Pub Date : 2023-11-13DOI: 10.30684/etj.2023.141453.1498
Muthna Fadhil, Sadik Gharghan, Thamir Saeed
One of the biggest threats to human health is air pollution, which significantly influences people. Due to challenges like industrial and rural locations, where sensing frequently falls short of providing sufficient information about air quality, it is challenging to collect data close to pollution sources. Government-led statically deployed stationary monitors are typically used for air quality monitoring. However, many emissions that contribute to air pollution are erratic and unpredictable. A significant problem for environmental protection will be how to monitor air pollution emissions dynamically and efficiently. It can fulfill two objectives. The first is that if the Unmanned Aerial Vehicle (UAV) is flying to a remotely monitored target, it can relay the detected data back to the server in real-time. This work aims to suggest an innovative mobile wireless air pollution monitoring system comprising UAVs with inexpensive air pollution sensors that transmit data over Long Range (LoRa). The outcomes also demonstrated that LoRa Radio transmitter sx1278 could transmit data for distances up to 5km in urban areas. The system was tested successfully at two sites in the Ewairij industrial area south of Baghdad, and the data was received at the base station from the sensor Node, which is carried by the drone during its flight for a distance of 1.5 km and height of 20 meters, round trip. As a result, the industrial areas were classified according to the Air Quality Index (AQI) between satisfactory to moderate according to gas concentrations. The highest gas carbon monoxide (CO) concentration increase was close to dangerous in both sites, as it recorded 9.75µg/m3 in site#1 and 7.75µg/m3 in site#2. In conclusion, the AQI did not reach a poor level in these tested areas.
{"title":"LoRa Sensor Node Mounted on Drone for Monitoring Industrial Area Gas Pollution","authors":"Muthna Fadhil, Sadik Gharghan, Thamir Saeed","doi":"10.30684/etj.2023.141453.1498","DOIUrl":"https://doi.org/10.30684/etj.2023.141453.1498","url":null,"abstract":"One of the biggest threats to human health is air pollution, which significantly influences people. Due to challenges like industrial and rural locations, where sensing frequently falls short of providing sufficient information about air quality, it is challenging to collect data close to pollution sources. Government-led statically deployed stationary monitors are typically used for air quality monitoring. However, many emissions that contribute to air pollution are erratic and unpredictable. A significant problem for environmental protection will be how to monitor air pollution emissions dynamically and efficiently. It can fulfill two objectives. The first is that if the Unmanned Aerial Vehicle (UAV) is flying to a remotely monitored target, it can relay the detected data back to the server in real-time. This work aims to suggest an innovative mobile wireless air pollution monitoring system comprising UAVs with inexpensive air pollution sensors that transmit data over Long Range (LoRa). The outcomes also demonstrated that LoRa Radio transmitter sx1278 could transmit data for distances up to 5km in urban areas. The system was tested successfully at two sites in the Ewairij industrial area south of Baghdad, and the data was received at the base station from the sensor Node, which is carried by the drone during its flight for a distance of 1.5 km and height of 20 meters, round trip. As a result, the industrial areas were classified according to the Air Quality Index (AQI) between satisfactory to moderate according to gas concentrations. The highest gas carbon monoxide (CO) concentration increase was close to dangerous in both sites, as it recorded 9.75µg/m3 in site#1 and 7.75µg/m3 in site#2. In conclusion, the AQI did not reach a poor level in these tested areas.","PeriodicalId":476841,"journal":{"name":"Maǧallaẗ al-handasaẗ wa-al-tiknūlūǧiyā","volume":"50 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136281649","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 : 2023-11-02DOI: 10.30684/etj.2023.142023.1516
Ahmed Ogaili, Mohsin Hamzah, Alaa Jaber, Ehsan Ghane
Effective structural monitoring maximizes efficiency in wind turbines, a crucial renewable energy asset. Using advanced condition monitoring techniques is crucial for reliability. This experiment shows how to use DWT and FFT for wind turbine blade fault detection. DWT allowed for multiresolution analysis of vibration signals from a healthy and eroded lab-scale turbine blade under controlled wind speeds. A 5-level DWT decomposition identified frequency sub-bands with localized fault information. The FFT post-processing of level 5 approximation coefficients revealed precise modal frequency shifts between blade states. The healthy blade showed a dominant 16 Hz mode that matched operational dynamics. Erosion caused a 24 Hz fault signature that was not present in the intact blade. Automated blade state classification was 98% accurate with 8 Hz modal separation. DWT's high sensitivity comes from nonstationary signal filtering and FFT's high-resolution spectral quantification. Comparative metric analysis confirmed DWT's superiority over FFT and statistical methods. The integrated approach combined complementary techniques to detect small defects that were previously unnoticeable. This study confirms the effectiveness of using DWT's strengths for monitoring wind turbine structural health in the future. The approach enables switching from time-based maintenance to data-driven prognostics, improving reliability by detecting failure precursors early. This study confirms DWT's effectiveness in identifying wind turbine blade faults and advancing critical techniques to prevent catastrophic failures.
{"title":"Application of Discrete Wavelet Transform for Condition Monitoring and Fault Detection in Wind Turbine Blades: An Experimental Study","authors":"Ahmed Ogaili, Mohsin Hamzah, Alaa Jaber, Ehsan Ghane","doi":"10.30684/etj.2023.142023.1516","DOIUrl":"https://doi.org/10.30684/etj.2023.142023.1516","url":null,"abstract":"Effective structural monitoring maximizes efficiency in wind turbines, a crucial renewable energy asset. Using advanced condition monitoring techniques is crucial for reliability. This experiment shows how to use DWT and FFT for wind turbine blade fault detection. DWT allowed for multiresolution analysis of vibration signals from a healthy and eroded lab-scale turbine blade under controlled wind speeds. A 5-level DWT decomposition identified frequency sub-bands with localized fault information. The FFT post-processing of level 5 approximation coefficients revealed precise modal frequency shifts between blade states. The healthy blade showed a dominant 16 Hz mode that matched operational dynamics. Erosion caused a 24 Hz fault signature that was not present in the intact blade. Automated blade state classification was 98% accurate with 8 Hz modal separation. DWT's high sensitivity comes from nonstationary signal filtering and FFT's high-resolution spectral quantification. Comparative metric analysis confirmed DWT's superiority over FFT and statistical methods. The integrated approach combined complementary techniques to detect small defects that were previously unnoticeable. This study confirms the effectiveness of using DWT's strengths for monitoring wind turbine structural health in the future. The approach enables switching from time-based maintenance to data-driven prognostics, improving reliability by detecting failure precursors early. This study confirms DWT's effectiveness in identifying wind turbine blade faults and advancing critical techniques to prevent catastrophic failures.","PeriodicalId":476841,"journal":{"name":"Maǧallaẗ al-handasaẗ wa-al-tiknūlūǧiyā","volume":"20 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135875189","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 : 2023-11-02DOI: 10.30684/etj.2023.141194.1487
Hasan Hussein, Ekhlas Fayyadh, Moayed Hasan
A significant heat flux affects the efficacy and durability of most equipment. Cooling these devices is the primary concern, prompting specialists to propose and investigate various solutions. For these applications, microchannels are regarded as a possibility. Experiments were conducted in this study to determine the effect of an electroplating coating on the characteristics of a single-phase flow. As the working fluid for the experiments, deionized water was used. During the investigations, a microchannel of 0.3mm width and 0.7mm depth with an average roughness of 18.64 nm was machined; the inlet temperature was maintained at 30°C, and the Reynolds number ranged from 109.2 to 2599. According to the results, the correlation between the fanning friction factor and laminar and turbulent flows can predict experimental findings with high precision. In addition, an increase in the Nusselt number correlates with an increase in the Reynolds number.When compared to a conventional microchannel, the models with an Al2O3 cladding have a fanning friction factor that is much greater. According to the results, a reliable correlation can be used to precisely estimate the friction factor of typical Al2O3-coated microchannels. The results demonstrated that the average value of the maximum thermal performance value was approximately 1.19 at low Reynolds numbers between 240-480 and then decreased as Reynolds numbers increased.
{"title":"Investigating the Effect of Electroplated Coatings on Single-Phase Fluid Flow and Heat Transfer in Microchannel","authors":"Hasan Hussein, Ekhlas Fayyadh, Moayed Hasan","doi":"10.30684/etj.2023.141194.1487","DOIUrl":"https://doi.org/10.30684/etj.2023.141194.1487","url":null,"abstract":"A significant heat flux affects the efficacy and durability of most equipment. Cooling these devices is the primary concern, prompting specialists to propose and investigate various solutions. For these applications, microchannels are regarded as a possibility. Experiments were conducted in this study to determine the effect of an electroplating coating on the characteristics of a single-phase flow. As the working fluid for the experiments, deionized water was used. During the investigations, a microchannel of 0.3mm width and 0.7mm depth with an average roughness of 18.64 nm was machined; the inlet temperature was maintained at 30°C, and the Reynolds number ranged from 109.2 to 2599. According to the results, the correlation between the fanning friction factor and laminar and turbulent flows can predict experimental findings with high precision. In addition, an increase in the Nusselt number correlates with an increase in the Reynolds number.When compared to a conventional microchannel, the models with an Al2O3 cladding have a fanning friction factor that is much greater. According to the results, a reliable correlation can be used to precisely estimate the friction factor of typical Al2O3-coated microchannels. The results demonstrated that the average value of the maximum thermal performance value was approximately 1.19 at low Reynolds numbers between 240-480 and then decreased as Reynolds numbers increased.","PeriodicalId":476841,"journal":{"name":"Maǧallaẗ al-handasaẗ wa-al-tiknūlūǧiyā","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135932819","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 : 2023-11-01DOI: 10.30684/etj.2023.142820.1547
Ameer Ahmed, Mohammed Fattah, Makki Mohsen
The foundation plays a significant role in safe and efficient turbo machinery operation. Turbomachinery generates harmonic load on the foundation due to its high-speed rotating motion, which causes vibration in the machinery foundation. Any increase in machine vibration reduces the machine's performance. In studying engineering problems, using numerical programs helps get a well-designed foundation. Before conducting a parametric study, the program used shall be validated and/or verified by conducting a series of analyses to ensure that the program output represents the reference studied cases well. In many cases, the real problem is simplified by assuming that the machine's loads are applied at the upper slab of the frame foundation. The present work included the effect of the machine's mass elevation on the response of a high-speed turbo machine's frame foundation. The mass elevations of (12.6, 13.0, 13.3, 13.6, 13.9, and 14.2) m are selected for the dynamic analyses. A verification process is carried out to calculate the three-dimensional frame foundation's natural frequencies and mode shapes using Ansys software. The results show that the machine's masses must be included and applied at its specific elevation to reflect the true dynamic vertical response of the system as far as the mass height to top slab elevation ratio exceeds 5%. The results show a good agreement in calculating static and modal analysis with the study case. When neglecting the machine mass, the difference between the calculated natural frequencies for any mode shape is less than 10%.
{"title":"A Static and Dynamic Analysis of A High-Speed Turbo Machine Foundation","authors":"Ameer Ahmed, Mohammed Fattah, Makki Mohsen","doi":"10.30684/etj.2023.142820.1547","DOIUrl":"https://doi.org/10.30684/etj.2023.142820.1547","url":null,"abstract":"The foundation plays a significant role in safe and efficient turbo machinery operation. Turbomachinery generates harmonic load on the foundation due to its high-speed rotating motion, which causes vibration in the machinery foundation. Any increase in machine vibration reduces the machine's performance. In studying engineering problems, using numerical programs helps get a well-designed foundation. Before conducting a parametric study, the program used shall be validated and/or verified by conducting a series of analyses to ensure that the program output represents the reference studied cases well. In many cases, the real problem is simplified by assuming that the machine's loads are applied at the upper slab of the frame foundation. The present work included the effect of the machine's mass elevation on the response of a high-speed turbo machine's frame foundation. The mass elevations of (12.6, 13.0, 13.3, 13.6, 13.9, and 14.2) m are selected for the dynamic analyses. A verification process is carried out to calculate the three-dimensional frame foundation's natural frequencies and mode shapes using Ansys software. The results show that the machine's masses must be included and applied at its specific elevation to reflect the true dynamic vertical response of the system as far as the mass height to top slab elevation ratio exceeds 5%. The results show a good agreement in calculating static and modal analysis with the study case. When neglecting the machine mass, the difference between the calculated natural frequencies for any mode shape is less than 10%.","PeriodicalId":476841,"journal":{"name":"Maǧallaẗ al-handasaẗ wa-al-tiknūlūǧiyā","volume":"19 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135714496","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 : 2023-10-29DOI: 10.30684/etj.2023.142412.1530
Rawa Mohammed, Ayad Shahab
Two routes, BC and C, were scrutinized, and the outcomes displayed significant enhancements in properties for the recycled chips after the hot extruded and ECAP techniques. After the fourth run, route BC exhibited a maximum Ultimate tensile strength of 265 MPa, peak yield strength of 149 MPa, and an elongation to failure of 46%. Meanwhile, the corresponding values for route C were 238 MPa, 136 MPa, and 41%, respectively. For two routes, BC and C, every pass led to elevated strength and hardness while also contributing to increased elongation to failure. The microstructures and mechanical characteristics of the ECAPed samples surpassed those of the extruded sample. The routes and pass numbers substantially impacted the microstructures and mechanical properties of the solid-state recycled AA6061-T4 alloy chip specimens. Scanning electron microscopy pictures showcased a honeybee-type pattern following ECAP through route BC, signifying the final stages of grain refinement. At the same time, the initial sample exhibited a fracture tendency with a mix of brittleness and ductility.
{"title":"Effect of ECAP Routes on Mechanical Properties and Microstructure of AA6061-T4 Recycled Chips","authors":"Rawa Mohammed, Ayad Shahab","doi":"10.30684/etj.2023.142412.1530","DOIUrl":"https://doi.org/10.30684/etj.2023.142412.1530","url":null,"abstract":"Two routes, BC and C, were scrutinized, and the outcomes displayed significant enhancements in properties for the recycled chips after the hot extruded and ECAP techniques. After the fourth run, route BC exhibited a maximum Ultimate tensile strength of 265 MPa, peak yield strength of 149 MPa, and an elongation to failure of 46%. Meanwhile, the corresponding values for route C were 238 MPa, 136 MPa, and 41%, respectively. For two routes, BC and C, every pass led to elevated strength and hardness while also contributing to increased elongation to failure. The microstructures and mechanical characteristics of the ECAPed samples surpassed those of the extruded sample. The routes and pass numbers substantially impacted the microstructures and mechanical properties of the solid-state recycled AA6061-T4 alloy chip specimens. Scanning electron microscopy pictures showcased a honeybee-type pattern following ECAP through route BC, signifying the final stages of grain refinement. At the same time, the initial sample exhibited a fracture tendency with a mix of brittleness and ductility.","PeriodicalId":476841,"journal":{"name":"Maǧallaẗ al-handasaẗ wa-al-tiknūlūǧiyā","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136157538","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 : 2023-10-28DOI: 10.30684/etj.2023.142219.1523
Nashwan Mahmood, Mohammed Hikmat
The effect of calcium carbonate nanoparticles (CaCO3) on the mechanical and thermal properties of various polymers was investigated in this review. The results were compared to scholarly research published between 2002-2022. Different polymers were evaluated, including Polypropylene (PP), High-density polyethylene (HDPE), Polyvinyl chloride (PVC), Low-density polyethylene (LDPE), Polyethylene (PE), and natural rubber (NR). Through this work, the effect of CaCO3 nanoparticles that act as fillers in polymeric materials has been reviewed. It can be concluded that mechanical and thermal properties can be decreased, increased, or unchanged by increasing and decreasing the fillers to obtain optimal results. It is reasonable to conclude that most papers with nano-CaCO3 showed improvements in appreciable mechanical and thermal properties. In general, the term "surface modification of inorganic fillers" refers to the coating of the fillers with organic materials, which can be done by physical and chemical interactions between the modifiers and the fillers. The reviewed articles revealed that modification of CaCO3 nanoparticles with surface pre-treatment fillers caused enhancement of the mechanical properties of the polymeric matrix twice and prevented the agglomeration of particles in the matrix. Various mixing methods have been used, the most significant being a twin screw extruder, mechanical stirrer, and two-roll mill.
{"title":"The Effect of Calcium Carbonate-Nanoparticle on the Mechanical and Thermal Properties of Polymers Utilizing Different Types of Mixing and Surface Pre-Treatment: A Review Paper","authors":"Nashwan Mahmood, Mohammed Hikmat","doi":"10.30684/etj.2023.142219.1523","DOIUrl":"https://doi.org/10.30684/etj.2023.142219.1523","url":null,"abstract":"The effect of calcium carbonate nanoparticles (CaCO3) on the mechanical and thermal properties of various polymers was investigated in this review. The results were compared to scholarly research published between 2002-2022. Different polymers were evaluated, including Polypropylene (PP), High-density polyethylene (HDPE), Polyvinyl chloride (PVC), Low-density polyethylene (LDPE), Polyethylene (PE), and natural rubber (NR). Through this work, the effect of CaCO3 nanoparticles that act as fillers in polymeric materials has been reviewed. It can be concluded that mechanical and thermal properties can be decreased, increased, or unchanged by increasing and decreasing the fillers to obtain optimal results. It is reasonable to conclude that most papers with nano-CaCO3 showed improvements in appreciable mechanical and thermal properties. In general, the term \"surface modification of inorganic fillers\" refers to the coating of the fillers with organic materials, which can be done by physical and chemical interactions between the modifiers and the fillers. The reviewed articles revealed that modification of CaCO3 nanoparticles with surface pre-treatment fillers caused enhancement of the mechanical properties of the polymeric matrix twice and prevented the agglomeration of particles in the matrix. Various mixing methods have been used, the most significant being a twin screw extruder, mechanical stirrer, and two-roll mill.","PeriodicalId":476841,"journal":{"name":"Maǧallaẗ al-handasaẗ wa-al-tiknūlūǧiyā","volume":"297 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136159317","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 : 2023-10-28DOI: 10.30684/etj.2023.142505.1538
Charles Ike
This paper presents analytical solutions for the buckling of thick beams. The Bernoulli-Euler beam theory (BEBT) overestimates their critical buckling load. This paper has derived a cubic polynomial shear deformation beam buckling theory (CPSDBBT) from first principles using the Euler-Lagrange differential equation (ELDE). It develops closed-form solutions to differential equations using the finite sine transform method. The formulation considers transverse shear deformation and satisfies the transverse shear stress-free boundary conditions. The governing equation is developed from the energy functional, ∏ , by applying the ELDE. The domain equation is obtained as an ordinary differential equation (ODE). The finite sine transformation of the ODE transforms the thick beam, which is considered an algebraic eigenvalue problem. The solution gives the buckling load N xx at any buckling mode n. The critical buckling load N xx cr occurs at the first buckling mode and is presented in depth ratios to span (h/l). It is found that and agrees with previous solutions using shear deformable theories. For / 0
{"title":"An Analytical Solution to Buckling of Thick Beams Based on a Cubic Polynomial Shear Deformation Beam Theory","authors":"Charles Ike","doi":"10.30684/etj.2023.142505.1538","DOIUrl":"https://doi.org/10.30684/etj.2023.142505.1538","url":null,"abstract":"This paper presents analytical solutions for the buckling of thick beams. The Bernoulli-Euler beam theory (BEBT) overestimates their critical buckling load. This paper has derived a cubic polynomial shear deformation beam buckling theory (CPSDBBT) from first principles using the Euler-Lagrange differential equation (ELDE). It develops closed-form solutions to differential equations using the finite sine transform method. The formulation considers transverse shear deformation and satisfies the transverse shear stress-free boundary conditions. The governing equation is developed from the energy functional, ∏ , by applying the ELDE. The domain equation is obtained as an ordinary differential equation (ODE). The finite sine transformation of the ODE transforms the thick beam, which is considered an algebraic eigenvalue problem. The solution gives the buckling load N xx at any buckling mode n. The critical buckling load N xx cr occurs at the first buckling mode and is presented in depth ratios to span (h/l). It is found that and agrees with previous solutions using shear deformable theories. For / 0","PeriodicalId":476841,"journal":{"name":"Maǧallaẗ al-handasaẗ wa-al-tiknūlūǧiyā","volume":"186 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136233712","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 : 2023-10-24DOI: 10.30684/etj.2023.140948.1477
Natiq Fadhil, Amer Aldabbagh, Falah Hatem
Experiments are conducted to investigate the heat transfer and pressure drop characteristics of corrugated tubes and rod baffles in a shell-and-tube heat exchanger. One of the effective techniques to improve heat transfer is to use corrugated tubes. This article investigates rod baffles with varied corrugation depths and corrugated tubes for (1 start). In the heat exchanger's shell side, where a constant wall temperature was attained on the tube side, water was employed as the working fluid after being heated at the wall. Corrugation ratios (e/dh) of 0.1 and 0.13, pitch (p) of 10, 20, and 30mm, and two types (x/d) of 1.25 and 1.375 were used. The study was conducted throughout the Reynolds number turbulent range (4,000 to 24,000). The results manifested that the average Nusselt number of the corrugated tubes (pitch-10mm) for (x/d=1.25) increased by 25 and 55 percent for the corrugation depths of 0.1 and 0.13, respectively. The average Nusselt number for (x/d=1.375) is increased by 38% and 59% for the corrugation depths of 0.1 and 0.13, respectively. Nevertheless, the average friction factor of the corrugated tube with (e/dh) = 0.1 and 0.13 is higher than that of the smooth tube by 66% and 130%, respectively, and it decreases as the corrugation pitch and (x/d) are increased. When a corrugated tube and a rod baffle with a corrugated depth (e=2.1mm) and pitch (p=10mm) were used, the thermal enhancement factor was 1.9 for (x/d=1.25) and 1.97 for (x/d=1.375) at the same pumping power.
{"title":"Experimental Study of the Double Pipe Heat Exchanger for Heat Transfer and Pressure Drop Characteristics of the Grooved Tube","authors":"Natiq Fadhil, Amer Aldabbagh, Falah Hatem","doi":"10.30684/etj.2023.140948.1477","DOIUrl":"https://doi.org/10.30684/etj.2023.140948.1477","url":null,"abstract":"Experiments are conducted to investigate the heat transfer and pressure drop characteristics of corrugated tubes and rod baffles in a shell-and-tube heat exchanger. One of the effective techniques to improve heat transfer is to use corrugated tubes. This article investigates rod baffles with varied corrugation depths and corrugated tubes for (1 start). In the heat exchanger's shell side, where a constant wall temperature was attained on the tube side, water was employed as the working fluid after being heated at the wall. Corrugation ratios (e/dh) of 0.1 and 0.13, pitch (p) of 10, 20, and 30mm, and two types (x/d) of 1.25 and 1.375 were used. The study was conducted throughout the Reynolds number turbulent range (4,000 to 24,000). The results manifested that the average Nusselt number of the corrugated tubes (pitch-10mm) for (x/d=1.25) increased by 25 and 55 percent for the corrugation depths of 0.1 and 0.13, respectively. The average Nusselt number for (x/d=1.375) is increased by 38% and 59% for the corrugation depths of 0.1 and 0.13, respectively. Nevertheless, the average friction factor of the corrugated tube with (e/dh) = 0.1 and 0.13 is higher than that of the smooth tube by 66% and 130%, respectively, and it decreases as the corrugation pitch and (x/d) are increased. When a corrugated tube and a rod baffle with a corrugated depth (e=2.1mm) and pitch (p=10mm) were used, the thermal enhancement factor was 1.9 for (x/d=1.25) and 1.97 for (x/d=1.375) at the same pumping power.","PeriodicalId":476841,"journal":{"name":"Maǧallaẗ al-handasaẗ wa-al-tiknūlūǧiyā","volume":"55 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135315902","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 : 2023-10-13DOI: 10.30684/etj.2023.142048.1517
Abeer Radhi, Sami Jafar Al-Rubaiey, Shaymaa Al-Rubaye
Carbon fiber cloths (CFCs) are essential materials extensively studied and utilized in numerous applications, including supercapacitors (SCs), batteries, solar cells, and catalysis. CFC is gaining significant research attention as an inexpensive choice for (SC) electrode materials, mainly owing to its peculiar adaptability, which makes it suitable for conveyable or flexible devices. In fact, this characteristic is not easily attainable with other carbon-based matrices. However, bare CFC electrodes face difficulties concerning their capacitive performance because of numerous factors, including markedly little surface space, poor electrochemical efficacy, and limited porousness. In this way, these factors reduce their efficiency as supercapacitor electrodes. To address this, the incorporation of transition metal oxides (TMOs) and conducting polymers (CPs) within the CFC is expected to be crucial in developing the electrochemical performance. This work thoroughly reviews the design and the modification of (CFC) that provide high-performance electrode supercapacitors. It emphasizes implementing effective approaches, such as active material loading, specifically focusing on iron oxides. The SCs have high working potentials and can effectively increase their energy density by iron oxides. According to the researchers’ findings, combining CFC and FeCo2O4 has a high electrochemical performance and potential range in aqueous electrolytes. Additionally, this paper outlines and highlights the recent advancements in developing iron oxides-CFC and iron oxides/CP-CFC for supercapacitor applications. It explores their design approaches and electrochemical properties, offering insights into future opportunities for energy storage technologies.
{"title":"Carbon Fiber Cloth Performance Improvement via Hybrid Materials (Fe2O3, FeCo2O4, and Conducting Polymer) Addition for Energy Storage Applications","authors":"Abeer Radhi, Sami Jafar Al-Rubaiey, Shaymaa Al-Rubaye","doi":"10.30684/etj.2023.142048.1517","DOIUrl":"https://doi.org/10.30684/etj.2023.142048.1517","url":null,"abstract":"Carbon fiber cloths (CFCs) are essential materials extensively studied and utilized in numerous applications, including supercapacitors (SCs), batteries, solar cells, and catalysis. CFC is gaining significant research attention as an inexpensive choice for (SC) electrode materials, mainly owing to its peculiar adaptability, which makes it suitable for conveyable or flexible devices. In fact, this characteristic is not easily attainable with other carbon-based matrices. However, bare CFC electrodes face difficulties concerning their capacitive performance because of numerous factors, including markedly little surface space, poor electrochemical efficacy, and limited porousness. In this way, these factors reduce their efficiency as supercapacitor electrodes. To address this, the incorporation of transition metal oxides (TMOs) and conducting polymers (CPs) within the CFC is expected to be crucial in developing the electrochemical performance. This work thoroughly reviews the design and the modification of (CFC) that provide high-performance electrode supercapacitors. It emphasizes implementing effective approaches, such as active material loading, specifically focusing on iron oxides. The SCs have high working potentials and can effectively increase their energy density by iron oxides. According to the researchers’ findings, combining CFC and FeCo2O4 has a high electrochemical performance and potential range in aqueous electrolytes. Additionally, this paper outlines and highlights the recent advancements in developing iron oxides-CFC and iron oxides/CP-CFC for supercapacitor applications. It explores their design approaches and electrochemical properties, offering insights into future opportunities for energy storage technologies.","PeriodicalId":476841,"journal":{"name":"Maǧallaẗ al-handasaẗ wa-al-tiknūlūǧiyā","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135854637","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 : 2023-10-13DOI: 10.30684/etj.2023.141759.1511
Ali Alibraheem, Basil Al-Shathr
Slurry-infiltrated fiber concrete (SIFCON) is a comparatively new and unique steel fiber-reinforced concrete (FRC) form. SIFCON possesses many desirable characteristics, including high strength and ductility. Sustainable concrete is one of the most critical types of concrete for the current environment. An enormous volume of waste rubber tires is produced globally due to the expansion of the automobile industry. This study's primary purpose is to assess the impact of employing pre-treated waste rubber tires in slurry-infiltrated fiber concrete on its flexural and compressive strengths. Based on flexural and compressive strengths, an experimental program was conducted to evaluate the flexural and compressive strengths of SIFCON containing 4% steel fiber and 6%, 8%, and 10% waste rubber. Different pre-treatment methods were used to improve the bonding between the cement paste and rubber particles, including Na(OH) solution, Ca(OH)2 solution, and pre-treatment using Cempatch AB solution. Compressive and flexural strength decreased with increasing waste rubber content, up to 43% and 37% for a 10% waste rubber content, respectively. Moreover, The test results showed that the pre-treatment of chopped rubber with NaOH solution produced the highest values for compressive and flexural strength, giving strong polarity groups to the surface of the rubber and generating a strong chemical interaction between the rubber and the cement matrix.
{"title":"Waste Rubber Pre-treatments and Their Effects on Compressive and Flexural Strength of Modified SIFCON","authors":"Ali Alibraheem, Basil Al-Shathr","doi":"10.30684/etj.2023.141759.1511","DOIUrl":"https://doi.org/10.30684/etj.2023.141759.1511","url":null,"abstract":"Slurry-infiltrated fiber concrete (SIFCON) is a comparatively new and unique steel fiber-reinforced concrete (FRC) form. SIFCON possesses many desirable characteristics, including high strength and ductility. Sustainable concrete is one of the most critical types of concrete for the current environment. An enormous volume of waste rubber tires is produced globally due to the expansion of the automobile industry. This study's primary purpose is to assess the impact of employing pre-treated waste rubber tires in slurry-infiltrated fiber concrete on its flexural and compressive strengths. Based on flexural and compressive strengths, an experimental program was conducted to evaluate the flexural and compressive strengths of SIFCON containing 4% steel fiber and 6%, 8%, and 10% waste rubber. Different pre-treatment methods were used to improve the bonding between the cement paste and rubber particles, including Na(OH) solution, Ca(OH)2 solution, and pre-treatment using Cempatch AB solution. Compressive and flexural strength decreased with increasing waste rubber content, up to 43% and 37% for a 10% waste rubber content, respectively. Moreover, The test results showed that the pre-treatment of chopped rubber with NaOH solution produced the highest values for compressive and flexural strength, giving strong polarity groups to the surface of the rubber and generating a strong chemical interaction between the rubber and the cement matrix.","PeriodicalId":476841,"journal":{"name":"Maǧallaẗ al-handasaẗ wa-al-tiknūlūǧiyā","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135858583","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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