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Special Issue "Selected Papers from The XI International Conference on Computational Heat, Mass and Momentum Transfer (ICCHMT 2018)"

A special issue of Energies (ISSN 1996-1073).

Deadline for manuscript submissions: closed (30 October 2018)

Special Issue Editors

Guest Editor
Prof. Dr. Inż Jan Taler

Politechnika Krakowska, Institute of Thermal Power Engineering, 31-864 Krakow, Poland
Website | E-Mail
Interests: power engineering; thermodynamics; heat transfer; inverse heat transfer problems; steam boiler dynamics; thermal stresses
Guest Editor
Dr. Paweł Ocłoń

Institute of Thermal Power Engineering, Politechnika Krakowska, Krakow, Poland
Website | E-Mail
Interests: finite element analysis; fluid mechanics; modelling and simulation; computational fluid dynamics
Guest Editor
Dr. Marcin Trojan

Cracow University of Technology, Institute of Thermal Power Engineering
Website | E-Mail
Interests: energy engineering; energy systems; heat transfer
Guest Editor
Prof. Dr. Abdulmajeed A. Mohamad

Department of Mechanical and Manufacturing Engineering, University of Calgary, T2N 1N4 Calgary, AB, Canada
Website | E-Mail
Interests: complex transport phenomena; fluid saturating porous medium; energy systems; double diffusion systems; micro-gravity; nanofluids; microfluidics

Special Issue Information

Dear Colleagues,

ICCHMT is an international conference series that is widely recognized and respected in the international scientific community. ICCHMT is founded by Professor Abdulmajeed A. Mohamad from University of Calgary and for nearly 20 years takes place in a different parts of the world: Magusa, Cyprus (1999), Rio de Janeiro, Brazil (2001), Banff, Canada (2003), Paris, France (2005), Canmore, Canada (2007), Guangzhou, China (2009), Istambul, Turkey (2011, 2015), Cracow, Poland (2016), Seul, South Korea (2017). In 2018 the Conference is held in Cracow, Poland. The conference topics dedicated to energy topics are:

  • Heat Exchangers / Heat Pipe
  • Fluid Machinery
  • Internal Flow and Heat Transfer
  • Micro / Nano Heat and Mass Transfer
  • Mixing Devices and Phenomena
  • Multi-Phase Flows
  • Reactive Flows and Combustion
  • Steam and Gas Turbines
  • Technology for Renewable Energy Sources
  • Thermal Flow Visualization
  • Thermal Fluid Machinery
  • Transport Phenomena in Porous Media
  • Waste Management and Waste Disposal

Therefore, the manuscripts within those research area are highly welcome.

Prof. Dr. Jan Taler
Prof. Dr. Paweł Ocłoń
Dr. Marcin Trojan
Prof. Abdulmajeed A. Mohamad
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1800 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Energy systems
  • Energy machinery
  • Thermal Power Plants
  • Thermodynamics
  • Energy efficiency in buildings

Published Papers (10 papers)

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Research

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Open AccessArticle
Trombe Wall Utilization for Cold and Hot Climate Conditions
Energies 2019, 12(2), 285; https://doi.org/10.3390/en12020285
Received: 2 December 2018 / Revised: 11 January 2019 / Accepted: 13 January 2019 / Published: 17 January 2019
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Abstract
In this paper, a novel design for heating and ventilating rooms using solar energy in the winter season and for reducing the cooling load in the summer season is suggested. The system utilizes a water tank, which is part of the building’s wall, [...] Read more.
In this paper, a novel design for heating and ventilating rooms using solar energy in the winter season and for reducing the cooling load in the summer season is suggested. The system utilizes a water tank, which is part of the building’s wall, for storage and hot water supply. The proposed passive system can be used for heating a room in the day and if the heat is available in excess, at night too. The excess heat can also be utilized to heat water for domestic applications. In the summer season, the excess heat can passively ventilate a room and be extracted out of the building. In addition, as mentioned earlier, the heated water by solar energy can be used for domestic purposes such as washing and taking showers. Hence, it helps in reducing the cooling load in the summer season. This article introduces an analysis of the feasibility of the suggested system. The proposed system has many advantages: The modified Tromble wall system is more thermally efficient, is lighter, and has a fast response for charging and discharging processes as compared to the conventional Trombe walls. The mathematical model of the modified Trombe wall was developed, and the effects of various parameters influencing the heat transfer processes were studied. Full article
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Open AccessArticle
Flow and Fast Fourier Transform Analyses for Tip Clearance Effect in an Operating Kaplan Turbine
Energies 2019, 12(2), 264; https://doi.org/10.3390/en12020264
Received: 16 October 2018 / Revised: 31 December 2018 / Accepted: 9 January 2019 / Published: 16 January 2019
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Abstract
The Kaplan turbine is an axial propeller-type turbine that can simultaneously control guide vanes and runner blades, thus allowing its application in a wide range of operations. Here, turbine tip clearance plays a crucial role in turbine design and operation as high tip [...] Read more.
The Kaplan turbine is an axial propeller-type turbine that can simultaneously control guide vanes and runner blades, thus allowing its application in a wide range of operations. Here, turbine tip clearance plays a crucial role in turbine design and operation as high tip clearance flow can lead to a change in the flow pattern, resulting in a loss of efficiency and finally the breakdown of hydro turbines. This research investigates tip clearance flow characteristics and undertakes a transient fast Fourier transform (FFT) analysis of a Kaplan turbine. In this study, the computational fluid dynamics method was used to investigate the Kaplan turbine performance with tip clearance gaps at different operating conditions. Numerical performance was verified with experimental results. In particular, a parametric study was carried out including the different geometrical parameters such as tip clearance between stationary and rotating chambers. In addition, an FFT analysis was performed by monitoring dynamic pressure fluctuation on the rotor. Here, increases in tip clearance were shown to occur with decreases in efficiency owing to unsteady flow. With this study’s focus on analyzing the flow of the tip clearance and its effect on turbine performance as well as hydraulic efficiency, it aims to improve the understanding on the flow field in a Kaplan turbine. Full article
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Open AccessArticle
Experimental Determination of the Friction Factor in a Tube with Internal Helical Ribs
Energies 2019, 12(2), 257; https://doi.org/10.3390/en12020257
Received: 26 November 2018 / Revised: 10 January 2019 / Accepted: 11 January 2019 / Published: 15 January 2019
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Abstract
Due to the extended geometry of internally rifled tubes with helical ribs, the rate of convective heat transfer within them is much higher compared to smooth tubes. Simultaneously, a rise in the contact surface area between the fluid and the solid body increases [...] Read more.
Due to the extended geometry of internally rifled tubes with helical ribs, the rate of convective heat transfer within them is much higher compared to smooth tubes. Simultaneously, a rise in the contact surface area between the fluid and the solid body increases the friction factor. This paper presents the results of experimental testing performed to determine the friction factor in an internally rifled tube with helical ribs. The tests were carried out on a purpose-built test stand. The tested object was a rifled tube used in the evaporator of a once-through supercritical power boiler operating in a power plant in Poland. The friction factor results obtained from testing are compared to the results of calculations performed by means of correlations known from the literature. Finally, using experimental data, a new correlation is developed that enables the determination of the friction factor in internally rifled tubes with helical ribs. Full article
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Open AccessArticle
Determination of Transient Fluid Temperature and Thermal Stresses in Pressure Thick-Walled Elements Using a New Design Thermometer
Energies 2019, 12(2), 222; https://doi.org/10.3390/en12020222
Received: 16 November 2018 / Revised: 4 January 2019 / Accepted: 7 January 2019 / Published: 11 January 2019
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Abstract
In both conventional and nuclear power plants, the high thermal load of thick-walled elements occurs during start-up and shutdown. Therefore, thermal stresses should be determined on-line during plant start-up to avoid shortening the lifetime of critical pressure elements. It is necessary to know [...] Read more.
In both conventional and nuclear power plants, the high thermal load of thick-walled elements occurs during start-up and shutdown. Therefore, thermal stresses should be determined on-line during plant start-up to avoid shortening the lifetime of critical pressure elements. It is necessary to know the fluid temperature and heat transfer coefficient on the internal surface of the elements, which vary over time to determine transient temperature distribution and thermal stresses in boilers critical pressure elements. For this reason, accurate measurement of transient fluid temperature is very significant, and the correct determination of transient thermal stresses depends to a large extent on it. However, thermometers used in power plants are not able to measure the transient fluid temperature with adequate accuracy due to their massive housing and high thermal inertia. The article aims to present a new technique of measuring transient superheated steam temperature and the results of its application on a real object. Full article
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Open AccessArticle
Linear Optimisation of a Settlement Towards the Energy-Plus House Standard
Energies 2019, 12(2), 210; https://doi.org/10.3390/en12020210
Received: 30 October 2018 / Revised: 21 December 2018 / Accepted: 24 December 2018 / Published: 10 January 2019
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Abstract
Future buildings will use technologies that are either well-known, innovative, or a combination thereof in order to be environmentally friendly and feasible at the same time. To evaluate and compare such systems through simulation, adaptive tools need to be available. This paper describes [...] Read more.
Future buildings will use technologies that are either well-known, innovative, or a combination thereof in order to be environmentally friendly and feasible at the same time. To evaluate and compare such systems through simulation, adaptive tools need to be available. This paper describes a conceived method for planning quarters and settlements. The novelty of this work emerges from the combination of a building simulation with a linear economic optimisation of the energy system, to achieve the energy-plus house standard for a settlement. Furthermore, the tools applied are adaptive or open source. In this article, a hypothetical basic example is given for a predefined idealised settlement, which consists of 132 single-family houses of one building type. The hourly demand for electrical energy and heat is established for three energy-efficiency classes for the building type with a dynamic simulation in MATLAB/SIMULINK using the CARNOT toolbox. This toolbox is also used to calculate the specific electrical energy production by photovoltaics. The components for the energy system of the settlement are implemented in the open source linear optimisation tool URBS. An economic optimum for the energy system of the settlement is found for each of the energy efficiency classes for an accumulated energy demand of the buildings. In this way, a lossless energy hub between the buildings is assumed. The results of the conducted simulations indicate that the optimal ratio of air/water to ground/water heat pumps shifts towards air/water heat pumps with more energy efficient houses. This is due to the lower specific investment costs, which outweigh the operational costs when less energy is required. The lowest costs for the entire energy system are for the one with the most energy efficient settlement. This is the case, as the costs for the higher energy standard of the buildings are not considered in the calculations. The behaviour of the optimisation is tested and discussed through a sensitivity analysis for one efficiency class. By presenting this simple, comprehensible example, an impression of the possible applications for this methodology is conveyed. Full article
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Open AccessArticle
Energetical Analysis of Two Different Configurations of a Liquid-Gas Compressed Energy Storage
Energies 2018, 11(12), 3405; https://doi.org/10.3390/en11123405
Received: 9 November 2018 / Revised: 26 November 2018 / Accepted: 30 November 2018 / Published: 4 December 2018
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Abstract
In order to enhance the spreading of renewable energy sources in the Italian electric power market, as well as to promote self-production and to decrease the phase delay between energy production and consumption, energy storage solutions are catching on. Nowadays, in general, small [...] Read more.
In order to enhance the spreading of renewable energy sources in the Italian electric power market, as well as to promote self-production and to decrease the phase delay between energy production and consumption, energy storage solutions are catching on. Nowadays, in general, small size electric storage batteries represent a quite diffuse technology, while air liquid-compressed energy storage solutions are used for high size. The goal of this paper is the development of a numerical model for small size storage, environmentally sustainable, to exploit the higher efficiency of the liquid pumping to compress air. Two different solutions were analyzed, to improve the system efficiency and to exploit the heat produced by the compression phase of the gas. The study was performed with a numerical model implemented in Matlab, by analyzing the variation of thermodynamical parameters during the compression and the expansion phases, making an energetic assessment for the whole system. The results show a good global efficiency, thus making the system competitive with the smallest size storage batteries. Full article
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Open AccessArticle
Estimation of the Time-Varying High-Intensity Heat Flux for a Two-Layer Hollow Cylinder
Energies 2018, 11(12), 3332; https://doi.org/10.3390/en11123332
Received: 9 October 2018 / Revised: 17 November 2018 / Accepted: 19 November 2018 / Published: 29 November 2018
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Abstract
Gun barrels are subjected to time-varying high-intensity heat flux under multiple firing, which may damage the material and limit the overall performance of the gun. In order to monitor the thermal state of a gun barrel, an inverse method coupling the finite difference [...] Read more.
Gun barrels are subjected to time-varying high-intensity heat flux under multiple firing, which may damage the material and limit the overall performance of the gun. In order to monitor the thermal state of a gun barrel, an inverse method coupling the finite difference method with the sequential function specification method was developed to estimate the unknown time-varying heat flux imposed on the inner wall of a gun barrel. A two-layer hollow cylindrical tube was assumed with the convection heat transfer boundary condition on the outer wall of the tube. A direct heat transfer model was developed, and was used to estimate the temporal distribution of boundary heat flux in approximately real time based on the measured transient temperature at some positions on the outer wall of the gun barrel. Numerical tests were performed to verify the effectiveness and reliability of this method by investigating the influence of temperature measurement noises and future time step selection. The results show that the proposed method has high precision and efficiency in extracting the time-varying heat flux under one-shot and three-shot firing conditions. When there is a measurement noise, this method has good anti-illness characteristics and can achieve better results by appropriately selecting the value of a future time step. Full article
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Open AccessArticle
One-Dimensional Simulation of Synergistic Desulfurization and Denitrification Processes for Electrostatic Precipitators Based on a Fluid-Chemical Reaction Hybrid Model
Energies 2018, 11(12), 3249; https://doi.org/10.3390/en11123249
Received: 28 October 2018 / Revised: 18 November 2018 / Accepted: 19 November 2018 / Published: 22 November 2018
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Abstract
Non-thermal plasma (NTP) technologies can be used to treat a variety of gaseous pollutants, and extensive research has been carried out worldwide because of its high purification efficiency, low dependence on temperature, and other advantages. NO and SO2 are the main gaseous [...] Read more.
Non-thermal plasma (NTP) technologies can be used to treat a variety of gaseous pollutants, and extensive research has been carried out worldwide because of its high purification efficiency, low dependence on temperature, and other advantages. NO and SO2 are the main gaseous pollutants in coal-fired flue gas. The plasma dynamics for desulfurization and denitrification is a hot topic in the field of NTP pollutant control technologies. In this paper, a one-dimensional fluid model for the simultaneous desulfurization and denitrification of flue gas by negative direct current (DC) corona discharge was established based on the traditional zero-dimensional chemical kinetic model. The simplified wire-cylindrical electrodes configuration and numerical simulation conditions are similar to the working process of electrostatic precipitators. The results obtained by the finite element method show that the removal efficiency of NO and SO2 is remarkable in the region with a radius of less than one centimeter around the high-voltage electrode, and the effective purification area expands with the increase of the discharge voltage. There are different removal pathways for NO at different positions in the removal region, while the removal of SO2 is mainly dependent on the oxidation by OH. Full article
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Open AccessArticle
The Use of Direct Carbon Fuel Cells in Compact Energy Systems for the Generation of Electricity, Heat and Cold
Energies 2018, 11(11), 3061; https://doi.org/10.3390/en11113061
Received: 15 October 2018 / Revised: 30 October 2018 / Accepted: 5 November 2018 / Published: 7 November 2018
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Abstract
The study presents a concept and calculations concerning the operation of the direct carbon fuel cell (DCFC) with molten hydroxide electrolyte (MH-DCFC) as the basic source of electricity integrated with heat and cool air generation systems. The technology of direct carbon fuel cells [...] Read more.
The study presents a concept and calculations concerning the operation of the direct carbon fuel cell (DCFC) with molten hydroxide electrolyte (MH-DCFC) as the basic source of electricity integrated with heat and cool air generation systems. The technology of direct carbon fuel cells assumes the direct use of a carbon fuel (such as fossil coal, carbonized biomass, graphite, coke etc.) to generate electricity with high efficiency and low impact on the environment. These cells operate by utilizing carbon fuel in the range of temperatures of 673–973 K and allow for generation of electricity with an efficiency of about 56%. In order to improve the fuel conversion efficiency, the heat generated in the process of cell cooling can be used to prepare hot water, for heating during the heating season, while during the summer period, heat from cooling of the direct carbon fuel cells can be utilized in the process of cool air production (chilled air) using absorption chillers for e.g. air conditioning. This paper presents a case study and simulation calculations of the system composed of MH-DCFC that generates electricity, and runs heat exchangers and an absorption chiller, integrated with the fuel cell to generate heating and cooling for improving the efficiency of the whole system. The maximum heat and cool streams that can be obtained during the operation of the cell were also evaluated. The results obtained in the study can be helpful in the design of autonomous buildings equipped in direct carbon fuel cells as sources of electricity integrated with the systems of heat and cool generation. Full article
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Review

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Open AccessReview
A Performance Evaluation of a Solar Air Heater Using Different Shaped Ribs Mounted on the Absorber Plate—A Review
Energies 2018, 11(11), 3104; https://doi.org/10.3390/en11113104
Received: 14 September 2018 / Revised: 25 October 2018 / Accepted: 25 October 2018 / Published: 9 November 2018
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Abstract
In this paper, the effect of various shapes of ribs used in Solar Air Heaters (SAHs) was discussed. The review is concentrated on the geometry of the rib and its location on the SAH panel. Both numerical and experimental works were considered for [...] Read more.
In this paper, the effect of various shapes of ribs used in Solar Air Heaters (SAHs) was discussed. The review is concentrated on the geometry of the rib and its location on the SAH panel. Both numerical and experimental works were considered for discussion with dry air and Nano fluids as a working fluid. The influence of various shapes, such as an L shape, W shape, V shape, Multiple V shape, V shape with a gap, detachable & attachable ribs etc., was analyzed. The common fact observed from this analysis is that the implementation of artificial roughness in the absorber plate results in a considerable increase in the rate of heat transfer. Further, it is observed that ‘Multiple V-shaped with open between the ribs’ results in the maximum thermal enhancement when compared to the other shapes. Full article
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