Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
3.4
1.8
Journals
Fluids
Special Issues
Evaporation, Condensation and Heat Transfer
share announcement

Evaporation, Condensation and Heat Transfer

A special issue of Fluids (ISSN 2311-5521). This special issue belongs to the section "Heat and Mass Transfer".

Deadline for manuscript submissions: 31 December 2024 | Viewed by 3121

Special Issue Editors

Dr. Chien-An Chen

E-Mail Website
Guest Editor
Department of Mechanical Engineering, National Yang Ming Chiao Tung University, Hsinchu 30010, Taiwan
Interests: two phase flow heat transfer; system thermal/cooling design; refrigeration and air condition
Dr. Zhao Tian

E-Mail Website
Guest Editor
School of Mechanical Engineering, University of Adelaide, Adelaide, SA 5005, Australia
Interests: computational fluid dynamics (CFD); renewable energy including solar hybrid systems, and geothermal systems; solar cars design/build and simulations; combustion/gasification including fire simulations, coal combustion/gasification, MILD combustion; multiphase flows particularly particle-laden flows

Special Issue Information

Dear Colleagues,

Improvements to the energy utilization efficiency in various engineering systems are receiving ever-increasing worldwide attention in light of their importance in reducing the release of CO2(g), a global weather-warming gas, during the burning of fossil fuels to produce the necessary energy. Recently, the use of variable-frequency, instead of ON/OFF, compressors in various air conditioning and refrigeration systems to meet the temporally changing thermal loads has been found to significantly augment the energy efficiencies of these systems. It is important to note that in these systems, the refrigerant flow rate varies with time, and the systems are subjected to changing thermal loads. How this time-dependent refrigerant flow rate and heat flux affect the characteristics of boiling and condensation processes in the refrigeration cycles employed in these air-conditioning and refrigeration systems remains largely unexplored. In cooling future ultra-high-component density electronic devices, methods based on phase change heat transfer are often considered. Moreover, the power dissipated in these devices is also time-dependent, hence the cooling load. The associated time-dependent two-phase flow and heat transfer processes in electronics cooling are also poorly understood.

Dr. Chien-An Chen
Dr. Zhao Tian
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 submissions that pass pre-check are 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. Fluids is an international peer-reviewed open access monthly 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

  • two-phase flow and heat transfer
  • transient flow boiling
  • flow boiling and evaporation heat transfer
  • time periodic evaporating flow
  • evaporation/evaporative heat transfer
  • flow rate oscillation
  • flow pattern characteristics
  • unsteady heat transfer
  • subcooled flow boiling
  • oscillating refrigerant flow rate
  • triangular oscillation
  • intermittent nucleate boiling
  • amplitude and period
  • energy efficiency
  • saturated flow boiling

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (3 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

23 pages, 7362 KiB  
Article
Thermal Efficiency Analysis of a 1 kW ORC System with a Solar Collection Stage and R-245fa Working Fluid: A Case Study
by Raúl Alejandro Martínez-Sánchez, José M. Álvarez-Alvarado, Gerardo I. Pérez-Soto, Idalberto Macías-Socarrás, Karla A. Camarillo-Gómez and Juvenal Rodríguez-Reséndiz
Fluids 2024, 9(9), 217; https://doi.org/10.3390/fluids9090217 - 15 Sep 2024
Viewed by 701
Abstract
A thermal efficiency analysis of an organic Rankine cycle (ORC) system enables its performance to be evaluated; for this purpose, critical system components, including the turbine and the boiler, must be scrutinized. ORC plants can operate under various regimes, such as simple, regeneration, [...] Read more.
A thermal efficiency analysis of an organic Rankine cycle (ORC) system enables its performance to be evaluated; for this purpose, critical system components, including the turbine and the boiler, must be scrutinized. ORC plants can operate under various regimes, such as simple, regeneration, and reheat work modes. Organic fluids such as R-245fa integrate low-temperature sources such as solar radiation. However, a literature review revealed limited research on the impact of a solar collection system on the overall thermal efficiency of an ORC system during the regeneration stage. In this study, we examined the thermal efficiency behavior of an ORC plant with a 1 kW generator operating in simple and regeneration modes with a solar collection stage. The results show that the thermal efficiency in simple mode was 35.27%, while in regeneration mode with solar collection it reached 51.30%. Improving the thermal efficiency of a thermodynamic cycle system can reduce CO2 emissions. The operating temperature ranges facilitate the development of a methodology for industries to implement ORC systems in their manufacturing processes, thereby utilizing waste heat from industrial operations. Full article
(This article belongs to the Special Issue Evaporation, Condensation and Heat Transfer)
►▼ Show Figures

Figure 1

20 pages, 3682 KiB  
Article
Three-Dimensional Long-Wave Instability of an Evaporation/Condensation Film
by Weiyang Jiang, Ruiqi Huang, Qiang Yang and Zijing Ding
Fluids 2024, 9(6), 143; https://doi.org/10.3390/fluids9060143 - 14 Jun 2024
Viewed by 868
Abstract
This paper explores the stability and dynamics of a three-dimensional evaporating/condensing film while falling down a heated/cooled incline. Instead of using the Hertz–Knudsen–Langmuir relation, a more comprehensive phase-change boundary condition is employed. A nonlinear differential equation is derived based on the Benny-type equation, [...] Read more.
This paper explores the stability and dynamics of a three-dimensional evaporating/condensing film while falling down a heated/cooled incline. Instead of using the Hertz–Knudsen–Langmuir relation, a more comprehensive phase-change boundary condition is employed. A nonlinear differential equation is derived based on the Benny-type equation, which takes into account gravity, energy transport, vapor recoil, effective pressure, and evaporation. The impact of effective pressure and vapor recoil on instability is studied using a linear stability analysis. The results show that spanwise perturbations can amplify the destabilizing effects of vapor recoil, leading to instability. Energy transport along the interface has almost no effect on the stability of the system, but it does influence the linear wave speed. Nonlinear evolution demonstrates that, in contrast to the vapor recoil effect, effective pressure can improve stability and delay film rupture. The self-similar solution demonstrates that the minimal film thickness decreases as (tr−t)1/2 and (tr−t)1/3 under the dominance of evaporation and vapor recoil, respectively. Full article
(This article belongs to the Special Issue Evaporation, Condensation and Heat Transfer)
►▼ Show Figures

Figure 1

13 pages, 5184 KiB  
Article
Circular Fluid Heating—Transient Entropy Generation
by Fikret Alic
Fluids 2024, 9(5), 119; https://doi.org/10.3390/fluids9050119 - 18 May 2024
Viewed by 993
Abstract
A technical issue with fluid flow heating is the relatively small temperature increase as the fluid passes through the heating surface. The fluid does not spend enough time inside the heating source to significantly raise its temperature, despite the heating source itself experiencing [...] Read more.
A technical issue with fluid flow heating is the relatively small temperature increase as the fluid passes through the heating surface. The fluid does not spend enough time inside the heating source to significantly raise its temperature, despite the heating source itself experiencing a substantial increase. To address this challenge, the concept of the multiple circular heating of air was developed, forming the basis of this work. Two PTC heaters with longitudinal fins are located within a closed channel inside housing composed of a thermal insulation material. Air flows circularly from one finned surface to another. Analytical modeling and experimental testing were used in the analysis, with established restrictions and boundary conditions. An important outcome of the analysis was the methodology established for the optimization of the geometric and process parameters based on minimizing the transient thermal entropy. In conducting the analytical modeling, the temperature of the PTC heater was assumed to be constant at 150 °C and 200 °C. By removing the restrictions and adjusting the boundary conditions, the established methodology for the analysis and optimization of various thermally transient industrial processes can be applied more widely. The experimental determination of the transient thermal entropy was performed at a much higher air flow rate of 0.005 m3s−1 inside the closed channel. The minimum transient entropy also indicates the optimal time for the opening of the channel, allowing the heated air to exit. The novelty of this work lies in the controlled circular heating of the fluid and the establishment of the minimum transient thermal entropy as an optimization criterion. Full article
(This article belongs to the Special Issue Evaporation, Condensation and Heat Transfer)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-3
Back to TopTop