Viability of Ceramic High Temperature Heat Exchangers in NGNP Applications

2008 ◽  
Author(s):  
Merrill A. Wilson ◽  
Charles Lewinsohn ◽  
James Cutts ◽  
Yitung Chen ◽  
Valery Ponyavin
Keyword(s):  
High Temperature ◽  
Heat Exchanger ◽  
Heat Exchangers ◽  
Ceramic Materials ◽  
Reliability Models ◽  
Tube Heat Exchanger ◽  
Temperature Heat ◽  
Intermediate Heat Exchanger ◽  
Recent Developments ◽  
Higher Temperature

The recent developments in the energy industry have kindled renewed interest in producing energy more efficiently. This has motivated the development of higher temperature cycles and their associated equipment. In this paper we will discuss several design configurations coupled with the inherent properties of preferred ceramic materials to assess the viability and design reliability of ceramic heat exchangers for next generation high temperature heat exchangers. These analyses have been extended to conceptually compare the traditional shell and tube heat exchanger with shell and plate heat exchangers. These analyses include hydrodynamic, heat transfer, mechanical stress and reliability models applicable to an Intermediate Heat Exchanger (IHX) and Process Coupling Heat Exchangers. It was found that ceramic micro-channel heat exchanger designs proved to have the greatest reliability due to their inherent mechanical properties, minimal thermo-mechanical stresses while improving the performance efficiency in a compact footprint.

Design Considerations for High Temperature, Ceramic Heat Exchangers

2007 ◽  
Author(s):  
Merrill A. Wilson ◽  
Charles Lewinsohn ◽  
James Cutts
Keyword(s):  
High Temperature ◽  
Heat Exchanger ◽  
Heat Exchangers ◽  
Alternative Fuels ◽  
Ceramic Materials ◽  
Reliability Models ◽  
Tube Heat Exchanger ◽  
Recent Developments ◽  
Higher Temperature ◽  
Shell And Tube

The recent developments in the energy industry have kindled renewed interest in producing energy (alternative fuels and electricity) more efficiently. This has motivated the development of higher temperature cycles and their associated equipment. In this paper we will discuss several design configurations coupled with the inherent properties of preferred ceramic materials to assess the viability and design reliability of ceramic heat exchangers for next generation high temperature heat exchangers. These analyses have been extended to conceptually compare the traditional shell and tube heat exchanger with shell and plate heat exchangers. These analyses include hydrodynamic, heat transfer, mechanical stress and reliability models. It was found that ceramic micro-channel heat exchanger designs proved to have the greatest reliability due to their inherent mechanical properties, minimal thermo-mechanical stresses while improving the performance efficiency in a compact footprint.

Performance Optimization of Compact Ceramic High Temperature Heat Exchangers

2007 ◽  
Author(s):  
Q. Y. Chen ◽  
M. Zeng ◽  
D. H. Zhang ◽  
Q. W. Wang
Keyword(s):  
Heat Transfer ◽  
High Temperature ◽  
Heat Exchanger ◽  
Performance Optimization ◽  
Heat Exchangers ◽  
Radiation Heat Transfer ◽  
Surface Radiation ◽  
Radiation Heat ◽  
High Temperature Side ◽  
Temperature Heat

In the present paper, the compact ceramic high temperature heat exchangers with parallel offset strip fins and inclined strip fins (inclined angle β = 0∼70°) are investigated with CFD method. The numerical simulations are carried out for high temperature (1500°C), without and with radiation heat transfer, and the periodic boundary is used in transverse direction. The fluid of high temperature side is the standard flue gas. The material of heat exchanger is SiC. NuS-G.R(with surface and gaseous radiation heat transfer) is averagely higher than NuNo.R (without radiation heat transfer) by 7% and fS-G.R is averagely higher than fNo.R by 5%. NuS-G.R(with surface and gaseous radiation heat transfer) is averagely higher than NuS.R (with only surface radiation heat transfer) by 0.8% and fS-G.R is averagely higher than fS.R by 3%. The thermal properties have significantly influence on the heat transfer and pressure drop characteristics, respectively. The heat transfer performance of the ceramic heat exchanger with inclined fins (β = 30°) is the best.

Flow Distribution on the Tube Side of a High Temperature Heat Exchanger and Chemical Decomposer

2007 ◽  
Author(s):  
Gayatri Kuchi ◽  
Valery Ponyavin ◽  
Yitung Chen ◽  
Steven Sherman ◽  
Anthony E. Hechanova
Keyword(s):  
High Temperature ◽  
Heat Exchanger ◽  
Flow Distribution ◽  
Straight Tube ◽  
Baffle Plate ◽  
Pumping Power ◽  
Tube Heat Exchanger ◽  
Temperature Heat ◽  
Shell And Tube ◽  
Flow Maldistribution

Numerical simulations of a high temperature shell and tube heat exchanger and chemical decomposer (thereafter — heat exchanger) with straight tube configuration have been performed using Fluent 6.2.16 code to examine flow distribution on the tube side. The heat exchanger can be a part of sulfur iodine thermochemical water splitting cycle which is one of the most studied cycles for hydrogen production. Uniformity of the flow distribution in the heat exchanger is very critical because the flow maldistribution among the tube or shell sides can result in decreasing of chemical decomposition and increasing of pumping power. In the current study the flow rate uniformity in the heat exchanger tubes has been investigated. Simulations of the straight tube configuration, tube configuration with baffle plate arrangement and with pebble bed region inside the tubes were performed to examine flow distribution on the tube side. It was found the flow maldistribution along the tube direction is very serious with the simple tube configuration. An improvement of the header configuration has been done by introducing a baffle plate in to the header section. With the introduction of the baffle plate, there was a noticeable decrease in the flow maldistribution in the tubes. Uniformity of flow was also investigated with catalytic bed inside the tubes. A significant decrease in flow maldistribution was observed with this arrangement. But if the catalytic bed zone is created on the shell side, then the improved header configuration with a baffle plate is best suitable to avoid flow maldistribution.

scholarly journals RECENT DEVELOPMENTS IN HIGH TEMPERATURE HEAT EXCHANGERS: A REVIEW

2018 ◽  
Vol 11 ◽  
Author(s):  
Michael Ohadi ◽  
Xiang Zhang ◽  
Hadi Keramati ◽  
Martinus Arie ◽  
Farah Singer ◽  
...  
Keyword(s):  
High Temperature ◽  
Heat Exchangers ◽  
Temperature Heat ◽  
Recent Developments

Design and Development of a Low-Cost, High Temperature Silicon Carbide Micro-Channel Recuperator

2005 ◽  
Author(s):  
Merrill A. Wilson ◽  
Kurt Recknagle ◽  
Kriston Brooks
Keyword(s):  
Heat Transfer ◽  
Silicon Carbide ◽  
High Temperature ◽  
Heat Exchanger ◽  
Thermal Efficiency ◽  
Heat Exchangers ◽  
Ceramic Materials ◽  
Micro Channel ◽  
Micro Channels ◽  
Micro Turbine

Typically, ceramic micro-channel devices are used for high temperature heat exchangers, catalytic reactors, electronics cooling, and processing of corrosive streams where the thermomechanical benefits of ceramic materials are desired. These benefits include: high temperature mechanical and corrosion properties and tailorable material properties such as thermal expansion, electrical conductivity and thermal conductivity. In addition, by utilizing Laminated Object Manufacturing (LOM) methods, inexpensive ceramic materials can be layered, featured and laminated in the green state and co-sintered to form monolithic structures amenable to mass production. In cooperation with the DOE and Pacific Northwest National Labs, silicon carbide (SiC) based micro-channel recuperator concepts are being developed and tested. The performance benefits of a high temperature, micro-channel heat exchanger are realized from the improved thermal efficiency of the high temperature cycles and the improved effectiveness of micro-channels for heat transfer. In designing these structures, the heat and mass transfer within the micro-channels are being analyzed with heat transfer models, computational fluid dynamics models and validated with experimental results. As an example, a typical micro-turbine cycle was modified and modeled to incorporate this ceramic recuperator and it was found that the overall thermal efficiency of the micro-turbine could be improved from about 27% to over 40%. Process improvements require technical advantages and cost advantages. These LOM methodologies have been based on well-proven industry standard processes where labor, throughput and capital estimates have been tested. Following these cost models and validation at the prototype scale, cost estimates were obtained. For the micro-turbine example, cost estimates indicate that the high-temperature SiC recuperator would cost about $200 per kWe. The development of these heat exchangers is multi-faceted and this paper focuses on the design optimization of a layered micro-channel heat exchanger, its performance testing, and fabrication development through LOM methodologies.

High Temperature Heat Exchangers (HTHX) for Nuclear Applications

2006 ◽  
Author(s):  
James C. Govern ◽  
Cila V. Herman ◽  
Dennis C. Nagle
Keyword(s):  
High Temperature ◽  
Heat Exchanger ◽  
Heat Exchangers ◽  
Operating Conditions ◽  
Heat Exchanger Design ◽  
Performance Requirements ◽  
Starting Point ◽  
Temperature Heat ◽  
And Performance ◽  
Design Challenges

Many nuclear engineering applications, current and future, require heat exchangers operating at high temperatures. The operating conditions and performance requirements of these heat exchangers present special design challenges. This paper considers these challenges with respect to a simple heat exchanger design manufactured of a novel carbon material. Heat transfer and effectiveness calculations are performed for several parametric studies regarding heat exchanger parameters. These results are used to better understand the design challenges of high temperature heat exchangers as well as provide a starting point for future optimization work on more complex heat exchanger designs.

scholarly journals Thermal performance measurement of additive manufactured high-temperature compact heat exchangers

2021 ◽  
Vol 2116 (1) ◽  
pp. 012095
Author(s):  
M. Fuchs ◽  
D. Heinrich ◽  
X. Luo ◽  
S. Kabelac
Keyword(s):  
High Temperature ◽  
Heat Exchanger ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Thermal Performance ◽  
Heat Exchangers ◽  
Fluid Temperature ◽  
Test Rig ◽  
Temperature Heat

Abstract Due to increased distribution of high-temperature processes in energy and process plants, more efficient and compact high-temperature heat exchangers are being developed. The additive manufacturing allows the construction of compact sizes and application-specific requirements. To evaluate the thermal performance of these heat exchangers, experimental investigations are evident. This study presents a test rig for testing compact high-temperature heat exchangers as well as a first set of thermal performance data of an additively manufactured plate-fin heat exchanger. The test rig can provide a maximum fluid temperature of 900°C and a maximum mass flow rate of 0.8 kg/min. A steam unit can add steam to the fluid stream to evaluate the influence of gas radiation on the thermal performance. The capabilities of this test rig are being tested with the plate-fin heat exchanger, varying the mass flow rate between 0.2 - 0.52 kg/min at a hot and cold inlet temperature of 750°C and 250°C. The overall effectiveness of the heat exchanger is approx. 0.9.

scholarly journals Comprehensive analysis of transfer processes in modern high-temperature heat exchangers

2019 ◽  
Vol 41 (3) ◽  
pp. 26-32
Author(s):  
B. Soroka ◽  
V. Zgurskyi
Keyword(s):  
Heat Transfer ◽  
High Temperature ◽  
Heat Exchangers ◽  
Exchange Process ◽  
Comprehensive Analysis ◽  
Cfd Modeling ◽  
Tube Heat Exchanger ◽  
Transfer Processes ◽  
Temperature Heat ◽  
Heat Exchange Process

The CFD modeling of high-temperature tube heat exchanger has been carried out. The results of numerical analysis of internal and external secondary emitters’ (SEE) influence upon intensity and uniformity of resulting heat transfer have been presented and discussed. An internal SEE have the determining impact upon heat exchange process thus enhancing the resulting heat flux till extra 40%.

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