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Around the world, there is a significant increase in the number of electric vehicles on the roads. Among the reasons are the aims to reduce the global dependency on oil as an energy source due to its political and economic dimensions especially for the non-oil producing countries by maximizing the use of electric vehicles. At the same time, it is also due to global concerns for the environmental aspect, especially global warming where transportation represents 30% of it. The battery is considered the main source of power for electric vehicles, but the battery tends to generate a significant amount of heat due to internal resistance during operation. The generated heat during the charging/discharging processes could lead to overheating in the battery which could end in battery failure. Therefore, dissipating the generated heat in the EV battery becomes essential through thermal management systems to ensure that the battery operates within a safe temperature range. Hence, the present study aims to introduce a new design of the liquid cooling system and also to investigate the effective parameter which affects its heat transfer performance. This paper is part of the overall study and describes the computational fluid dynamics by using ANSYS FLUENT software and numerical analysis to investigate the effect of the inlet/outlet arrangements on the heat transfer performance of a new LCP used for cooling the EV battery cell. There are three inlet/outlet arrangements: I-arrangement, Z-arrangement, and L-arrangement. The flow rate range of the present study is at the range of 0.4 – 1.6 l/min under 300 W heat flux. The L-arrangement has the best cooling performance compared to I-arrangement and Z-arrangement, where it achieves an average battery cell temperature which equals to 37.1 ⁰C along flow rates, while it is at 43.3 ⁰C and 38.0 ⁰C for I-arrangement and Z-arrangement, respectively. The temperature uniformity for both L-arrangement and Z-arrangement is almost similar, and they achieved good temperature uniformity at all flow rates, while I-arrangement failed to achieve good temperature uniformity at the lowest flow rates.

This paper presents a comprehensive review on the battery especially Lithium-ion batteries and the battery thermal management systems for electric vehicles. The basics of the battery system and thermal issues related to the battery have been highlighted. Different battery thermal management systems have been discussed in the review. This paper has presented different thermal management systems for electric vehicle battery in details. Air cooling, phase change, and liquid cooling are studied in the reviewed literature, by showing and discussing the results of the previous studies in these fields. Most promising thermal management system is the liquid cooling, because it has the best cooling potential for the EV batteries which gets the researchers attention to improve it based on wide number of increasing studies and developments in the EV liquid cooling systems. Improving the hydraulic and thermal performance of the liquid cold plate which is part of the EV liquid colling systems has not widely been explored in the fields of developing inlets design, outlets, and fins. The review paper could guide the researchers to innovate better liquid cooling systems and improve their cooling and hydraulic performance in battery thermal management systems.

The current numerical paper introduces the flow and heat transfer characteristics across a new configuration channel, namely: the curved-corrugated channel, using binary hybrid nanofluid. E-shaped baffles with different geometrical parameters have been employed while CuO / MgO-water nanofluid is experimentally prepared with different volume fractions 0.0–5%. Measured thermophysical properties is utilized to simulate the flow and heat transfer characteristics by adopting the κ-e model. The influences of corrugations, baffles, and geometric parameters; gap ratio (GR = 0.2,0.3,0.4, and 0.5), blockage ratio (BR = 0.2,0.25,0.3, and 0.35), and pitch angle (β = 10°, 12.5°, and 15°) at different Reynolds number (8000–28000) are evaluated using thermal–hydraulic performance method. The outcomes show that vortex flow and increased turbulence will increase heat transfer due to influences of corrugations and baffles. It is confirmed that the flow variations governed by the geometric parameters of the design and the best performance produce at lowest pitch angle 10°, lowest gap ratio (GR = 0.2) and highest blocking ratio (BR = 0.35). Regards the fluid medium, CuO / MgO particles improve the thermophysical properties of the base fluid and thereby boost the thermal performance of the system. It has found new correlations between the Nusselt number, friction Factor and design parameters of tested channel with using binary hybrid nanofluid.

In this study, flow and heat transfer characteristics of binary hybrid nanofluid (CuO / MgO-water) through new configuration channel, namely: the curved-corrugated channel, are evaluated numerically using the multi-phase mixture model. The binary hybrid nanofluid is experimentally prepared with average diameters of 40 nm and three volume fractions of nanoparticles of 1%,3%, and 5%. Measured thermophysical properties are employed to simulate the complex flow within the tested configurations of channel with presence of E-shaped baffles. Various geometric parameters such as gap ratio (GR = 0.2,0.3,0.4, and 0.5), blockage ratio (BR = 0.2,0.25,0.3, and 0.35), and pitch angle (β = 10°, 12.5°, and 15°) at different Reynolds number (8000–28,000) and volume fraction (φ) of CuO / MgO particles (0–5%) are considered to serve the purpose. The findings uncover that the binary hybrid nanofluid improves the thermophysical properties of the base fluid and thereby boost the thermal performance of the system. It is found that the thermal-hydraulic performance (THPF) of binary hybrid nanofluid enhances with increasing volume fraction, and this enhancement is close to 38% when Re = 28,000 and φ = 0.05. Regards the geometric parameters, THPF enhances by increasing the blockage ratio and decreasing the pitch angle while recording the best improvement at the particular gap ratio, i.e. 0.3.

Bamboo is an abundant natural resource in Asia and one of the high potential fibers used to reinforce polymer composites. This article presents a comparative study on the physicochemical and thermal properties of bamboo fiber (BF) from Gigantochloa scortechinii for untreated BF, steam explosion (SE) treatment BF, and steam explosion followed by alkali (SE-alkali) treatment BF. The physicochemical and thermal properties of BF were determined using energy dispersive X-ray (EDX) spectroscopy and thermogravimetric analysis (TGA), while scanning electron microscopy (SEM) was used to examine the surfaces morphologies. A Fourier transform infrared (FTIR) spectroscopy was utilized to detect the presence of functional groups. TGA results showed that SE BF was significantly more thermally stable than the untreated BF and SE-alkali treatment BF. Major changes in chemical composition and surface morphology of the bamboo fibers indicated that hemicellulose and lignin were removed by SE-alkali treatment. In conclusion, the BF surface is physically and chemically modified by the SE-alkali treatment.

Gigantochloa scortechinii is one of the most well-known bamboo species in Malaysia because of its advantageous physical, morphological and strength properties. This study presented the effect of al...

Fibers are widely used to reinforce polymer composites for various applications because of their mechanical properties and ease of manufacturing. Fiber reinforced polymers are being developed using synthetic fibers and natural fibers, including bamboo, bagasse, etc. The main goal of this work is to optimize the mechanical properties of bamboo mesoparticle/nylon 6 composites using a response surface methodology. The conditions used to achieve an optimal tensile strength, flexural strength, and impact strength were determined using a Box-Behnken design with three operational variables: alkali concentration, particle loading, and particle size. Based on the experimental design, experimental tests were conducted to develop a mathematical model and predict the mechanical properties of the bamboo mesoparticle/nylon 6 composites. The optimal conditions to produce a composite with a maximum tensile strength were achieved at an alkali concentration of 4 wt.%, a particle size of 1 μm, and a particle loading of 13.5 wt.%. The optimum conditions to produce a composite with a maximum flexural strength were achieved at an alkali concentration of 2 wt.%, a particle size of 1 μm, and a particle loading of 13.5 wt.%. Additionally, an alkali concentration of 4 wt.%, a particle size of 1 μm, and a particle loading of 9 wt.% produced a composite with the maximum impact strength. Overall, the results showed that the values predicted using the model correlated with the experimental values.

The aim of this study was to investigate the mechanical properties of bamboo mesoparticle/nylon 6 composites. The challenge in this paper is that there has been very limited research done on the effect of fibre loading on the mechanical properties of natural bamboo mesoparticles as reinforcement for nylon 6 in order to reduce the cost of production while maintaining the high composite mechanical properties. The average size of the bamboo mesoparticles used was 0.25 μm. The mesoparticle/nylon 6 composites were prepared by mixing bamboo mesoparticles and nylon 6 using a laboratory blender mixer machine, followed by preparation of samples using an injection moulding machine. The fibre loadings were 9 wt.%, 13 wt.%, and 18 wt.%. The mechanical properties of the composites examined were tensile, flexural, and impact properties, while tensile fracture surfaces of the mesocomposites were examined using scanning electron microscopy. The results showed that 13 wt.% fibre loading has the best tensile strength and modulus with improvements of 15% and 25%, respectively, compared to neat nylon 6. A slight increase in the flexural strength and modulus with increasing fibre loading from 9 to 13 wt.% was observed. However, a lack of performance was observed in the impact strength of the bamboo mesoparticle/nylon 6 composites. Electron microscopic examination revealed no filler clumping aggregation and less void formation when 13 wt.% fibre loading was used, which indicates that a relatively high amount of energy was consumed to break the 13 wt.% bamboo mesoparticle/nylon 6 composites. Overall, the results indicated that the tensile and mechanical properties of bamboo mesoparticle/nylon 6 composites increased with increased fibre loadings.

Plastics have remained the material of choice, and after serving their intended purpose, a large proportion ends up in the environment where they persist for centuries. The packaging industry is the largest and growing consumer of synthetic plastics derived from fossil fuels. Food packaging plastics account for the bulk of plastic waste that are polluting the environment. Additionally, given the fact that petroleum reserves are finite and facing depletion, there is a need for the development of alternative materials that can serve the same purpose as conventional plastics. This paper reviews the function of packaging materials and highlights the future potential of the adoption of green materials. Biopolymers have emerged as promising green materials although they still have very low market uptake. Polylactic acid (PLA) has emerged as the most favoured bioplastic. However, it is limited by its high cost and some performance drawbacks. Blending with agricultural waste and natural fillers can result in green composites at low cost, low greenhouse gas emissions, and with improved performance for food packaging applications. The continent of Africa is proposed as a rich source of fibres and fillers that can be sustainably exploited to fabricate green composites in a bid to achieve a circular economy.

The increased probability of fire occurrence in urban tunnels has led researchers to investigate this issue extensively. Although fire can occur at any point in a tunnel, the effect of fire source position on temperature distribution has not received considerable attention in most of previous investigations. In this research, the influences of varying horizontal fire source locations on temperature diffusion in particular maximum smoke temperature stratification beneath the ceiling has been investigated. A set of scale-down experiments was performed in a model tunnel [3 m (length) × 0.6 m (width) × 0.96 m (height)]. n-Heptane and gasoline were used as fuels in rectangular pools to generate a heat source. The analysis reveals that typical temperature curves have a similar trend when the fire source location changes. Furthermore, the temperature profile tip (maximum smoke temperature) is located between the burner and the origin of the tunnel. The modified model of maximum temperature, which considers the horizontal fire source location, is defined. The results here complement existing literature where the effects of variable fire position in a tunnel have not been considered.

The study systematically explored the effect of alkali concentration and soaking time on the microstructure and tensile properties of single-cellulosic Buluh Semantan. Scanning electron microscopy and tensile tests were conducted to determine the effects of different alkali treatments on the properties of the single-cellulosic bamboo fibers. In particular, the effects of NaOH concentration and soaking time on the tensile properties of the single-cellulosic bamboo fiber were investigated. The single-cellulosic bamboo fiber was immersed in 2, 4, 6, and 8 wt.% aqueous NaOH solutions for soaking times of 1, 3, 6, 12, 18, and 24 h. The tensile properties of the fiber increased after each alkali treatment. The alkali concentration and soaking time significantly affected the fiber properties. The ultimate tensile strength of the single-cellulosic Buluh Semantan treated with 2 wt.% NaOH for 12 h decreased to 214 MPa relative to the fibers that experienced water retting. The highest tensile strength herein was 356.8 MPa for the single-cellulosic fiber that was soaked for 12 h in 4 wt.% NaOH. Comparatively, the tensile strength of the single-cellulosic bamboo fiber that was soaked for 12 h in 8 wt.% NaOH was 234.8 MPa. The tensile modulus of the single-cellulosic fiber was 12.06 GPa after soaking in 8 wt.% NaOH for 18 h, indicating that a strong alkali treatment negatively affected the stiffness and suitability for use of the fibers in applications. The topography of the fiber surface became much rougher after the alkali treatments due to the removal of hemicellulose and other surface impurities. The alkali treatments substantially changed the morphology of the fiber surface, suggesting an increase in wettability.

This paper discusses the behaviour of different thermophysical properties of CuO water-based nanofluids, including the thermal and hydraulic performance and pumping power. Different experimental and theoretical studies that investigated each property of CuO/water in terms of thermal and fluid mechanics are reviewed. Classical theories cannot describe the thermal conductivity and viscosity. The concentration, material, and size of nanoparticles have important roles in the heat transfer coefficient of CuO/water nanofluids. Thermal conductivity increases with large particle size, whereas viscosity increases with small particle size. The Nusselt number depends on the flow rate and volume fraction of nanoparticles. The causes for these behaviour are discussed. The magnitude of heat transfer rate is influenced by the use of CuO/water nanofluids. The use of CuO/water nanofluids has many issues and challenges that need to be classified through additional studies.

This investigation aims to study the mechanical properties of the bamboo particle (BP) (Gigantochloa scortechinii) reinforced with semirigid Polyvinyl Chloride (PVC) composites before and after the steam explosion (SE)-alkali treatment. Mechanical properties, namely, tensile, flexural and impact strengths, were determined using universal tensile and impact testing machines according to ASTM standard. The tensile and flexural strengths of the composites were improved after SE-alkali treatment. Results indicated that the tensile and flexural strengths of the composites increased and reached the optimum values of 17.42 and 11.86 MPa, respectively for SE-alkali treatment BP reinforced semirigid PVC with 40 wt% particle content. The impact strength of SE-alkali-treated composites was unimproved due to less dense and rigid particle.

In this paper, after a short review of the heat exchangers (HEX) types and applications with different technologies was presented, a lot of parameters which mainly affect the thermal-hydraulic performance of heat exchangers have been offered to characterize the optimal design of HEX. It can be seen that the presence of a fin in a smooth channel or tube provides the best overall performance of HEX. Furthermore, the use of a vortex generator, which is considered prominent passive method, significantly increases the rate of heat transfer and reduces the pressure drop. Finally, the current review provides some recommendations for future studies to enhance the performance of HEX.

Using metallic materials in automotive structures increases weight, fuel consumption and cost, therefore, certain trends have begun to use lightweight and cheaper materials. Fibre composites are used in automotive applications because they are stiff, lightweight and stronger than bulk material, as well as they have a comparable energy-absorbing capacity to that of metallic materials. The aim of this study is to investigate the potentials in natural ramie/bio-epoxy composite in crash energy absorption applications. Cubic specimens consisted of 12, 24 and 30 plies of ramie/bio-epoxy laminates with 50, 80 and 120 mm long which were prepared by hand layup method. Static axial compression load was then applied and the energy-absorbing capability of the ramie/epoxy composite was evaluated. The crashworthiness characteristics of the composite tubes were evaluated by measuring the average and peak crushing load, specific energy absorption, total absorbed energy and crush force efficiency in quasi-static axial compression. The failure mode and behaviour of the tubes were investigated by taking photographs and recording the load–displacement curves during the test accomplishment. The test results indicated that natural ramie/bio-epoxy composite tube has the great potential to be used as an effective energy-absorbing device.

This study focuses on failure response and energy absorption of woven ramie epoxy square composite tubes when exposed to the axial quasi-static compression test. Hand lay-up technique was used to prepare the rectangular composite tubes composed of 12 layers of ramie fabric with a thickness of 1.7 mm and 50-, 80-, and 120-mm-long tubes. The measured parameters were specific energy absorption, energy absorption, and peak load. The total energy absorption increased with the increase in the length of the tubes. The failure mode of the tested tubes was examined, and the mid-length and local buckling were considered as the main sources of failure. The woven natural ramie was used in the textiles for years. However, the results of this paper can be significant because of the limited research employing woven ramie as reinforcement for composites.

This paper presents the experimental and analytical investigation of four air-based bifacial photovoltaic thermal collectors. The experiments were performed on four bifacial PV panels with four different packing factors and four different configurations of air-based PVT collectors. A mathematical model was developed to evaluate the energy and exergy performance of the collectors. The four designs were studied in under the steady-state conditions. All four models of photovoltaic thermal collectors were fabricated and indoor experimental studies were conducted using the solar simulator. The double-path parallel flow design indicated the highest total energy efficiency of 51%–67%, and the single-path design indicated the lowest total energy efficiency of 28%–49%, at a 0.7 packing factor. The single-path collector design is the best option if electrical energy is the dominant desired output energy. However, double-path parallel flow design is the best option if the thermal energy is the dominant desired output energy. In addition, the single-path design had the highest exergy efficiency (8.2%–8.4%) followed by double-path parallel flow design (7.2%–8%).

Humidity during the fabrication of natural fibre reinforced composites can harm their mechanical performance. This study examines the effect of humidity during the fabrication of unidirectional kenaf/polylactic acid (PLA) biocomposites on their dynamic and static mechanical properties. Kenaf fibres were conditioned at different relative humidity (RH) levels (40% RH, 60% RH and 80% RH) before being pressed with PLA to form biocomposites. Kenaf/PLA biocomposites were analysed using dynamic mechanical analysis, fracture toughness in mode II, tensile and flexural. Results indicated that the value of GIIC and storage modulus decreased when the relative humidity increased. Reduced tensile and flexural modulus were observed when kenaf was exposed to high relative humidity of 80% RH. However, the form of unidirectional kenaf affected the properties and reduced the drop value in the tensile modulus. The optimum relative humidity to produce kenaf/PLA biocomposites is 40% RH.

Here, the researchers carried out an experimental analysis of the effect of the TiO2 nanosolution concentration on the heat transfer of the twin jet impingement on an aluminum plate surface. We used three different heat transfer enhancement processes. We considered the TiO2 nanosolution coat, aluminum plate heat sink, and a twin jet impingement system. We also analyzed several other parameters like the nozzle spacing, nanosolution concentration, and the nozzle-to-plate distance and noted if these parameters could increase the heat transfer rate of the twin jet impingement system on a hot aluminum surface. The researchers prepared different nanosolutions, which consisted of varying concentrations, and coated them on the metal surface. Thereafter, we carried out an X-ray diffraction (XRD) and a Field Emission Scanning Electron Microscopy (FESEM) analysis for determining the structure and the homogeneous surface coating of the nanosolutions. This article also studied the different positions of the twin jets for determining the maximal Nusselt number (Nu). The researchers analyzed all the results and noted that the flow structure of the twin impingement jets at the interference zone was the major issue affecting the increase in the heat transfer rate. The combined influence of the spacing and nanoparticle concentration affected the flow structure, and therefore the heat transfer properties, wherein the Reynolds number (1% by volume concentration) maximally affected the Nusselt number. This improved the performance of various industrial and engineering applications. Hypothesis: Nusselt number was affected by the ratio of the nanoparticle size to the surface roughness. Heat transfer characteristics could be improved if the researchers selected an appropriate impingement system and selected the optimal levels of other factors. The surface coating with the TiO2 nanosolution also positively affected the heat transfer rate.

Over the years, the world was not paying strict attention to the impact of rapid growth in plastic use. This has led to unprecedented amounts of mixed types of plastic waste entering the environment unmanaged. Packaging plastics account for half of the global total plastic waste. This paper seeks to give an overview of the use, disposal, and regulation of food packaging plastics. Demand for food packaging is on the rise as a result of increasing global demand for food due to population growth. Most of the food packaging are used on-the-go and are single use plastics that are disposed of within a short space of time. The bulk of this plastic waste has found its way into the environment contaminating land, water and the food chain. The food industry is encouraged to reduce, reuse and recycle packaging materials. A wholistic approach to waste management will need to involve all stakeholders working to achieve a circular economy. A robust approach to prevent pollution today rather than handling the waste in the future should be adopted especially in Africa where there is high population growth.

High heat generation is seen as a major issue in most mechanical and manufacturing industries, carrying with huge sub-problems. One of the possible cooling techniques is the combination of two or more passive methods, in particular for those parts with complex geometry. In this study, flow structure and heat transfer characteristics of the novel channel namely: curved-corrugated channel are numerically studied with using ZnO-water nanofluid and presence of L-shaped baffles. The influences of corrugations, baffles manner arrangement, and geometric parameters; corner angle (γ= 30°,45°,60°, and 90°) and blockage ratio (BR=0.25,0.3. 0.35, and 0.4), at different Reynolds number (8000–32000) and volume fraction of ZnO particles (0–4%) are evaluated using thermal-hydraulic performance method. The multi-phase mixture and the κ-e model are used to simulate turbulent nanofluid flows inside the curved-corrugated channels at constant temperature condition (T = 355 K). The results reveal that the formation of vortex flow and increased turbulence due to effects of corrugations and baffles can improve the heat transfer enhancement. Inline arrangement of baffle is superior to the staggered arrangement in thermal-hydraulic performance (PEC), and at lowest angle 30° provide the best PEC. Regarding the friction ratio and compared to those of a plain channel, the effect of blockage ratio is considerable as it yields a multiplier impact of the corner angle. Reducing the blockage ratio and the corner angle, i.e. 0.25 and 30°, yields to the best PEC at 1.99. New correlations for Nusselt number and friction factor for baffled curved-corrugated channel with using nanofluid are also reported.

Impinging jets are considered to be a well-known technique that offers high local heat transfer rates. No correlation could be established in the literature between the significant parameters and the Nusselt number, and investigation of the interactions between the correlated factors has not been conducted before. An experimental analysis based on the twin impingement jet mechanism was achieved to study the heat transfer rate pertaining to the surface plate. In the current paper, four influential parameters were studied: the spacing between nozzles, velocity, concentration of Nano solution coating and nozzle-plate distance, which are considered to be effective parameters for the thermal conductivity and the heat transfer coefficient of TiO2 nanoparticle, an X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) analysis were done, which highlighted the structure and showed that the nanosolution coated the surface homogenously. Moreover, a comparison was done for the experimental results with that of the predicted responses generated by the Design Expert software, Version 7 User&rsquo, s Guide, USA. A response surface methodology (RSM) was employed to improve a mathematical model by accounting for a D-optimal design. In addition, the analysis of variance (ANOVA) was employed for testing the significance of the models. The maximum Nu of 91.47, where H = S = 1 cm, Reynolds number of 17,000, and TiO2 nanoparticle concentration of 0.5% M. The highest improvement rate in Nusselt was about 26%, achieved with TiO2 Nanoparticle, when S = 3 cm, H = 6 cm and TiO2 nanoparticle = 0.5 M. Furthermore, based on the statistical analysis, the expected values were found to be in satisfactory agreement with that of the empirical data, which was conducted by accounting for the proposed models&rsquo, excellent predictability. Multivariate approaches are very useful for researchers, as well as for applications in industrial processes, as they lead to increased efficiency and reduced costs, so the presented results of this work could encourage the overall uses of multivariate methods in these fields. Hypotheses: A comparison was done for the predicted responses generated by the Design Expert software with the experimental results and then studied to verify the following hypotheses: ► Preparation of three concentrations of TiO2 nanosolution was done and studied. ► The heat transfer rate could be increased by surface coating with TiO2 nanoparticle. ► The heat transfer could be improved by the impingement jet technique with suitable adjustments.

In this study, flow structure and heat transfer characteristics of the novel channel, namely: the curved-corrugated channel, are numerically studied using ZnO-water nanofluid and the presence of E-shaped baffles. The influences of corrugations, baffles, and geometric parameters; gap ratio (GR = 0.2,0.3,0.4, and 0.5), blockage ratio (BR = 0.2,0.25,0.3, and 0.35), and pitch angle (β = 10°, 12.5°, and 15°) at different Reynolds number (8000–32,000) and volume fraction of ZnO particles (0–4%) are evaluated using thermal-hydraulic performance method. The results reveal that the formation of vortex flow and increased turbulence due to effects of corrugations and baffles can improve the heat transfer enhancement. Tested channel with baffle is superior to the other without baffle in thermal-hydraulic performance factor (THPF), and at lowest pitch angle 10° provides the best THPF. Reducing the gap ratio and increasing the blockage ratio, i.e. 0.2 and 0.35, yields the best THPF at 2.57. New correlations for Nusselt number and friction factor for baffled curved-corrugated channel with using nanofluid are also reported.

The effects of hybridization between woven mengkuang fiber/woven silk on mode II delamination (GIIC) of laminated composites were investigated by performing the end-notched flexure (ENF) test. Various configurations of woven mengkuang/woven silk layers were considered. The composite samples were prepared using hand lay-up, along with the cold press method. After fabrication, the test specimens were subjected to end-notch flexure testing for mode II delamination based on ASTM D790-03. During the test, the crack propagation was observed; the sudden drop in load meant that the sample experienced crack growth. The configuration of woven silk in between the pre-crack provided an excellent improvement in GIIC. Further addition of woven silk layers for similar configuration also yielded significant improvements in the GIIC result. The rate of critical strain energy release increases with an increase in number of woven silk layers for the configuration of silk in between the pre-crack. The scanning electronic microscopy (SEM) result shows the cross-section of the samples. The study also demonstrated that surface interaction between woven silk/epoxy/woven silk was better than woven mengkuang/epoxy/woven mengkuang lamination.

Here, the researchers carried out an experimental analysis of the effect of the TiO2 nanosolution concentration on the heat transfer of the twin jet impingement on an aluminum plate surface. We used three different heat transfer enhancement processes. We considered the TiO2 nanosolution coat, aluminum plate heat sink, and a twin jet impingement system. We also analyzed several other parameters like the nozzle spacing, nanosolution concentration, and the nozzle-to-plate distance and noted if these parameters could increase the heat transfer rate of the twin jet impingement system on a hot aluminum surface. The researchers prepared different nanosolutions, which consisted of varying concentrations, and coated them on the metal surface. Thereafter, we carried out an X-ray diffraction (XRD) and a Field Emission Scanning Electron Microscopy (FESEM) analysis for determining the structure and the homogeneous surface coating of the nanosolutions. This article also studied the different positions of the twin jets for determining the maximal Nusselt number (Nu). The researchers analyzed all the results and noted that the flow structure of the twin impingement jets at the interference zone was the major issue affecting the increase in the heat transfer rate. The combined influence of the spacing and nanoparticle concentration affected the flow structure, and therefore the heat transfer properties, wherein the Reynolds number (1% by volume concentration) maximally affected the Nusselt number. This improved the performance of various industrial and engineering applications. Hypothesis: Nusselt number was affected by the ratio of the nanoparticle size to the surface roughness. Heat transfer characteristics could be improved if the researchers selected an appropriate impingement system and selected the optimal levels of other factors. The surface coating with the TiO2 nanosolution also positively affected the heat transfer rate.

This article presents a study which sought to enhance heat transfer by employing a twin jet impingement mechanism (TJIM) and investigating the impact of the distance between the nozzles and plate on the Nusselt number (Nu) and heat transfer coefficient. This investigation was additionally based on the measurements of the heat flux temperature micro foil sensor and IR thermal imaging. A computational study of the cooling heated plate, through simulating the electronic components by the TJIM, was investigated using the RNG k-ε turbulence model. The jet-plate position was changed at the different jet-to-plate distances S = 1, 6, and 11 cm, Reynolds number = 17,000. The main flow structure, the static pressure, local and average Nus and heat transfer coefficient, were also examined. The findings have yielded new information about TJIM, and represent a new contribution about the flow and heat transfer characteristics of TJIM, and means of improving the rate of heat transfer in the passive heat transfer technique. The results of the various positions of the TJIM determined that the first model is, in fact, the best model for the heat transfer coefficient and the highest Nu, when S = 1 cm and H = 1 cm. Furthermore, the irregular distribution of the local Nu and the local heat transfer coefficient (h) on the impinged surface are due to the increase or decrease in the turbulence of flow on the measured surface.

This study investigated the energy absorption response and load carrying capability of woven natural silk/epoxy–triggered composite rectangular tubes subjected to an axial quasi-static crushing test. The rectangular composite tubes were prepared by hand lay-up technique. The tubes consisted of 12, 24, and 30 layers of natural woven silk/epoxy laminate and were 50, 80, and 120 mm long. The crashworthiness of the tubes was evaluated by measuring the specific energy absorption in quasi-static axial compression. Specific energy absorption was obtained from the load–displacement curve during testing. The failure mode of the tubes was analyzed from high resolution photographs obtained. Overall, the tube with 50 mm length and 30 layers showed the best crashworthiness among the tubes. The failure morphology showed that the specimens failed in two distinct modes: local and mid-length buckling. The triggered composite tubes exhibited progressive failure.

Cu and Zn-water nanofluid is a suspension of the Cu and Zn nanoparticles with the size 50 nm in the water base fluid for different volume fractions to enhance its Thermophysical properties. The determination and measuring the enhancement of Thermophysical properties depends on many limitations. Nanoparticles were suspended in a base fluid to prepare a nanofluid. A coated transient hot wire apparatus was calibrated after the building of the all systems. The vibro-viscometer was used to measure the dynamic viscosity. The measured dynamic viscosity and thermal conductivity with all parameters affected on the measurements such as base fluids thermal conductivity, volume factions, and the temperatures of the base fluid were used as input to the Artificial Neural Fuzzy inference system to modeling both dynamic viscosity and thermal conductivity of the nanofluids. Then, the ANFIS modeling equations were used to calculate the enhancement in heat transfer coefficient using CFD software. The heat transfer coefficient was determined for flowing flow in a circular pipe at constant heat flux. It was found that the thermal conductivity of the nanofluid was highly affected by the volume fraction of nanoparticles. A comparison of the thermal conductivity ratio for different volume fractions was undertaken. The heat transfer coefficient of nanofluid was found to be higher than its base fluid. Comparisons of convective heat transfer coefficients for Cu and Zn nanofluids with the other correlation for the nanofluids heat transfer enhancement are presented. Moreover, the flow demonstrates anomalous enhancement in heat transfer nanofluids.

In this study, lamination panels were fabricated using chopped strand mat (CSM) and woven roving fabric (WR) as reinforcement for two different types of specimens, type Eb and type Pb, respectively. By a combination of plain materials composite lamination structures were formed, with [CSM/0/90/CSM]2s as an orientation layer for the structures. In this research study, the structural panel was produced by hand lay-up technique with a combination of unsaturated epoxy and polyester resin, separately. Therefore, with this publication, a characteristic combination of chopped strand mat/woven roving fabric, are presented. The experimental work for both types of specimens were performed by bending until the structure fails. The characteristics of different materials, i. e. the chemicals used and the composite lamination structure, were studied, because there are different types of damages in the structure of composite materials, such as delamination, matrix cracking, fiber-matrix damage and fiber pull-out. Furthermore, it can affect the behavior of composite materials in the whole structure. As a result, this process contributes to failure prevention, as the capabilities of the structures are known, before it can be used for any part, component or area. It was also shown that different configuration lamination layers influence the strength properties of the composite materials.