundary layer thickness were solved successfully by replacing one of the three stages of air gaps by a water gap. The novel three-stage air-gap–water-gap membrane distillation (AG-AG-WG)MD system reduced energy consumption and increased flux due to efficient internal heat recycling by virtue of a water-gap module. Heat and mass transfer in novel and conventional three-stage systems were analyzed theoretically. Under a feed temperature of 45 °C, flow rate of 20 l/h, cooling temperature of 20 °C, and concentration of 340 ppm, the (AG-AG-WG)MD promoted flux by 17.59% and 211.69%, and gained output ratio (GOR) by 60.57% and 204.33% compared with two-stage (AG-WG)MD and one-stage AGMD, respectively. This work demonstrated the important role of a water gap in changing the heat and mass transfer where convection heat transfer across the water gap is faster by 24.17 times than conduction heat transfer through the air gap. The increase in flux and GOR economized the heating energy and decreased waste heat input into the system. Additionally, the number of MD stages could increase the achieving of a high flux with operation stability.

Numerical Research of Heat and Mass Transfer Processes in Water Vapors and Gaseous Thermal Decomposition Products Mixture above the Combustible Wood on the Conditions of Chemical Reaction Termination in it

2014 ◽  
Vol 1040 ◽  
pp. 535-540
Author(s):  
Alena O. Zhdanova ◽  
Genii V. Kuznetsov ◽  
Pavel A. Strizhak
Keyword(s):  
Mass Transfer ◽  
Thermal Decomposition ◽  
Heat And Mass Transfer ◽  
Decomposition Reaction ◽  
Decomposition Products ◽  
Transfer Processes ◽  
Water Vapors ◽  
Mass Transfer Processes ◽  
Thermal Decomposition Products ◽  
Numerical Research

The numerical analysis has been made of complex interrelated heat and mass transfer processes, chemical reactions and phase transformations under the thermal decomposition reaction suppression of typical combustible wood (needles of a pine, fir, fir-tree and larch, branches of a pine, fir, birch and larch, cones of a pine, leaves of aspen) by the “water slug” trace. Characteristic times have been calculated of the thermal decomposition reaction suppression of typical combustible wood at typical temperatures in “water slug” trace and the thickness of warmed material layers.

scholarly journals Thermal effects of high energy and ultrafast lasers

2015 ◽  
Author(s):  
◽  
Nazia Afrin
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Heat Transport ◽  
Phonon Scattering ◽  
Heated Surface ◽  
High Energy ◽  
Electron Interaction ◽  
Energy Laser ◽  
High Energy Laser

Heat transfer describes the exchange of thermal energy, between physical systems depending on the temperature and pressure, by dissipating heat. The fundamental modes of heat transfer are conduction or diffusion, convection and radiation. Heat and mass transfer are kinetic processes that may occur and be studied separately or jointly. Studying them apart is simpler, but both processes are modeled by similar mathematical equation in the case of diffusion and convection. There are complex problems where heat and mass transfer processes are combined with chemical reactions, as in combustion. The resulting behavior of heat transport in microscale will be very different from macroscale heat transfer based on the averages taken over hundreds of thousands of grains (in space) and collision (in time). From the microscopic point of view, the process of heat transport is governed by phonon-electron interaction in metallic films and by phonon scattering in dielectric films, insulators and semi-conductors. For extremely heated surfaces by high energy laser pulse, it is very difficult to measure temperature of flux at the heated surface because of the unendurable capacity of the conventional sensors. Laser is the tool of choice when drill holes ranging in diameter from several millimeters to less than one micro-meter. Instead of having advanced melting and resolidification modeling process recently, the inherent uncertainties of the input parameters can directly cause unstable characteristics of the output results which means the parametric uncertainties may influence the characteristics of the phase change processes (melting and resolidification) which will affect the predictions of interfacial properties i.e., temperature, velocity and mainly the location of solid-liquid interface. All of those processes can be considered under high energy laser interaction with materials.

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