Recent developments in applied thermal engineering: Process integration, heat exchangers, enhanced heat transfer, solar thermal energy, combustion and high temperature processes and thermal process modelling

2016 ◽  
Vol 105 ◽  
pp. 755-762 ◽  
Author(s):  
Zhi-Yong Liu ◽  
Petar Sabev Varbanov ◽  
Jiří Jaromír Klemeš ◽  
Jun Yow Yong
Keyword(s):  
Heat Transfer ◽  
Heat Exchangers ◽  
Thermal Process ◽  
Process Integration ◽  
Thermal Engineering ◽  
Engineering Process ◽  
Solar Thermal Energy ◽  
Enhanced Heat Transfer ◽  
High Temperature Processes ◽  
Recent Developments

scholarly journals Diamond-Shaped Extended Fins for Heat Transfer Enhancement in a Double-Pipe Heat Exchanger: An Innovative Design

2021 ◽  
Vol 11 (13) ◽  
pp. 5954
Author(s):  
Muhammad Ishaq ◽  
Amjad Ali ◽  
Muhammad Amjad ◽  
Khalid Saifullah Syed ◽  
Zafar Iqbal
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Enhancement ◽  
Heat Exchangers ◽  
Adaptive Finite Element Method ◽  
Transfer Enhancement ◽  
Enhanced Heat Transfer ◽  
Frictional Loss ◽  
Special Cases ◽  
Double Pipe ◽  
Pipe Heat

Heat transfer enhancement in heat exchangers results in thermal efficiency and energy saving. In double-pipe heat exchangers (DPHEs), extended or augmented fins in the annulus of the two concentric pipes, i.e., at the outer surface of the inner pipe, are used to extend the surface of contact for enhancing heat transfer. In this article, an innovative diamond-shaped design of extended fins is proposed for DPHEs. This type of fin is considered for the first time in the design of DPHEs. The triangular-shaped and rectangular-shaped fin designs of DPHE, available in the literature, can be recovered as special cases of the proposed design. An h-adaptive finite element method is employed for the solution of the governing equations. The results are computed for various performance measures against the emerging parameters. The results dictate that the optimal configurations of the diamond-shaped fins in the DPHE for an enhanced heat transfer are recommended as follows: If around 4–6, 8–12, or 16–32 fins are to be placed in the DPHE, then the height of the fins should be 20%, 80%, or 100%, respectively, of the annulus width. If frictional loss of heat is also to be considered, then for fin-heights of 20–80% and 100% of the annulus width, the placement of 4 and 8 diamond-shaped fins, respectively, is recommended for an enhanced heat transfer. These recommendations are for the radii ratio (i.e., the ratio of the inner pipe radius to that of the outer pipe) of 0.25. The recommendations are be modified if the radii ratio is altered.

Developments in Enhanced Heat Transfer Technology From a Petroleum Industry Perspective in 2012

2012 ◽  
Author(s):  
Matthew P. Rudy ◽  
Thomas M. Rudy ◽  
Himanshu M. Joshi ◽  
Amar S. Wanni
Keyword(s):  
Heat Transfer ◽  
Heat Exchangers ◽  
Petroleum Industry ◽  
Current Paper ◽  
Enhanced Heat Transfer ◽  
The Past

Within the past 30 years, many Enhanced Heat Transfer (EHT) technologies have become available in a number of forms for application in heat exchangers. These technologies are used in various industries to widely different extents. In 1999, H. Joshi, T. Rudy, and A. Wanni, former Ph.D. students of Dr. Ralph L. Webb and specialists in the application of EHTs in the Petroleum Industry prepared a paper for the Journal of Enhanced Heat Transfer that reviewed the extent of use of EHT Technologies in the Petroleum Industry [1]. The current paper reviews how the application of EHT in the Petroleum Industry has changed in the last 14 years.

scholarly journals Performance and Exergy Transfer Analysis of Heat Exchangers with Graphene Nanofluids in Seawater Source Marine Heat Pump System

Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1762 ◽  
Author(s):  
Zhe Wang ◽  
Fenghui Han ◽  
Yulong Ji ◽  
Wenhua Li
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Heat Pump ◽  
Heat Exchangers ◽  
Transfer Model ◽  
Enhanced Heat Transfer ◽  
Pump System ◽  
Heat Pump System ◽  
Tube Heat Exchanger ◽  
Exergy Transfer

A marine seawater source heat pump is based on the relatively stable temperature of seawater, and uses it as the system’s cold and heat source to provide the ship with the necessary cold and heat energy. This technology is one of the important solutions to reduce ship energy consumption. Therefore, in this paper, the heat exchanger in the CO2 heat pump system with graphene nano-fluid refrigerant is experimentally studied, and the influence of related factors on its heat transfer enhancement performance is analyzed. First, the paper describes the transformation of the heat pump system experimental bench, the preparation of six different mass concentrations (0~1 wt.%) of graphene nanofluid and its thermophysical properties. Secondly, this paper defines graphene nanofluids as beneficiary fluids, the heat exchanger gains cold fluid heat exergy increase, and the consumption of hot fluid heat is heat exergy decrease. Based on the heat transfer efficiency and exergy efficiency of the heat exchanger, an exergy transfer model was established for a seawater source of tube heat exchanger. Finally, the article carried out a test of enhanced heat transfer of heat exchangers with different concentrations of graphene nanofluid refrigerants under simulated seawater constant temperature conditions and analyzed the test results using energy and an exergy transfer model. The results show that the enhanced heat transfer effect brought by the low concentration (0~0.1 wt.%) of graphene nanofluid is greater than the effect of its viscosity on the performance and has a good exergy transfer effectiveness. When the concentration of graphene nanofluid is too high, the resistance caused by the increase in viscosity will exceed the enhanced heat transfer gain brought by the nanofluid, which results in a significant decrease in the exergy transfer effectiveness.

scholarly journals Applications of Compound Nanotechnology and Twisted Inserts for Enhanced Heat Transfer

2020 ◽  
Author(s):  
Hussain H. Al-Kayiem ◽  
Muna S. Kassim ◽  
Saud T. Taher
Keyword(s):  
Heat Transfer ◽  
Pressure Drop ◽  
Heat Exchangers ◽  
Volume Fraction ◽  
Twisted Tape ◽  
Enhanced Heat Transfer ◽  
Maximum Increase ◽  
Industrial Plants ◽  
Nanoparticles Volume Fraction ◽  
Double Pipe

Nanoadditives are a type of heat transfer enhancement techniques adopted in heat exchangers to improve the performance of industrial plants through improvement of the thermal properties of base fluids. Recently, various types of inserts with nanofluids are adopted to enhance the thermal performance of double pipe heat exchangers. In the current article, TiO2/water nanofluid with multiple twisted tape inserts was investigated as a hybrid enhancement technique of heat transfer in straight pipes. The investigations were carried out experimentally and numerically at Reynolds numbers varied from 5000 to 20,000. Using nanofluid with 0.1% TiO2 nanoparticles volume fraction demonstrated enhanced heat transfer with slight increase in pressure drop. Results are showing a maximum increase of 110.8% in Nusselt number in a tube fitted with quintuple twisted tape inserts with 25.2% increase in the pressure drop. However, as the article is representing a part of specified book on heat exchangers, the literature has been extended to provide sufficient background to the reader on the use of nanotech, twisted inserts, and hybrid of compound nanofluids and inserts to enhance heat transfer processes.

Comparison of Heat Transfer Performance Between Smooth and Enhanced Heat Transfer Tubes

2019 ◽  
Author(s):  
David J. Kukulka ◽  
Wei Li ◽  
Rick Smith
Keyword(s):  
Heat Transfer ◽  
Heat Exchangers ◽  
High Performance ◽  
Heat Transfer Performance ◽  
Industrial Applications ◽  
Material Surface ◽  
Transfer Performance ◽  
Enhanced Heat Transfer ◽  
Enhanced Tubes ◽  
Smooth Tubes

Abstract Heat transfer enhancement is an important factor in obtaining energy efficiency improvements in all heat transfer applications. A numeric study was performed that compares the performance of heat exchangers using the Vipertex enhanced heat transfer tubes (model 1EHT) to the performance of heat exchangers that use smooth surface tubes and other enhanced tubes. Surface enhancement of the 1EHT tube is accomplished through the use of the primary dimple enhancement and a secondary background pattern made up of petal arrays. Utilization of enhanced heat transfer tubes is an effective method that is utilized in the development of high performance thermal systems. Vipertex™ tubes, have been designed and produced through material surface modifications that produce flow optimized heat transfer tubes that increase heat transfer performance. Current energy demands and the desire to increase efficiencies of systems have prompted the development of optimized enhanced heat transfer surfaces. Enhanced heat transfer tubes are widely used in many areas (refrigeration, air-conditioning, process, petrochemical, chemical, etc.) in order to reduce cost, create a smaller application footprint or increase production. A new type of enhanced heat transfer tube has been created; therefore it is important to investigate relevant heat exchanger designs using the Vipertex enhanced surface tube in industrial applications and compare that performance to smooth tubes and other enhanced tubes. Results include design characteristics and performance predictions using the design simulations produced using HTRI Exchanger Suite (2016). Performance for all cases considered using the Vipertex tube predicted over design when compared to a smooth tube design. Vipertex 1EHT tubes produced enhanced heat transfer and cost efficient designs. In some of the case studies the 1EHT tubes produce an overdesign that is more than 35%, while smooth tubes produce an underdesign and other low fin tubes produce overdesign but not as large as the 1EHT tubes.

Recent developments in enhanced heat transfer

2011 ◽  
Vol 47 (8) ◽  
pp. 1001-1008 ◽  
Author(s):  
Arthur E. Bergles
Keyword(s):  
Heat Transfer ◽  
Enhanced Heat Transfer ◽  
Recent Developments
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