Pub Date : 2022-01-16DOI: 10.5772/intechopen.100827
Khadijah K. Lawal, H. Jibril
An unsteady MHD flow of a temperature dependent heat source/sink in an annulus due to ramped motion and ramped temperature of the boundaries has been analyzed. The partial differential equations of the fluid flow are formulated taking into account the ramped temperature and ramped velocity of the inner cylinder. The closed form solution are obtained for three cases of the magnetic field being fixed relative the fluid, cylinder and when the velocity of the magnetic field is less than the velocity of the moving cylinder. The problem is solved using Laplace transform technique to obtain the Laplace domain solution and Riemann sum approximation to obtain the time domain solution. The effect of the governing parameters on the fluid flow are illustrated graphically. It is found that, Hartmann number has a retarding effect on the skin friction at the outer surface of the inner cylinder and mass flow rate. It also decreases fluid velocity for cases K=0.0andK=0.5 the reverse effect is noticed for case K=1.0. Increase in Hartmann number lead to an increase in skin friction at the inner surface of the outer cylinder for case K=0.0 but decreases it for cases K=0.0andK=0.5.
{"title":"Magneto-Hydrodynamic Natural Convection Flow in a Concentric Annulus with Ramped Temperature and Ramped Motion of the Boundaries","authors":"Khadijah K. Lawal, H. Jibril","doi":"10.5772/intechopen.100827","DOIUrl":"https://doi.org/10.5772/intechopen.100827","url":null,"abstract":"An unsteady MHD flow of a temperature dependent heat source/sink in an annulus due to ramped motion and ramped temperature of the boundaries has been analyzed. The partial differential equations of the fluid flow are formulated taking into account the ramped temperature and ramped velocity of the inner cylinder. The closed form solution are obtained for three cases of the magnetic field being fixed relative the fluid, cylinder and when the velocity of the magnetic field is less than the velocity of the moving cylinder. The problem is solved using Laplace transform technique to obtain the Laplace domain solution and Riemann sum approximation to obtain the time domain solution. The effect of the governing parameters on the fluid flow are illustrated graphically. It is found that, Hartmann number has a retarding effect on the skin friction at the outer surface of the inner cylinder and mass flow rate. It also decreases fluid velocity for cases K=0.0andK=0.5 the reverse effect is noticed for case K=1.0. Increase in Hartmann number lead to an increase in skin friction at the inner surface of the outer cylinder for case K=0.0 but decreases it for cases K=0.0andK=0.5.","PeriodicalId":311391,"journal":{"name":"Heat Exchangers [Working Title]","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128876363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-20DOI: 10.5772/intechopen.100450
Shahin Kharaji
A heat exchanger is a unit operation used to transfer heat between two or more fluids at different temperatures. There are many different types of heat exchangers that are categorized based on different criteria, such as construction, flow arrangement, heat transfer mechanism, etc. Heat exchangers are optimized based on their applications. The most common criteria for optimization of heat exchangers are the minimum initial cost, minimum operation cost, maximum effectiveness, minimum pressure drop, minimum heat transfer area, minimum weight, or material. Using the data modeling, the optimization of a heat exchanger can be transformed into a constrained optimization problem and then solved by modern optimization algorithms. In this chapter, the thermal design and optimization of shell and tube heat exchangers are presented.
{"title":"Heat Exchanger Design and Optimization","authors":"Shahin Kharaji","doi":"10.5772/intechopen.100450","DOIUrl":"https://doi.org/10.5772/intechopen.100450","url":null,"abstract":"A heat exchanger is a unit operation used to transfer heat between two or more fluids at different temperatures. There are many different types of heat exchangers that are categorized based on different criteria, such as construction, flow arrangement, heat transfer mechanism, etc. Heat exchangers are optimized based on their applications. The most common criteria for optimization of heat exchangers are the minimum initial cost, minimum operation cost, maximum effectiveness, minimum pressure drop, minimum heat transfer area, minimum weight, or material. Using the data modeling, the optimization of a heat exchanger can be transformed into a constrained optimization problem and then solved by modern optimization algorithms. In this chapter, the thermal design and optimization of shell and tube heat exchangers are presented.","PeriodicalId":311391,"journal":{"name":"Heat Exchangers [Working Title]","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128627251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-11DOI: 10.5772/intechopen.100817
I. Made Arsana, Ruri Agung Wahyuono
The wire and tube heat exchanger has been mostly utilized as a condenser unit in various refrigeration systems. As a class of extended surface-based heat exchanger, not only the operating condition but also the geometry of the wire and tube heat exchanger plays a critical role in determining the overall performance of the heat exchanger. Despite the fact that the current designs that include the inline, single-staggered, and woven matrix-based wire and tube heat exchangers already exhibits positive performance, future design and optimization remain challenging from the thermal and fluids engineering point of view. To guide the optimization strategy in the heat exchanger design, this chapter provides an insight into how the geometrical design impacts the performance of various wire and tube heat exchangers, which can be deduced from either the heat exchanger capacity or efficiency.
{"title":"Design, Performance, and Optimization of the Wire and Tube Heat Exchanger","authors":"I. Made Arsana, Ruri Agung Wahyuono","doi":"10.5772/intechopen.100817","DOIUrl":"https://doi.org/10.5772/intechopen.100817","url":null,"abstract":"The wire and tube heat exchanger has been mostly utilized as a condenser unit in various refrigeration systems. As a class of extended surface-based heat exchanger, not only the operating condition but also the geometry of the wire and tube heat exchanger plays a critical role in determining the overall performance of the heat exchanger. Despite the fact that the current designs that include the inline, single-staggered, and woven matrix-based wire and tube heat exchangers already exhibits positive performance, future design and optimization remain challenging from the thermal and fluids engineering point of view. To guide the optimization strategy in the heat exchanger design, this chapter provides an insight into how the geometrical design impacts the performance of various wire and tube heat exchangers, which can be deduced from either the heat exchanger capacity or efficiency.","PeriodicalId":311391,"journal":{"name":"Heat Exchangers [Working Title]","volume":"299302 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116578766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-03DOI: 10.5772/intechopen.100852
H. Qiu, Yinchuang Yang
In this chapter, we describe surface modification techniques for enhancing heat/mass transfer and evaporation on heated surfaces. The effect of asymmetrical structure in designing a vapor chamber, patterned with multiscale micro/nanostructured surfaces will be introduced. The wettability patterned surface and its mechanism for improving the evaporation rate of a droplet and the thermal performance of nucleate boiling are discussed. An ultrathin vapor chamber based on a wettability patterned evaporator is introduced as a case for the application of the wettability pattern. Besides, modifying the surface with nanostructure to form a multiscale micro/nanostructured surface or superhydrophobic surface also enhances the phase change. Several types of heat spreaders are proposed to investigate the effects of multiscale micro/nanostructured surface and nanostructured superhydrophobic condenser on the thermal performance of the heat spreaders, respectively. The effects of multiscale micro/nanostructured evaporator surfaces with wettability patterns will be analyzed and experimental data will be presented.
{"title":"Multiscale Micro/Nanostructured Heat Spreaders for Thermal Management of Power Electronics","authors":"H. Qiu, Yinchuang Yang","doi":"10.5772/intechopen.100852","DOIUrl":"https://doi.org/10.5772/intechopen.100852","url":null,"abstract":"In this chapter, we describe surface modification techniques for enhancing heat/mass transfer and evaporation on heated surfaces. The effect of asymmetrical structure in designing a vapor chamber, patterned with multiscale micro/nanostructured surfaces will be introduced. The wettability patterned surface and its mechanism for improving the evaporation rate of a droplet and the thermal performance of nucleate boiling are discussed. An ultrathin vapor chamber based on a wettability patterned evaporator is introduced as a case for the application of the wettability pattern. Besides, modifying the surface with nanostructure to form a multiscale micro/nanostructured surface or superhydrophobic surface also enhances the phase change. Several types of heat spreaders are proposed to investigate the effects of multiscale micro/nanostructured surface and nanostructured superhydrophobic condenser on the thermal performance of the heat spreaders, respectively. The effects of multiscale micro/nanostructured evaporator surfaces with wettability patterns will be analyzed and experimental data will be presented.","PeriodicalId":311391,"journal":{"name":"Heat Exchangers [Working Title]","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121271202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-29DOI: 10.5772/intechopen.100024
T. Nhan Phan, Van Hung Tran
Understanding the Heat transfer performance of refrigerant for convective boiling in horizontal microfin tube and smooth tube is place an importance role on the designing of evaporator, the main equipment on refrigeration system. Reviewing the general concept especially the theory of boiling in the tube, the formation of the flow pattern map, the calculating procedure for heat transfer coefficient and pressure drop during boiling process of refrigerant in microfin tube. Besides, a typical example will be presented more detail in step by step to define the heat transfer coefficient and pressure drop for one working condition to estimate the data results without doing experiments.
{"title":"A Review on Convective Boiling Heat Transfer of Refrigerants in Horizontal Microfin-Tubes: A Typical Example","authors":"T. Nhan Phan, Van Hung Tran","doi":"10.5772/intechopen.100024","DOIUrl":"https://doi.org/10.5772/intechopen.100024","url":null,"abstract":"Understanding the Heat transfer performance of refrigerant for convective boiling in horizontal microfin tube and smooth tube is place an importance role on the designing of evaporator, the main equipment on refrigeration system. Reviewing the general concept especially the theory of boiling in the tube, the formation of the flow pattern map, the calculating procedure for heat transfer coefficient and pressure drop during boiling process of refrigerant in microfin tube. Besides, a typical example will be presented more detail in step by step to define the heat transfer coefficient and pressure drop for one working condition to estimate the data results without doing experiments.","PeriodicalId":311391,"journal":{"name":"Heat Exchangers [Working Title]","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128611008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-09-14DOI: 10.5772/intechopen.99736
M. Jamil, Talha S. Goraya, H. Yaqoob, K. Ng, M. Shahzad, S. Zubair
Heat exchangers are the mainstay of thermal systems and have been extensively used in desalination systems, heating, cooling units, power plants, and energy recovery systems. This chapter demonstrates a robust theoretical framework for heat exchangers investigation based on two advanced tools, i.e., exergoeconomic analysis and Normalized Sensitivity Analysis. The former is applied as a mutual application of economic and thermodynamic analyses, which is much more impactful than the conventional thermodynamic and economic analyses. This is because it allows the investigation of combinatory effects of thermodynamic and fiscal parameters which are not achieved with the conventional methods. Similarly, the Normalized Sensitivity Analysis allows a one-on-one comparison of the sensitivity of output parameters to the input parameters with entirely different magnitudes on a common platform. This rationale comparison is obtained by normalizing the sensitivity coefficients by their nominal values, which is not possible with the conventional sensitivity analyses. An experimentally validated example of a plate heat exchanger is used to demonstrate the application of the proposed framework from a desalination system.
{"title":"Exergoeconomic and Normalized Sensitivity Analysis of Plate Heat Exchangers: A Theoretical Framework with Application","authors":"M. Jamil, Talha S. Goraya, H. Yaqoob, K. Ng, M. Shahzad, S. Zubair","doi":"10.5772/intechopen.99736","DOIUrl":"https://doi.org/10.5772/intechopen.99736","url":null,"abstract":"Heat exchangers are the mainstay of thermal systems and have been extensively used in desalination systems, heating, cooling units, power plants, and energy recovery systems. This chapter demonstrates a robust theoretical framework for heat exchangers investigation based on two advanced tools, i.e., exergoeconomic analysis and Normalized Sensitivity Analysis. The former is applied as a mutual application of economic and thermodynamic analyses, which is much more impactful than the conventional thermodynamic and economic analyses. This is because it allows the investigation of combinatory effects of thermodynamic and fiscal parameters which are not achieved with the conventional methods. Similarly, the Normalized Sensitivity Analysis allows a one-on-one comparison of the sensitivity of output parameters to the input parameters with entirely different magnitudes on a common platform. This rationale comparison is obtained by normalizing the sensitivity coefficients by their nominal values, which is not possible with the conventional sensitivity analyses. An experimentally validated example of a plate heat exchanger is used to demonstrate the application of the proposed framework from a desalination system.","PeriodicalId":311391,"journal":{"name":"Heat Exchangers [Working Title]","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129058717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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