Problems of Thermophysics and Thermal Engineering for the New Technologies of the Twenty-First Century

2005 ◽  
Vol 58 (3) ◽  
pp. 206-223 ◽  
Author(s):  
I. Z. Kopp
Keyword(s):  
Heat Transfer ◽  
Power Plants ◽  
Large Scale ◽  
New Technologies ◽  
Review Article ◽  
Thermal Engineering ◽  
Thermal Processes ◽  
Two Phase ◽  
Temperature Plasma ◽  
New Approaches

This review article gives an overview of some topics related to classical and modern problems in the theory of heat, its meaning for various branches, and thermal management of equipment. The specific requirements for new technologies involved in the thermal operation of miniaturized instruments, components of equipment, devices, units operating in fast-response regimes, improvement of heat resistance, reliability, and endurance are considered. Special requirements have been put forward for nanotechnologies, where engineering parts, elements of devices, and technological equipment have microscopic and submicroscopic dimensions. Also, the stringent requirements of thermal modes of modern large-scale technologies in such branches of industry as nuclear power engineering and rocket-space engineering have become more important and determining. The thermal modes of these technologies call for new approaches to the design of the thermodynamic state of micro- and macrosystems, high-temperature plasma, and cryogenic temperatures. New results of the study of the mechanism of heat transfer in phase transitions, principally in new approaches to the problem of enhancement of heat transfer in one- and two-phase flows are presented. The importance of studies of thermal processes providing reliable thermal modes of new power plants, microsystems, and nanotechnologies is shown. The significance of advances in the study of thermal processes for developing the theory of heat is discussed. Especially considered are achievements in the theory of heat for its role in the decisions of actual problems of biology, medicine, and environment. This review article cites 105 references, most of them in Russian.

Experimental study of thermal processes in gaseous methane at its natural convection

2021 ◽  
Author(s):  
V.A. Altunin ◽  
K.V. Altunin ◽  
M.R. Abdullin ◽  
M.R. Chigarev ◽  
I.N. Aliev ◽  
...  
Keyword(s):  
Experimental Study ◽  
Natural Convection ◽  
Power Plants ◽  
New Technologies ◽  
New Technology ◽  
Liquid Hydrocarbon ◽  
Thermal Processes ◽  
Rocket Engines ◽  
Air Jet ◽  
Single Use

The paper discovers the reasons for the transfer of single-use or reusable ground, air, aerospace, and space-based engines and power plants from liquid hydrocarbon fuels and coolers to gaseous fuels, or rather, to liquefied natural gas methane. The study gives specific examples of creating a new technology and using methane fuel and fuel in the existing units; lists the classes of methane engines and power plants, among which the main ones being piston engines and internal combustion power plants, air-jet engines and power plants, liquid propellant rocket engines and power plants. Findings of research show that it is necessary to experimentally study gaseous methane, so that it could be effectively used in advanced single-use or reusable ground, air, aerospace and space-based engines and power plants, and their features should be taken into account when designing and developing new technologies. The study introduces the results of the experimental study of thermal processes in gaseous methane during its natural convection, describes the experimental base in detail, as well as the procedure for conducting experiments, and develops methods for calculating the heat transfer coefficient to gaseous methane relying on the research results.

Dropwise Condensation on Carbon Steel Surface

2016 ◽  
Author(s):  
Fangyu Cao ◽  
Sean Hoenig ◽  
Chien-hua Chen
Keyword(s):  
Heat Transfer ◽  
Carbon Steel ◽  
Power Plants ◽  
Heat Dissipation ◽  
Low Cost ◽  
Condensation Heat Transfer ◽  
Working Fluid ◽  
High Heat Flux ◽  
Dropwise Condensation ◽  
Two Phase

The increasing demand of heat dissipation in power plants has pushed the limits of current two-phase thermal technologies such as heat pipes and vapor chambers. One of the most obvious areas for thermal improvement is centered on the high heat flux condensers including improved evaporators, thermal interfaces, etc, with low cost materials and surface treatment. Dropwise condensation has shown the ability to increase condensation heat transfer coefficient by an order of magnitude over conventional filmwise condensation. Current dropwise condensation research is focused on Cu and other special metals, the cost of which limits its application in the scale of commercial power plants. Presented here is a general use of self-assembled monolayer coatings to promote dropwise condensation on low-cost steel-based surfaces. Together with inhibitors in the working fluid, the surface of condenser is protected by hydrophobic coating, and the condensation heat transfer is promoted on carbon steel surfaces.

Methods for calculating thermal processes under conditions of natural convection of gaseous methane under the influence of electrostatic fields

2021 ◽  
Author(s):  
V.A. Altunin ◽  
K.V. Altunin ◽  
M.R. Abdullin ◽  
M.R. Chigarev ◽  
I.N. Aliev ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Natural Convection ◽  
Power Plants ◽  
Experimental Studies ◽  
Thermal Processes ◽  
Technical Literature ◽  
New Methods ◽  
Electric Wind ◽  
Electrostatic Fields ◽  
General Method

Relying on the review and analysis of scientific and technical literature, as well as the results of experimental studies, we developed new methods for calculating thermal processes occurring in gaseous methane during its natural convection, under the influence of electrostatic fields. In this study we show methods for calculating and determining the coefficients of heat transfer to gaseous methane under the influence of electric wind, as well as methods for calculating and determining the effect of electrostatic fields on the negative process of sedimentation on a heated experimental working plate in the volume of gaseous methane. A general method has been developed for the effective and safe application of electrostatic fields in gaseous methane, which must be carried out in the calculations, design, creation, and operation of new engines, power plants, and techno systems for single and reusable ground, air, aerospace and space-based aircraft.

Development of a Thermal Energy Storage System for Parabolic Trough Power Plants With Direct Steam Generation

2010 ◽  
Vol 132 (2) ◽  
Author(s):  
Doerte Laing ◽  
Thomas Bauer ◽  
Dorothea Lehmann ◽  
Carsten Bahl
Keyword(s):  
Heat Transfer ◽  
Power Plants ◽  
Storage System ◽  
Thermal Power ◽  
Sensible Heat ◽  
Steam Generation ◽  
Parabolic Trough ◽  
Two Phase ◽  
Solar Thermal Power ◽  
Direct Steam

For future parabolic trough plants direct steam generation in the absorber pipes is a promising option for reducing the costs of solar thermal power generation. These new solar thermal power plants require innovative storage concepts, where the two-phase heat transfer fluid poses a major challenge. A three-part storage system is proposed where a phase change material (PCM) storage will be deployed for the two-phase evaporation, while concrete storage will be used for storing sensible heat, i.e., for preheating of water and superheating of steam. A pinch analysis helps to recognize interface constraints imposed by the solar field and the power block and describes a way to dimension the latent and sensible components. Laboratory test results of a PCM test module with ∼140 kgNaNO3, applying the sandwich concept for enhancement of heat transfer, are presented, proving the expected capacity and power density. The concrete storage material for sensible heat was improved to allow the operation up to 500°C for direct steam generation. A storage system with a total storage capacity of ∼1 MWh is described, combining a PCM module and a concrete module, which will be tested in 2009 under real steam conditions around 100 bars.

Numerical Investigation on Pool Boiling Over a Vertical Tube Coupled With In-Tube Condensation

2019 ◽  
Author(s):  
Shuai Ren ◽  
Wenzhong Zhou
Keyword(s):  
Heat Transfer ◽  
Phase Change ◽  
Boiling Heat Transfer ◽  
Power Plants ◽  
Pool Boiling ◽  
Heat Removal ◽  
Vertical Tube ◽  
Two Phase ◽  
Maximum Heat ◽  
Maximum Heat Transfer

Abstract Pool boiling and in-tube condensation phenomena have been investigated intensively during the past decades, due to the superior heat transfer capacity of the phase change process. In passive heat removal heat exchangers of nuclear power plants, the two phase-change phenomena usually occur simultaneously on both sides of the tube wall to achieve the maximum heat transfer efficiency. However, the studies on the effects of in-tube condensation on external pool boiling heat transfer are very limited, especially in numerical computation aspect. In the present study, the saturated pooling boiling over a vertical tube under the influences of in-tube steam condensation is investigated numerically. The Volume of Fluid (VOF) interface tracking method is employed based on the 2D axisymmetric Euler-Euler multiphase frame. The phase change model combining with a mathematical smoothing algorithm and a temporal relaxation procedure has been implemented into CFD platform by user defined functions (UDFs). The two-phase flow pattern and bubble behavior have been analyzed. The effects of inlet steam mass flow rate on boiling heat transfer are discussed.

Development of a Thermal Energy Storage System for Parabolic Trough Power Plants With Direct Steam Generation

2009 ◽  
Author(s):  
Doerte Laing ◽  
Thomas Bauer ◽  
Dorothea Lehmann ◽  
Carsten Bahl
Keyword(s):  
Heat Transfer ◽  
Power Plants ◽  
Storage System ◽  
Thermal Power ◽  
Sensible Heat ◽  
Steam Generation ◽  
Parabolic Trough ◽  
Two Phase ◽  
Solar Thermal Power ◽  
Direct Steam

For future parabolic trough plants direct steam generation in the absorber pipes is a promising option for reducing the costs of solar thermal power generation. These new solar thermal power plants require innovative storage concepts, where the two phase heat transfer fluid poses a major challenge. A three-part storage system is proposed where a phase change material (PCM) storage will be deployed for the two-phase evaporation, while concrete storage will be used for storing sensible heat, i.e. for preheating of water and superheating of steam. A pinch analysis helps to recognize interface constraints imposed by the solar field and the power block and describes a way to dimension the latent and sensible components. Laboratory test results of a PCM test module with approx. 140 kg NaNO3, applying the sandwich concept for enhancement of heat transfer, are presented, proving the expected capacity and power density. The concrete storage material for sensible heat was improved to allow the operation up to 500 °C for direct steam generation. A storage system with a total storage capacity of approx. 1 MWh is described, combining a PCM module and a concrete module, which will be tested in 2009 under real steam conditions around 100 bar.

Small Diameter Effects on Internal Flow Boiling

2001 ◽  
Author(s):  
Gail E. Kendall ◽  
Peter Griffith ◽  
Arthur E. Bergles ◽  
John H. Lienhard
Keyword(s):  
Heat Transfer ◽  
Thermal Management ◽  
Nuclear Power ◽  
Power Plants ◽  
Flow Instability ◽  
Flow Boiling ◽  
Small Diameter ◽  
Internal Flow ◽  
Two Phase ◽  
Wide Range

Abstract Since the 1950’s, the research and industrial communities have developed a body of experimental data and set of analytical tools and correlations for two-phase flow and heat transfer in passages having hydraulic diameter greater than 6 mm or so. These tools include flow regime maps, pressure drop and heat transfer correlations, and critical heat flux limits, as well as strategies for robust thermal management of HVAC systems, electronics, and nuclear power plants. Designers of small systems with thermal management by phase change will need analogous tools to predict and optimize thermal behavior in the mesoscale and smaller sizes. Such systems include a wide range of devices for computation, measurement, and actuation in environments that range from office space to outer space and living systems. This paper examines important proceses that must be considered when channel diameters decrease, including flow distribution issues in single, parallel, and split flows; flow instability in parallel passages; manufacturing tolerances effects; nucleation processes; and wall conductance effects. The discussion focuses on engineering issues for the design of practical systems.

Molecular-to-Large-Scale Heat Transfer With Multiphase Interfaces: Current Status and New Directions

2009 ◽  
Vol 131 (12) ◽  
Author(s):  
Raj M. Manglik ◽  
Milind A. Jog
Keyword(s):  
Heat Transfer ◽  
Large Scale ◽  
Film Coating ◽  
Spray Cooling ◽  
Current Status ◽  
Experimental Investigations ◽  
Interfacial Behavior ◽  
Two Phase ◽  
New Directions ◽  
Momentum And Heat Transfer

The scientific understanding of multiphase interfaces and the associated convective mass, momentum, and heat transport across and along their boundaries, provide the fundamental underpinnings of the advancement of boiling heat transfer, two-phase flows, heat pipes, spray cooling, and droplet-film coating, among many other engineering applications. Numerous studies have tried to characterize the interfacial behavior and model their mechanistic influences either directly or implicitly via parametric experimental investigations and/or simulations. The goal of advancing our understanding as well as developing generalized, perhaps “universal,” and more accurate phenomenological or mechanistic correlations, for predicting mass, momentum, and heat transfer, continues to engage the worldwide research community. A collection of some such current investigations that are representative of both basic and applied issues in the field is presented in this special issue of the Journal of Heat Transfer.

Experimental Investigation on Heat Transfer for Two-Phase Flow Under Natural Convection

2012 ◽  
Author(s):  
Milan Amižić ◽  
Estelle Guyez ◽  
Jean-Marie Seiler
Keyword(s):  
Heat Transfer ◽  
Experimental Investigation ◽  
Nuclear Power ◽  
Power Plants ◽  
Liquid Pool ◽  
Severe Accident ◽  
Bottom Plate ◽  
Interfacial Region ◽  
Two Phase ◽  
Wide Range

In the frame of severe accident research for the second and the third generation of nuclear power plants, some aspects of the concrete cavity ablation during the molten corium–concrete interaction are still remaining issues. The determination of heat transfer along the interfacial region between the molten corium pool and the ablating basemat concrete is crucial for the assessment of concrete ablation progression and eventually the basemat melt-through. For the purpose of experimental investigation of thermal-hydraulics inside a liquid pool agitated by gas bubbles, the CLARA project has been launched jointly by CEA, EDF, IRSN, GDF-Suez and SARNET. The CLARA experiments are performed using simulant materials and they reveal the influence of superficial gas velocity, liquid viscosity and pool geometry on the heat transfer coefficient between the internally heated liquid pool and vertical and horizontal pool walls maintained at uniform temperature. The first test campaign has been conducted with the smallest pool configuration (50 cm × 25 cm × 25 cm). The tests have been performed with liquids covering a wide range of dynamic viscosity from approximately 1 mPa s to 10000 mPa s. This paper presents some preliminary conclusions deduced from the experiments which involve a liquid pool with the gas injection only from the bottom plate. A comparison with existing models for the assessment of heat transfer has also been carried out.

Experimental study of electrostatic fields influencing thermal processes in gaseous methane at its natural convection

2021 ◽  
Author(s):  
V.A. Altunin ◽  
K.V. Altunin ◽  
M.R. Abdullin ◽  
M.R. Chigarev ◽  
I.N. Aliev ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Natural Convection ◽  
Power Plants ◽  
Discharge Zone ◽  
Thermal Processes ◽  
Electrostatic Fields ◽  
Experimental Base ◽  
Gaseous Media ◽  
History Of ◽  
The Heat Transfer Coefficient

The paper shows the history of studying electrostatic fields in various gaseous media, including gaseous methane, and substantiates the necessity to experimentally study electrostatic fields influencing thermal processes in gaseous methane at its natural convection. We describe the experimental base and working areas with the use of electrostatic fields, as well as the method of conducting experimental research. The results of the influence of electrostatic fields on the coefficient of heat transfer to gaseous methane and on the negative process of sedimentation in it — during its natural convection are presented. In our research, we found zones of possible intensification of heat transfer to gaseous methane and zones of saturation with electrostatic fields, in which a further increase in the heat transfer coefficient is impossible. We experimentally established that the boundary of the zone of the beginning of saturation with electrostatic fields is also the beginning of the corona discharge zone. The research results formed the basis for the method of using electrostatic fields in aircraft engines and power plants.

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