The objective of the present study is to determine the thermophysical properties (thermal conductivity, volumetric heat capacity, thermal diffusivity, and thermal effusivity) of concrete manufactured using two different sizes of coarse aggregates by mixing ratios of 1:1.5:3 for application in building construction. The thermal conductivity and the volumetric heat capacity of these samples were measured experimentally in the dry state at ambient temperature (20°C), and at 28 days of age using a CT-meter. Comparative studies were carried out on the compaction effect of normal concrete with two different types of coarse aggregates G1 and G2. The effect of compaction rate and the bulk density on thermal properties was analyzed. The findings of the study indicate that the size of coarse aggregates along with compaction have an influence on the thermal properties of the tested concretes, which demonstrate a notable improvement with increase in compaction. Received: June 3, 2023Accepted: July 21, 2023
{"title":"EFFECT OF AGGREGATE TYPES AND COMPACTION RATE ON THE THERMOPHYSICAL PROPERTIES OF NORMAL CONCRETE","authors":"Kanibou Fatima","doi":"10.17654/0973576323044","DOIUrl":"https://doi.org/10.17654/0973576323044","url":null,"abstract":"The objective of the present study is to determine the thermophysical properties (thermal conductivity, volumetric heat capacity, thermal diffusivity, and thermal effusivity) of concrete manufactured using two different sizes of coarse aggregates by mixing ratios of 1:1.5:3 for application in building construction. The thermal conductivity and the volumetric heat capacity of these samples were measured experimentally in the dry state at ambient temperature (20°C), and at 28 days of age using a CT-meter. Comparative studies were carried out on the compaction effect of normal concrete with two different types of coarse aggregates G1 and G2. The effect of compaction rate and the bulk density on thermal properties was analyzed. The findings of the study indicate that the size of coarse aggregates along with compaction have an influence on the thermal properties of the tested concretes, which demonstrate a notable improvement with increase in compaction. Received: June 3, 2023Accepted: July 21, 2023","PeriodicalId":39006,"journal":{"name":"JP Journal of Heat and Mass Transfer","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135437075","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}
The aim of this work is to study the thermo-physical parameters of a mixture based on concrete and polyethylene terephthalate (PET). The two materials are mixed in a defined mass ratio to produce a new material, whose thermo-physical parameters (thermal conductivity, thermal capacity) are determined using a CT-meter apparatus [1].The measuring cell is a temperature-controlled glove box. The experimental results show an improvement of the thermal performance while adding plastic waste. The conductivity and the thermal capacity of the composite decrease as a result of the addition of recycled plastic. Received: June 16, 2023Accepted: July 20, 2023
{"title":"THERMO-PHYSICAL CHARACTERIZATION OF CONCRETE AND PET MIXTURES","authors":"H. Soulami, A. Samaouali","doi":"10.17654/0973576323041","DOIUrl":"https://doi.org/10.17654/0973576323041","url":null,"abstract":"The aim of this work is to study the thermo-physical parameters of a mixture based on concrete and polyethylene terephthalate (PET). The two materials are mixed in a defined mass ratio to produce a new material, whose thermo-physical parameters (thermal conductivity, thermal capacity) are determined using a CT-meter apparatus [1].The measuring cell is a temperature-controlled glove box. The experimental results show an improvement of the thermal performance while adding plastic waste. The conductivity and the thermal capacity of the composite decrease as a result of the addition of recycled plastic. Received: June 16, 2023Accepted: July 20, 2023","PeriodicalId":39006,"journal":{"name":"JP Journal of Heat and Mass Transfer","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135437065","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}
N. K. Enagi, Krishna B. Chavaraddi, Sridhar Kulkarni
The effect of internal heat generation and density maximum on the onset of convection in a couple-stress fluid saturated rotating porous layer is studied analytically, when porous medium is not in local thermal equilibrium (LTNE). Two-field model is used for the energy equations each representing the solid and fluid phases separately. The linear stability theory is based on normal mode technique. Galerkin method is used to find the eigen values of the problem. The effects of internal generation, rotation and conductivity ratio are determined. Received: March 12, 2023Accepted: July 4, 2023
{"title":"COUPLE-STRESS FLUID SATURATED ROTATING POROUS LAYER WITH INTERNAL HEAT GENERATION AND DENSITY MAXIMUM","authors":"N. K. Enagi, Krishna B. Chavaraddi, Sridhar Kulkarni","doi":"10.17654/0973576323039","DOIUrl":"https://doi.org/10.17654/0973576323039","url":null,"abstract":"The effect of internal heat generation and density maximum on the onset of convection in a couple-stress fluid saturated rotating porous layer is studied analytically, when porous medium is not in local thermal equilibrium (LTNE). Two-field model is used for the energy equations each representing the solid and fluid phases separately. The linear stability theory is based on normal mode technique. Galerkin method is used to find the eigen values of the problem. The effects of internal generation, rotation and conductivity ratio are determined. Received: March 12, 2023Accepted: July 4, 2023","PeriodicalId":39006,"journal":{"name":"JP Journal of Heat and Mass Transfer","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135437072","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}
We investigate the thermoelastic stress generation and temperature distribution in a thin circular plate using the integral transform method. The initial temperature distribution in the plate follows a parabolic profile along the $z$-axis, with insulation at $z=0$ and $z=h$. The surface $r=a$ of the circular plate is subjected to thermal heat transfer at different temperatures, followed by convection with a fluid at temperature $T_{infty}$ and a convection coefficient $h_c$. The analytical solution for thermal stress, displacement, and temperature is derived using the integral transform method and implemented using PTC Mathcad software. Received: June 16, 2023Revised: August 8, 2023 Accepted: August 14, 2023
{"title":"FRACTIONAL ORDER THERMOELASTIC PROBLEM FOR A THIN CIRCULAR PLATE WITH UNIFORM INTERNAL HEAT GENERATION","authors":"Narsing B. Jadhav","doi":"10.17654/0973576323045","DOIUrl":"https://doi.org/10.17654/0973576323045","url":null,"abstract":"We investigate the thermoelastic stress generation and temperature distribution in a thin circular plate using the integral transform method. The initial temperature distribution in the plate follows a parabolic profile along the $z$-axis, with insulation at $z=0$ and $z=h$. The surface $r=a$ of the circular plate is subjected to thermal heat transfer at different temperatures, followed by convection with a fluid at temperature $T_{infty}$ and a convection coefficient $h_c$. The analytical solution for thermal stress, displacement, and temperature is derived using the integral transform method and implemented using PTC Mathcad software. Received: June 16, 2023Revised: August 8, 2023 Accepted: August 14, 2023","PeriodicalId":39006,"journal":{"name":"JP Journal of Heat and Mass Transfer","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135437074","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}
This paper is concerned with the melting of a horizontal ice plate from below. The bottom hot plate is fixed at the temperature $T_h$ higher than $5^{circ} mathrm{C}$ and lower than $25^{circ} mathrm{C}$ and an initial ice temperature $T_{i n i}$ is the melting point $left(0^{circ} mathrm{C}right)$. The ice plate melts after the onset of natural convection based on the maximum density at $4^{circ} mathrm{C}$. The average heat transfer coefficient $alpha_{a v}$ in the melting by natural convection is obtained by means of the numerical calculations on the PHOENICS Code. Melt thickness $X$ can be predicted by the Neumann's solution in the beginning of the melting. After the natural convection appeared, the transient melt thickness is predicted approximately by a simple closed form analytical solution including optimal average heat transfer coefficient $alpha_{a v}$ determined by the numerical solutions. The average heat transfer coefficient in the range of $T_h>25^{circ} mathrm{C}$ can be estimated by the experimental results of the Nusselt number $(mathrm{Nu})$ and the Rayleigh number $(R a)$ in the common liquids without the maximum density. Received: March 6, 2023Revised: July 27, 2023Accepted: August 2, 2023
{"title":"MELTING FROM BELOW OF A HORIZONTAL ICE PLATE IN A RECTANGULAR CAVITY","authors":"M. Sugawara, M. Tago","doi":"10.17654/0973576323040","DOIUrl":"https://doi.org/10.17654/0973576323040","url":null,"abstract":"This paper is concerned with the melting of a horizontal ice plate from below. The bottom hot plate is fixed at the temperature $T_h$ higher than $5^{circ} mathrm{C}$ and lower than $25^{circ} mathrm{C}$ and an initial ice temperature $T_{i n i}$ is the melting point $left(0^{circ} mathrm{C}right)$. The ice plate melts after the onset of natural convection based on the maximum density at $4^{circ} mathrm{C}$. The average heat transfer coefficient $alpha_{a v}$ in the melting by natural convection is obtained by means of the numerical calculations on the PHOENICS Code. Melt thickness $X$ can be predicted by the Neumann's solution in the beginning of the melting. After the natural convection appeared, the transient melt thickness is predicted approximately by a simple closed form analytical solution including optimal average heat transfer coefficient $alpha_{a v}$ determined by the numerical solutions. The average heat transfer coefficient in the range of $T_h>25^{circ} mathrm{C}$ can be estimated by the experimental results of the Nusselt number $(mathrm{Nu})$ and the Rayleigh number $(R a)$ in the common liquids without the maximum density. Received: March 6, 2023Revised: July 27, 2023Accepted: August 2, 2023","PeriodicalId":39006,"journal":{"name":"JP Journal of Heat and Mass Transfer","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135437069","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}
The objective of this work is to determine the variation of thermal properties (thermal conductivity, volumetric heat capacity, thermal diffusivity and thermal effusivity) of red earth blocks, according to the compaction rates at different degrees of temperatures (20°C, 30°C, 40°C and 50°C). Several red earth samples were compacted with different centrifugal weights (250g, 500g and 1000g). Using the CT-meter, we measure the thermal properties of these samples experimentally in the dry state at different temperatures. The experimental results obtained show a significant increase in these thermal properties with the increase in compaction rate. However, as temperature increases, the thermal properties decrease for the samples studied. Received: July 5, 2023Revised: August 15, 2023Accepted: August 25, 2023
{"title":"THE INFLUENCE OF COMPACTION AND TEMPERATURE ON THE THERMAL PROPERTIES OF COMPOSITE CLAY MATERIALS","authors":"Karima Ouaazizi, Abderrahim Samaouali","doi":"10.17654/0973576323047","DOIUrl":"https://doi.org/10.17654/0973576323047","url":null,"abstract":"The objective of this work is to determine the variation of thermal properties (thermal conductivity, volumetric heat capacity, thermal diffusivity and thermal effusivity) of red earth blocks, according to the compaction rates at different degrees of temperatures (20°C, 30°C, 40°C and 50°C). Several red earth samples were compacted with different centrifugal weights (250g, 500g and 1000g). Using the CT-meter, we measure the thermal properties of these samples experimentally in the dry state at different temperatures. The experimental results obtained show a significant increase in these thermal properties with the increase in compaction rate. However, as temperature increases, the thermal properties decrease for the samples studied. Received: July 5, 2023Revised: August 15, 2023Accepted: August 25, 2023","PeriodicalId":39006,"journal":{"name":"JP Journal of Heat and Mass Transfer","volume":"138 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135437249","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}
S. Dilip Jose, K. Selvaraj, P. N. Sudha, P. Geetha, D. Lakshmikaanth
The investigation focuses on the unstable parabolic flow of an electrically driven fluid past an impermeable, unbounded, isothermal, perpendicular plate in the presence of a first-order chemical reaction and Hall current. The Laplace method, which transforms time-domain differential equations into frequency-domain differential equations, is used to solve the governing equations. We have covered the graphical interpretation of concentration, velocity, and temperature profiles for several physical criteria such as the Prandtl number, the thermal Grashof number, the mass Grashof number, the Schmidt number, the Hartmann number, and the skin friction. The accuracy of estimating the velocity increase resulting from a chemical reaction is improved by taking into account Grashof numbers (Gr and Gc), Hall current (h), and their interactions. It is also clear that the velocity decreases as the Hartmann, Schmidt, and Prandtl numbers increase. These findings are crucial for understanding the dynamics of fluid flow and chemical reactions in various industrial processes, such as metallurgy, electroplating, and material processing. They can also inform the design of more efficient and effective systems for these applications. Received: April 15, 2023Revised: June 7, 2023Accepted: July 4, 2023
{"title":"HEAT AND MASS TRANSFER EFFECTS ON PARABOLIC FLOW PAST AN ACCELERATED ISOTHERMAL VERTICAL PLATE IN THE PRESENCE OF CHEMICAL REACTION AND HALL CURRENT","authors":"S. Dilip Jose, K. Selvaraj, P. N. Sudha, P. Geetha, D. Lakshmikaanth","doi":"10.17654/0973576323042","DOIUrl":"https://doi.org/10.17654/0973576323042","url":null,"abstract":"The investigation focuses on the unstable parabolic flow of an electrically driven fluid past an impermeable, unbounded, isothermal, perpendicular plate in the presence of a first-order chemical reaction and Hall current. The Laplace method, which transforms time-domain differential equations into frequency-domain differential equations, is used to solve the governing equations. We have covered the graphical interpretation of concentration, velocity, and temperature profiles for several physical criteria such as the Prandtl number, the thermal Grashof number, the mass Grashof number, the Schmidt number, the Hartmann number, and the skin friction. The accuracy of estimating the velocity increase resulting from a chemical reaction is improved by taking into account Grashof numbers (Gr and Gc), Hall current (h), and their interactions. It is also clear that the velocity decreases as the Hartmann, Schmidt, and Prandtl numbers increase. These findings are crucial for understanding the dynamics of fluid flow and chemical reactions in various industrial processes, such as metallurgy, electroplating, and material processing. They can also inform the design of more efficient and effective systems for these applications. Received: April 15, 2023Revised: June 7, 2023Accepted: July 4, 2023","PeriodicalId":39006,"journal":{"name":"JP Journal of Heat and Mass Transfer","volume":"206 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135437060","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}
Passive heat transfer augmentation techniques play a crucial role in enhancing the performance and efficiency of various thermal systems. This paper presents a comprehensive review of the state-of-the-art of passive heat transfer augmentation techniques, highlighting their principles, and thermo-hydraulic performance characteristics. The first part of the paper provides an overview of the fundamental principles underlying passive heat transfer augmentation. The discussion then delves into the concept of passive techniques, which rely on the intrinsic properties of the working fluids and the geometrical configurations to enhance heat transfer without the need for external energy input. The paper subsequently reviews a wide range of passive heat transfer augmentation techniques. It covers techniques such as surface modifications, including roughening, surface coatings, and porous media, which enhance convective heat transfer by altering the boundary layer characteristics. Furthermore, the paper explores the utilization of passive inserts, such as vortex generators, baffles, and turbulators, to induce fluid mixing and disrupt laminar flow, thereby increasing the convective heat transfer coefficient. Overall, this comprehensive review serves as a valuable resource for researchers, engineers, and practitioners interested in understanding and applying passive heat transfer augmentation techniques. It provides insights into the underlying principles and performance characteristics of these techniques, fostering further advancements in the field of thermal engineering. Received: April 29, 2023Revised: July 5, 2023Accepted: September 7, 2023
{"title":"A COMPREHENSIVE REVIEW ON PASSIVE HEAT TRANSFER AUGMENTATION TECHNIQUES FOR PIPE HEAT EXCHANGERS","authors":"A. A. Kapse","doi":"10.17654/0973576323048","DOIUrl":"https://doi.org/10.17654/0973576323048","url":null,"abstract":"Passive heat transfer augmentation techniques play a crucial role in enhancing the performance and efficiency of various thermal systems. This paper presents a comprehensive review of the state-of-the-art of passive heat transfer augmentation techniques, highlighting their principles, and thermo-hydraulic performance characteristics. The first part of the paper provides an overview of the fundamental principles underlying passive heat transfer augmentation. The discussion then delves into the concept of passive techniques, which rely on the intrinsic properties of the working fluids and the geometrical configurations to enhance heat transfer without the need for external energy input. The paper subsequently reviews a wide range of passive heat transfer augmentation techniques. It covers techniques such as surface modifications, including roughening, surface coatings, and porous media, which enhance convective heat transfer by altering the boundary layer characteristics. Furthermore, the paper explores the utilization of passive inserts, such as vortex generators, baffles, and turbulators, to induce fluid mixing and disrupt laminar flow, thereby increasing the convective heat transfer coefficient. Overall, this comprehensive review serves as a valuable resource for researchers, engineers, and practitioners interested in understanding and applying passive heat transfer augmentation techniques. It provides insights into the underlying principles and performance characteristics of these techniques, fostering further advancements in the field of thermal engineering. Received: April 29, 2023Revised: July 5, 2023Accepted: September 7, 2023","PeriodicalId":39006,"journal":{"name":"JP Journal of Heat and Mass Transfer","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135437250","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}
E. Turzo-Andras, N. Arifovic, D. Sestan, D. Zvizdić, S. Čohodarević, N. Mutapčić, S. Spasova, K. Aldev, S. Nedialkov, C. Stratulat, R. Strnad, L. Knazovicka, G. Buzuc, T. Vukićević
{"title":"DETERMINATION OF THERMOCOUPLE INHOMOGENEITY USING MINIATURE CURIE-POINT FURNACE","authors":"E. Turzo-Andras, N. Arifovic, D. Sestan, D. Zvizdić, S. Čohodarević, N. Mutapčić, S. Spasova, K. Aldev, S. Nedialkov, C. Stratulat, R. Strnad, L. Knazovicka, G. Buzuc, T. Vukićević","doi":"10.17654/0973576323034","DOIUrl":"https://doi.org/10.17654/0973576323034","url":null,"abstract":"","PeriodicalId":39006,"journal":{"name":"JP Journal of Heat and Mass Transfer","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43217382","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}
A. Elshabrawy, Sayed Ahmed, Mohamed A. Abdelatief, Essam H Ibrahim, M. Adel
Extended fins play a vital role in enhancing the thermal performance
延长翅片在提高热性能方面起着至关重要的作用
{"title":"THERMAL ANALYSIS OF A TWO-PHASE CLOSED THERMOSYPHON WITH INTERNAL SEMI-CYLINDRICAL FINNED CONDENSER: AN EXPERIMENTAL STUDY","authors":"A. Elshabrawy, Sayed Ahmed, Mohamed A. Abdelatief, Essam H Ibrahim, M. Adel","doi":"10.17654/0973576323031","DOIUrl":"https://doi.org/10.17654/0973576323031","url":null,"abstract":"Extended fins play a vital role in enhancing the thermal performance","PeriodicalId":39006,"journal":{"name":"JP Journal of Heat and Mass Transfer","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41492845","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：