Study of heat transfer processes in the flowing part of hypersonic air-ramjet engine

The technique and results of the experimental-theoretical study of gas dynamics, heat transfer and the structure of gas flow in the flowing channel of a model hypersonic air-ramjet engine are presented for Mach numbers M = (5; 6).

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Investigation of working processes in a flowing channel of ramjet engine

Thermal Science ◽

10.2298/tsci19s2531m ◽

2019 ◽

Vol 23 (Suppl. 2) ◽

pp. 531-536

Author(s):

Eugene Maslov ◽

Valery Faraponov ◽

Vladimir Arkhipov ◽

Irina Zharova ◽

Eugene Kozlov ◽

...

Keyword(s):

Heat Transfer ◽

Temperature Distribution ◽

Mach Number ◽

Gas Dynamics ◽

Gas Flow ◽

Symmetry Axis ◽

Theoretical Study ◽

Number Range ◽

Ramjet Engine ◽

Flowing Channel

The technique and results of experimental-theoretical study of gas-dynamics, heat transfer and the structure of gas-flow in the flowing channel of a ramjet engine in Mach number range M = (5-7) are presented. The temperature distribution along the flowing channel of a ramjet engine was experimentally obtained. The temperature along the wall of the flowing channel of the axisymmetric model was measured using the developed thermo-probe. Distributions of Mach number and temperature along the symmetry axis of the flowing channel of the model are obtained numerically. Comparison of the numerical and experimentally obtained values of the Mach number showed their qualitative agreement.

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Computational study of unsteady gas flow in the combustion chamber of a ramjet engine with heat transfer

Вычислительные технологии ◽

10.25743/ict.2020.25.6.003 ◽

2021 ◽

pp. 50-61

Author(s):

Надежда Петровна Скибина

Keyword(s):

Heat Transfer ◽

Numerical Simulation ◽

Supersonic Flow ◽

Combustion Chamber ◽

Gas Flow ◽

Stokes Equations ◽

Heat Conducting ◽

Measuring Device ◽

Ramjet Engine ◽

Mach Numbers

Проведено численное исследование нестационарного турбулентного сверхзвукового течения в камере сгорания прямоточного воздушно-реактивного двигателя. Описана методика экспериментального измерения температуры на стенке осесимметричного канала в камере сгорания двигателя. Математическое моделирование обтекания исследуемой модели двигателя проводилось для скоростей набегающего потока M = 5 ... 7. Начальные и граничные условия задачи соответствовали реальному аэродинамическому эксперименту. Проанализированы результаты численного расчета. Рассмотрено изменение распределения температуры вдоль стенки канала с течением времени. Проведена оценка согласованности полученных экспериментальных данных с результатами математического моделирования. Purpose. The aim of this study is a numerical simulation of unsteady supersonic gas flow in a working path of ramjet engine under conditions identical to aerodynamic tests. Free stream velocity corresponding to Mach numbers M=5 ... 7 are considered. Methodology. Presented study addresses the methods of physical and numerical simulation. The probing device for thermometric that allows to recording the temperature values along the wall of internal duct was proposed. To describe the motion of a viscous heat-conducting gas the unsteady Reynolds averaged Navier - Stokes equations are considered. The flow turbulence is accounted by the modified SST model. The problem was solved in ANSYS Fluent using finite-volume method. The initial and boundary conditions for unsteady calculation are set according to conditions of real aerodynamic tests. The coupled heat transfer for supersonic flow and elements of ramjet engine model are realized by setting of thermophysical properties of materials. The reliability testing of numerical simulation has been made to compare the results of calculations and the data of thermometric experimental tests. Findings. Numerical simulation of aerodynamic tests for ramjet engine was carried out. The agreement between the results of numerical calculations and experimental measurements for the velocity in the channel under consideration was obtained; the error was shown to be 2%. The temperature values were obtained in the area of contact of the supersonic flow with the surface of the measuring device for the external incident flow velocities for Mach numbers M = 5 ... 7. The process of heating the material in the channel that simulated the section of the engine combustion chamber was analyzed. The temperature distribution was studied depending on the position of the material layer under consideration relative to the contact zone with the flow. Value. In the course of the work, the fields of flow around the model of a ramjet engine were obtained, including the region of supersonic flow in the inner part of axisymmetric channel. The analysis of the temperature fields showed that to improve the quality of the results, it is necessary to take into account the depth of the calorimetric sensor. The obtained results will be used to estimate the time of interaction of the supersonic flow with the fuel surface required to reach the combustion temperature.

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Nonstationary gas-dynamics and local heat transfer in the output channel of the turbocharger compressor

EPJ Web of Conferences ◽

10.1051/epjconf/201919600007 ◽

2019 ◽

Vol 196 ◽

pp. 00007 ◽

Cited By ~ 1

Author(s):

Leonid Plotnikov ◽

Nikita Grigor'ev ◽

Nikolaj Kochev

Keyword(s):

Heat Transfer ◽

Gas Dynamics ◽

Gas Flow ◽

Local Heat Transfer ◽

Local Heat ◽

Measuring System ◽

Rotor Speed ◽

Outlet Channel ◽

Thermomechanical Characteristics ◽

Channel Configuration

Thermomechanical characteristics of the gas flow at the turbocharger compressor outlet largely determine the quality of the intake process in piston engines with boost. The article presents the results of an experimental study of gas-dynamics and heat transfer of gas flows after compression in a turbocharger centrifugal compressor. A brief description of the experimental setup, the configuration of pipes under investigation, the measuring system and the experimental features are given. The studies were carried out on a free compressor, i.e. without considering the piston part. Different conditions in the compressor outlet channel were created by installing special nozzles with different hydraulic resistances. It has been established that the local heat transfer increases from 23 to 46 % with an increase in the turbocharger rotor speed, depending on the outlet channel configuration. It should be noted that an increase in rotor speed is also accompanied by an increase in air flow through the channel. The increase in flow rate was from 10 to 42 %.

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Theoretical study of heat transfer processes in Heusler-type magnetic microwires

Letters on Materials ◽

10.22226/2410-3535-2019-4-395-399 ◽

2019 ◽

Vol 9 (4) ◽

pp. 395-399

Author(s):

Oksana Pavlukhina ◽

Vladimir Sokolovskiy ◽

Vasiliy Buchelnikov ◽

Mikhail Zagrebin

Keyword(s):

Heat Transfer ◽

Theoretical Study ◽

Magnetic Microwires ◽

Transfer Processes

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Modeling Pneumatic Conveyor Duct Wear: A New Approach

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2005-77014 ◽

2005 ◽

Author(s):

Prem Chand ◽

A. C. Saha ◽

Prafull Chand

Keyword(s):

Heat Transfer ◽

Mass Transfer ◽

Material Flow ◽

Gas Flow ◽

Gas Mixture ◽

New Approach ◽

Flow Phenomenon ◽

Transfer Processes ◽

Flow Through ◽

Difficult Situations

It was shown in one of our recent works [1] that, the apparently disconnected items like solid-gas flow phenomenon, duct wear and particle degradation are in fact beautifully connected involving all the three components of transfer processes — heat transfer, mass transfer and momentum transfer. This paper which basically is an extension of our work on Fluid Energy Mill [2] aims at predicting duct wear while transporting solids-gas mixture in pneumatic conveyor even in most difficult situations like flow through bends under interference situation. The paper elaborates the methodology used for wear prediction and highlights the effect of several parameters like material flow rate etc. on the nature and extent of the duct wear.

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The Influence of Droplet Dispersity on Droplet Vaporization in the High-Temperature Wet Gas Flow in the Case of Combined Heating

Sustainability ◽

10.3390/su13073833 ◽

2021 ◽

Vol 13 (7) ◽

pp. 3833

Author(s):

Gintautas Miliauskas ◽

Egidijus Puida ◽

Robertas Poškas ◽

Povilas Poškas

Keyword(s):

Heat Transfer ◽

High Temperature ◽

Phase Change ◽

Flue Gas ◽

Gas Flow ◽

Internal Heat ◽

Radiation Absorption ◽

Water Droplets ◽

Transfer Processes ◽

Equilibrium Evaporation

The change in the thermal and energy state of the water droplet is defined numerically. The influence of droplet dispersity on the interaction of the transfer processes was evaluated. In influence of the Stefan flow was considered as well. The internal heat transfer of the droplet was defined by the combined heat transfer through effective conductivity and radiation model. The results of the numerical modeling of heat and mass transfer in water droplets in a wet flue gas flow of 1000 °C highlight the influence of the variation in heat transfer regimes in the droplet on the interaction of the transfer processes in consistently varying phase change regimes. The results of the investigation shows that the inner heat convection diminishes intensively in the transitional phase change regime because of a rapid slowdown of the slipping droplet in the gas. The radiation absorption in the droplet clearly decreases only at the final stage of equilibrium evaporation. The highlighted regularities of the interaction between combined transfer processes in water droplets are also valid for liquid fuel and other semi-transparent liquids sprayed into high-temperature flue gas flow. However, a qualitative evaluation should consider individual influence of dispersity that different liquids have.

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Experimental research into the methods for controlling the thermal-mechanical characteristics of pulsating gas flows in the intake system of a turbocharged engine model

International Journal of Engine Research ◽

10.1177/1468087420987360 ◽

2021 ◽

pp. 146808742098736

Author(s):

Leonid V Plotnikov

Keyword(s):

Heat Transfer ◽

Gas Dynamics ◽

Gas Flow ◽

Mechanical Characteristics ◽

Local Heat Transfer ◽

Local Heat ◽

Gas Flows ◽

Intake System ◽

Instantaneous Values ◽

Technical Solutions

It is a relevant objective in thermal physics and piston engine construction to develop technical solutions for controlling the gas dynamics and heat exchange of gas flows in the intake system of turbocharged engines in order to improve performance. The article presents other authors’ data on the improvement of processes in the gas exchange systems of piston engines. It also provides a description of experimental set-ups, instruments, measurement tools and research methods for establishing the thermal-mechanical characteristics of pulsating flows in the intake system of a turbocharged engine. The instantaneous values of the gas flow rate and the local heat transfer coefficient were determined using the measured results by applying a constant temperature hot-wire anemometer (H-WA). The article describes technical solutions for influencing the gas dynamics and heat exchange of gas flows by stabilising and turbulising the flow. The regularities of changes in the instantaneous values of the flow velocity, pressure and the local heat transfer coefficient in time for a pulsating gas flow with different intake system configurations are obtained. It is shown that the installation of a levelling grid in the compressor outlet channel leads to the stabilisation of the flow and the suppression of heat transfer in the engine intake system by an average of 15% compared to the base system. It was found that the presence of a channel with grooves in the intake system leads to flow turbulisation and the intensification of heat transfer in the intake system by an average of 25%.

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