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Erosion prediction of the solid propellent nozzle is vital for its design process. This erosion is caused by the impingement of agglomerated aluminum/aluminum oxide particles on the nozzle walls. Thus, a multi-phase numerical model is established based on the Eulerian–Lagrangian approach to model the aluminum particles burning inside the combustion chamber and simulate the mechanical erosion of the nozzle. The numerical model is validated against numerical and experimental results from the literature. Then it is simplified by eliminating the aluminum particles burning process as they do not reach the nozzle. The simplified model will be further used in modeling the agglomerates’ breakup and predicting the mechanical erosion for aluminum particles with lower surface tension. The results showed that applying the Reitz–Diwakar breakup model reduces the erosion rate by 6.2–24% depending on the injected droplets. In addition, it was found that a decrease in the erosion rate by 1–4.5% can be achieved by reducing the aluminum additive’s surface tension by 15%.

Manure waste from dairy, livestock, and poultry industries can pose significant challenges in their disposal due to their odor, nitrogen, phosphorous, and heavy metals contents, and pathogens. Existing disposal techniques like anaerobic digestion, although can provide biogas with energy output, is a slow process with significant carbon loss to CO2 and can also result in leaching. High-temperature pyrolysis can convert these wastes into syngas along with biochar which can be used for various applications. Thermochemical conversion needs to be feed-flexible, and operating it with manures from various animal sources such as poultry and dairy sectors can provide sustained operation, intensified process, and improved conversion throughput. So, we examined high-temperature co-pyrolysis of chicken and cow manures to understand the influence of their mixture fractions on the syngas components and char yield. Lab-scale semi-batch co-pyrolysis was carried out for cow and chicken manures at 900 °C with mixture fractions varying from 0 to 100%. Syngas analysis from these tests revealed the presence of synergistic enhancement of its components and in terms of syngas energy yield and carbon conversion, a 2:3 ratio of cow to chicken manure resulted in the most enhancement compared to the expected aggregate of pyrolyzing cow and chicken manures separately. This paper provides a detailed analysis of these syngas components from co-pyrolysis in comparison with separate pyrolysis to explore the advantages of blended feedstock toward an efficient, clean, and feed-flexible pathway for manure waste disposal and utilization.

The purpose of the current study is to find out the heat transfer and pressure drop phenomena of the cooling channel with dimples and guide vane and compare the results with the no guide vane dimpled cooling channel. The first leg of the cooling channel is 490 mm, and the second leg is 460 mm. The two legs relate to the 180 deg turn region. The guide vane was inserted at the bend region of the dimpled cooling channel. The study was conducted with two different guide vanes geometry at two different orientations, i.e., U-guide vane with protrusion and depression orientation and curve-guide vane with protrusion and depression orientations both experimentally and numerically. The numerical study was performed with the large eddy simulation method. The result shows that for both stationary and rotational motion, the U-guide vane with depression experiences the highest thermal performance. The friction factor is comparatively higher for curve-guide vane with protrusion under stationary motion. However, under rotation, the curve-protrusion guide encounters the highest friction factor, which is higher compared to the no guide vane cooling channel.

This study investigates the optimum operating conditions and design configurations that can optimize the power reclaimed by small hydro turbines derived by the rising water-bubble current. The rising current is generated by the compressed air introduced by the diffusers at the bottom of aeration basins of Wastewater Treatment Plants (WWTPs). While optimizing the power production, the standard oxygen transfer efficiency (SOTE) is monitored since it is a significant parameter that cannot be sacrificed in the operation of WWTPs. Using one set of turbine blades, it was found out that the highest velocity is obtained in the upper half of the water column (70% - 80%). In contrast, the lowest velocities were obtained just above the air diffuser and at the water surface. Testing started with using a single turbine (ST) to determine the location of the optimum power reclaimed at each tested airflow (1.18, 1.42, 1.65, and 1.89 L/s). Then using double turbine (DT) and triple turbine (TT) to compare their performance to the ST’s maximum power increased power reclamation. The maximum percentage of increase in power reclamation for DT is 19.59%, while it is 20.24% in the case of TT. At a commonly used airflow in WWTPs (1.42 L/s), the optimum configurations of DTs and TTs were selected to investigate the effect of having the proposed setup on the SOTE. For membrane diffusers, DTs and TTs limited the dispersion of the air bubbles in the tank, therefore, reducing the SOTE (8.3% for DT and 3.7% for the TT). The ceramic and sharp-nub diffusers were also tested versus rubber membrane ones to determine the effect of using the ceramic and sharp-nub diffusers on the power reclamation and SOTE. Ceramic diffusers neither achieve higher power reclamation than the membrane nor increases the SOTE. In contrast, sharp-nub diffusers increase the SOTE for all configurations compared to membranes, but this came into account of power reclamation, where sharp-nub diffusers cause a DT and a TT to produce less power than ST does.

Multiple jet impingement cooling plays a significant role in the leading-edge cooling of the gas turbine blade. The heat transfer enhancement with this method depends on stand-off distance, nozzle array arrangement, surface roughness, a dimpled surface, a curved surface, etc. This study has developed a numerical simulation model to investigate heat transfer and flow behavior on a dimpled surface. The comparison was made with the conventionally designed dimple and a newly designed-leaf dimple. Computational fluid dynamics plays a significant role in representing the precise flow and heat transfer behavior. This study analyzed the results based on Nusselt number, Reynolds numbers, pressure drop, friction factor, surface roughness of the target plate, and thermal performance. The hemispherical dimpled target plate shows 5–10% more efficiency than the smooth target plate. The leaf target plate shows 2–6% more efficiency compared to the hemispherical dimpled target plate

This article presents wind tunnel experimentation and uses simulations to evaluate the performance of a 14 m-rotor diameter residential-scale wind turbine at different wind speeds. The blades of the rotor baseline design are built using GOE 447 airfoil. Five different tubercle designs were applied to the blade’s leading edge. One of those designs produces more power than a baseline rotor, with an optimum power improvement of 5.5% achieved at 12.5 m/s wind speed. Furthermore, three winglet designs were added to the tip of the baseline design to investigate their influence on power production. The 90 deg, 60 deg, and 30 deg cant angles produce 5.0%, 7.9%, and 6.9% more power than the baseline design, respectively, at 12.5 m/s. Moreover, it is vital to investigate the effect of integrating leading-edge tubercles with winglets and then evaluate the influence of the combination on the aerodynamic performance and power output of the turbine model. It is found that when combining both techniques on the same blade, the improvement mechanism associated with each of them interferes with the other, leading to poor overall performance and less power in the majority of the run simulations.

Most of the available research on horizontal-axis wind turbines focuses on either lab-scale (15–60 cm rotor diameter) or commercial large-scale (80–130 m rotor diameter). The current work fills this gap because residential-scale turbines will be one of the key technologies during the next ten years. The current administration promotes dependence on renewables to cut carbon footprint. Therefore, the present work runs wind tunnel experimentation and performs 48 numerical simulations to evaluate the performance of a residential-scale wind turbine with a blade generated from GOE 447 airfoil at three wind speeds (7.5, 12.5, and 17.5 m/s). Three different vortex generator designs were tested when added on the suction side of a 7-m blade. Two of those designs produced more power than a baseline rotor does (7.2% and 10.9% more power than the baseline rotor were achieved at 12.5 m/s wind speed). Furthermore, three winglet designs were added to the baseline design to investigate their influence on power production. The 90 deg, 60 deg, and 30 deg cant angles produce 5.0%,7.9%, and 6.9% more power than the baseline design.

The present investigation represents the rotational effect on gas turbine blade internal cooling with a uniform heat flux of 2000 W/m2 at the bottom wall. The experiment was conducted with three different rpms, such as 300 rpm, 600 rpm, and 900 rpm, with Reynolds number (Re) ranging from 6000 to 50,000 with a two-pass cooling channel. The numerical investigation was conducted with the large eddy simulation (LES) technique to understand the rotational flow behavior of the cooling channel. Four distinct arrangements of dimpled cooling channel surfaces were considered with two different dimple shapes, i.e., partial spherical and leaf. It is found that the rotation effect, dimple arrangement, and design have significant influences on heat transfer. Results indicated that the partial spherical 1-row dimpled surface experienced the highest heat transfer coefficient and pressure drop. In contrast, the leaf-shaped dimpled cooling channel experienced the highest thermal efficiency.

Non-uniformity of the exit flow temperature represents one of the significant damages to gas-turbine components, particularly turbine blades. This may occur in the course of gas-turbine operation. This paper aims to provide passive techniques by modifying the combustor design rather than changing the flow parameters to improve the thermal uniformity and turbine blades to reduce thermal stresses and increase turbine blades’ life span. An acceptable agreement between the numerical and experimental results has been achieved, and the agreement includes the velocity and temperature profile. Four different angles have been tested numerically and experimentally with a maximum error of 5% at two different Reynolds numbers. Designing the outer combustor surface with a 45-deg angle bend can give a more uniform temperature distribution of 37% higher than the basic design with only a 0.5% higher pressure drop.

The mass angle distribution shows a strong correlation between mass and angle when quasifission events are dominant. Therefore, as long as quasifission events are dominant, the mass angle distribution is characterized in that diagonal correlation appears. This diagonal correlation could not be reproduced in our previous model that is before introducing $${{f}_{{{\text{ina}}}}}$$ and $$\gamma _{t}^{0}$$ model parameters. In this study, we clarify the indeterminate parameters included in the model to reproduce the diagonal correlation appearing in the mass angle distribution in the 48Ti + 186W reaction system. As a result, $${{f}_{{{\text{ina}}}}}$$ and $$\gamma _{t}^{0}$$ of model parameters found to be key parameters for MAD. it was also found that the balance between $${{f}_{{{\text{ina}}}}}$$ and $$\gamma _{t}^{0}$$ parameters values is important for the strong correlation between mass and angle.

For the success the synthesis of superheavy elements $$Z>118$$ , it is indispensable to clarify the fusion–fission mechanism, which includes a role of the nuclear structure of colliding nuclei and the deformation in the fusion process. We develop the dynamical model to estimate the probability to produce new superheavy nuclei. To approach Island of Stability and synthesize new elements, we propose the new idea, which takes advantage of the shell structure in fusion and fission process.

In this work, the effect of the inner opening ratio on the J-shaped airfoils aerodynamic performance was studied and documented for symmetrical airfoils. Three different airfoil thicknesses were investigated: small (NACA0008), medium (NACA0015), and large (NACA0024). For each airfoil thickness, effects of three inner opening ratios were analyzed: one-third, one-half, and two-thirds. The performance of each opening ratio was compared with the performance of the solid airfoil “zero opening ratio” for different angles of attack between 5 deg and 20 deg. All designs were simulated using the computational fluid dynamics (CFD) technology against experimental results for solid NACA4412 airfoil in the University of Wisconsin-Milwaukee (UWM) wind tunnel facility and other published experimental data. It was found that large eddy simulation yields accurate solutions with a smaller number of mesh cells compared to the k–ω turbulence model but with much longer computational time. The lift-to-drag ratio for all studied airfoils has a maximum value for solid airfoils compared to those equipped with openings. For airfoils equipped with 00.00% opening ratio “solid,” NACA0015 airfoil has the maximum lift-to-drag ratio. Furthermore, it was found that NACA0008 equipped with a 33.33% opening ratio has the best performance of all studied J-shaped airfoils.

Energy savings and emission reductions are essential for internal engines. Turbocharger is critical for engine system performance and emission. In this study, the engine simulation program was used to systematically optimize the engine turbocharger system performance. The velocity ratio concept was used in the engine simulation program to consider the performance impacts of the wheel diameter ratio between compressor and turbine. An integral consideration for both compressor and turbine was proposed to design the new turbocharger. An optimization process was used to design the compressor. The performance and mechanical integrity assessments for final designs by using computational fluid dynamics (CFD) and finite element analysis (FEA) solvers were reported in this paper. The optimized compressor wheel has some distiguished features comparing with conventional designs. In this design, the splitter is not located at the middle between the two main blades; the compressor wheel exit diameter at shroud is larger than exit diamerer at the hub. The new compressor was tested on both gas stand and engine. The numerical results are fairly agreed with gas stand tests. The tests showed about 1.2% of the engine BSFC reduction without sacrificing the emission and cost. This study demonstrated that a systematic method in simulation and a compressor design optimization process could optimize the engine system and improve the engine performance.

Investigating the mechanical erosion of the solid rocket motor convergent-divergent (C-D) nozzle is essential to overcome its development barriers. Consequently, the break-up mechanism of the aluminum oxide agglomerates was studied to determine the influence of the exhaust gas flow acceleration during the flight. Water and air flows were used as a substitute for aluminum oxide and exhaust gases. Experiments were conducted at different water flowrates and constant air velocity, where the results were used to validate a numerical model. The results revealed an excellent acceptance between the numerical, the experimental data (6–19%), and the effect of increasing the water flowrate on the break-up mechanism. The validated numerical model was further used to study the airflow acceleration impact on the break-up process. It was found that applying acceleration to the airflow subjects the water surface to rapid and sudden changes in the relative velocity between the gas and liquid, thus separating more water fragments from the primary liquid. In other words, it enhances the break-up process by reducing the average diameter with a range from 6.5% to 9% compared to the no-acceleration case and increasing the average droplets’ number (8.5–17%).

Self-healing wind turbine blades can reduce costs associated with maintenance, repair, and energy compensation. Self-healing is the ability to sustain and recover from damage autonomously. We discuss the efforts made to optimize the self-healing properties of wind turbine blades and provide a new system to maximize this offset. This system utilizes vacuum-assisted resin transfer molding (VARTM), and 3D printed templates to imprint a vascular network onto a single glass fiber-reinforced polymer (FRP) sheet. This imprinted layer is infused with Grubbs first-generation catalyst and filled with dicyclopentadiene (DCPD) which is then sealed using plastic sheeting. The sealed imprint layer is embedded into a larger multilayer FRP prior to VARTM. After VARTM, the completed multilayer FRP is fully capable of self-healing microcracks. Three-dimensional printed templates with square grid and hexagonal patterns were used to evaluate how differences in DCPD distribution affect overall recovery. Three-point bending tests were performed to obtain the maximum flexural strengths of the FRP samples before and after self-healing to evaluate recovery. Overall, with the imprint layer method, the catalyst was focused in one area of the complete FRP, reducing the amount of unused catalyst present in the FRP. Also, the samples created using the imprint method were able to achieve a maximum average recovery of over 200% and a storage efficiency of 100%.

This study targets one of the major energy consumers in the U.S. It suggests a new mechanical system that can recover a portion of the energy in Wastewater Treatment Plants (WWTPs). The proposed system entails a hydro-turbine installed above the air diffuser in the aeration tank to extract the water-bubble current’s kinetic energy and converts it to electricity. Observing the optimum location of the turbine required multiple experiments where turbine height varies between 35% and 95% (water height percentages above the diffuser), while varying the airflow between 1.42 L/s (3 CFM) and 2.12 L/s (4.5 CFM) with a 0.24 L/s (0.5 CFM) increment. Additionally, three water heights of 38.1 cm (15″), 53.4 cm (21″), and 68.6 cm (27″) were considered to study the influence of the water height. It was noticed that the presence of the system has an adverse effect on the standard oxygen transfer efficiency (SOTE). Therefore, a small dual-blade propeller was installed right above the diffuser to directly mix the water in the bottom of the tank with the incoming air to enhance the SOTE. The results showed that the maximum reclaimed power was obtained where the hydro-turbine is installed at 65–80% above the diffuser. A reduction of up to 7.32% in SOTE was observed when the setup was placed inside the tank compared to the tank alone. The addition of the dual-blade propeller showed an increase in SOTE of 7.27% with a power loss of 6.21%, ensuring the aeration process was at its standards.

The study presents the investigation on heat transfer distribution along a gas turbine blade internal cooling channel. Six different cases were considered in this study, using the smooth surface channel as a baseline. Three different dimples depth-to-diameter ratios with 0.1, 0.25, and 0.50 were considered. Different combinations of partial spherical and leaf dimples were also studied with the Reynolds numbers of 6,000, 20,000, 30,000, 40,000, and 50,000. In addition to the experimental investigation, the numerical study was conducted using a large eddy simulation (LES) to validate the data. It was found that the highest depth-to-diameter ratio showed the highest heat transfer rate. However, the deepest dimpled channel shows the highest pressure drop, which affects the overall thermal performance of the cooling channel. The results showed that the leaf dimpled surface is the best cooling channel based on the highest Reynolds number's heat transfer enhancement and friction factor. However, at the lowest Reynolds number, partial spherical dimples with a 0.25 depth-to-diameter ratio showed the highest thermal performance.

In this study, the internal cooling channel was investigated without any bend. Smooth surfaces and dimpled surfaces were investigated using the different combinations of connecting circular and rectangular holes. The computations were performed using the large eddy simulation (LES) model for Reynolds (Re) numbers from 10,000 to 50,000. A total of six different connecting holes were investigated with a smooth and dimpled surface. A partial spherical dimple with two circular holes showed the highest heat transfer, but it has a higher pressure loss penalty. Even though the leaf dimpled surface with the rectangluar holes indicated a little low heat transfer, it represents the highest efficiency at higher Reynolds numbers because of the low-pressure drops.

Computational fluid dynamics had shown significant development in software capability and hardware during the last two decades. It has become an essential tool in various product development stages and is used actively in advanced research technology. Renewable energy varies from traditional to new resources such as biomass, fuel cells, water, wind, and solar. These renewable sources are playing a significant role in electric generation, and both energy producers and consumers are demanding more deployment of these sources. There is a great advantage in using numerical simulation methods for innovative renewable technologies such as wind energy, biomass, solar power, hydropower, gas and steam turbines, fuel cells, tidal, wave, and many others. CFD analysis provides an additional resource for these innovative renewable energy sources to predict results that can save time and money and reduce physical prototyping and testing resources. This paper intends to outline and discuss all CFD applications in renewable energy sources, helping understand these methods’ advantages and usage.

This paper presents different thermochemical conversion processes on different biomass species. The results show it is recommended to use the lowest heating rate to allow a quasi-equilibrium state through slow heating, hence avoiding measurement errors. Thermal degradation of the three main components of the chicken manure was obtained. The initial results show that for the slow heating rates, 5 °C/min, the thermal degradation of the cow manure is different compared to that one obtained from chicken manure. The Hemicellulose decomposition took place at 250 and 300 °C for the chicken manure and cow manure, respectively. The Cellulose decomposition was started at 300 °C for chicken manure and 470 °C for cow manure. Rice husk, the peak of the Pyrolysis of rice husk, is less distributed than the Pyrolysis of chicken manure due to the absence of Hemicellulose and less Lignin content. For CO2 gasification, the chemical reactions, for all different heating rates tested, were endothermic. Consequently, the energy must be supplied in terms of heating to sustain the reaction, while air gasification was exothermic, which means that the reaction can be sustained without external heating where the self-ignition was observed between 450 and 600 ℃. In addition, it was observed that carbon dioxide had the most complicated mechanism with four stages. CO-Pyrolysis, results show the 40% RH-60%CH decreasing the activation energy by 12% compared to Chicken manure. In addition, an increase in the mass conversion by more than 3% was achieved. The 40% CM-60% CH shows a positive result in terms of keeping an exothermic reaction over the co-Pyrolysis process.

Air compressors, a key fluid power technology, play an essential role in industrial plants and office buildings, hospitals, and other types of facilities. The efficient use of the air compressor is crucial. By controlling unnecessary inefficiencies, high energy consumption can be reduced. This study aims to provide energy and exergy analysis on air compressors for different industries. Detailed case studies were also analyzed. The case study focuses on the energy and exergy analyses of the compressed air system of foundry industries. The results indicate that applying the six improvement recommendations yields significant amounts of energy and cost savings and significant improvements in the system's overall performance. The payback periods for different recommendations are economically feasible and worthwhile to use. The suggested improvement methods can provide cost savings with a low payback period.

Using fossil fuels as the primary way to generate electricity causes a significant effect on the environment. In 2019, more than 64% of the electricity in the United States of America was generated using fossil-fuel resources, while renewable energy (RE) resources contributed to only 17% of the U.S. electricity generation for the same year. Due to the complex terrain distribution of many states in the U.S., a massive opportunity of utilizing RE resources in rural and remote areas can reduce the cost of electrical grid installation for such areas. In this study, a typical residential building with an average energy utilization of 30.25 kWh/day with a demand peak of 5.34 kW was considered a case study in each state to optimize a hybrid RE system and find the best alternative electrical grid system. This study presents the best configuration between solar and wind energy with different types of energy storage. It was discovered the photovoltaic (PV) solar panels—diesel generators with battery best services in all states. The daily radiation and diesel prices substantially affect the levelized cost of energy (COE) values in each state.

Objective: Adolescents involved in prostitution are exposed to traumatic experiences with long-term adverse effects including symptoms of posttraumatic stress disorder (PTSD). Maltreated children tend to perform poorly on tasks of visuospatial orientation. We hypothesized that adolescents who had been involved in prostitution would have weak visuospatial skills and that those with a diagnosis of PTSD would have worse visuospatial skills than those without a diagnosis of PTSD. Method: Due to academic concerns, comprehensive neuropsychological assessment was conducted in a community mental health center with 22 adolescents (21 female and one trans to female) who had been involved in prostitution. Visuospatial skills were measured using the Rey-Osterrieth Complex Figure Test (ROCF). IQ ranged from 72 to 112 (M = 85.4, SD = 13.27). Sixteen out of the 22 participants were diagnosed with PTSD. Results: Adolescents involved in prostitution scored significantly lower on the copying trial of the ROCF (M = 24.2, SD = 7.89) than the normative sample (M = 33.6, SD = 2.98), t = -5.60, p Conclusion: The findings suggest that adolescents who experienced the trauma of prostitution may have deficiencies in visuospatial functioning, regardless of PTSD diagnosis. Thus they may distort environmental information, leading to poor decision-making.

This paper highlights the expected versus actual outcomes of 152 energy assessments that were performed between 2011 and 2020. The 1317 energy-assessment recommendations (ARs) are grouped into eight categories. This study adopted four measures per each category of recommendations: annual electricity savings, annual gas savings, annual cost savings, and annual CO2 emission reduction. The first part of the analysis compares the expected to the actually implemented values of the measures applied to each recommendation’s category. It was found that the percentages of the actual to the expected electricity, gas, and cost savings are 26.6%, 11.4%, and 17.1%, respectively, while the percentage of the actual to the expected CO2 reduction is 22%. Moreover, the second part of the analysis presents each category's implementation rate and the reasons for rejecting the unimplemented ARs. Cash flow and expensive initial investment resulted in rejecting 25% of ARs. Furthermore, the study proposes techniques and strategies to increase ARs’ implementation rate and improve private energy services companies’ implementation rate. Finally, exergy analysis is added to show the improvement that energy assessment achieves regarding exergy and exergy efficiencies of different industrial applications.

The gas turbine engine's extreme conditions need a robust design to produce efficient energy and for reliable operation. Flow and thermal analysis are essential for complex aerodynamic and thermodynamic interaction during turbine performance. There is a need to understand and predict the temperature to make the gas turbine engine efficient. This paper will outline the numerical methods applied for primary cooling methods in gas turbine blades. These include impinging leading-edge cooling, internal cooling in the midsection, and pin fin in the trailing edge. The main objective of this paper is to understand the numerical research done on improving gas turbine cooling. The emphasis will be on understanding the present computational fluid dynamics (CFD) techniques applied for gas turbine cooling and further development. This paper briefly outlines the new conjugate heat transfer–based CFD modeling techniques that have evolved over the years due to recent computing power development.

The primary objective of this study is to achieve net-zero energy (NZE) wastewater treatment plants (WWTPs) by utilizing energy efficiency opportunities (EEO), combined heat and power (CHP) systems, and other renewable energy (RE) sources, e.g., solar, water, and wind powers. This study discusses an innovative energy solution for WWTPs in the United States, and one of the WWTPs with a flow capacity of 1.5 million gallons per day (MGD) was selected as a case study. An optimization tool, Hybrid Optimization of Multiple Energy Resources (HOMER) software, is used in this study to find the best energy system configuration to run the system. An energy audit for one WWTP was conducted in early 2020 and the report is used to do this study. The proposed EEOs were able to reduce WWTP energy consumption by about 11%. The excess anaerobic digester gas was utilized in a CHP system to cover about 42% of the facility’s consumption. Also, 3% of the utility energy consumption can be claimed by microturbines in the aeration tanks. Another two renewable energy systems, solar photovoltaic (PV) with 29% and water turbines with 15%, contribute to covering 100% of the WWTP energy consumption and achieving an NZE WWTP.

By adopting different methods to the inlet of a zooplankton olfactometer, the current study investigates the effect of the energy of chemical flow on the Gnathiid isopod crustaceans predicted behavior. These are mobile external parasites of fishes that have a significant impact on the health of their hosts. They rely at least in part on olfactory cues to find the host fish. To better understand host-finding dynamics in these parasites, a study was conducted with the simulations as a blueprint for developing a 3-dimensional test apparatus similar to what has been used for studying olfactory orientation in insects. The simulated olfactometer has four legs, each leg forming an inlet where fluids are introduced into the flow domain. There is one outlet at the center of the device. A mixture of water and chemicals is presented by applying a multi-component system. The shear and chemical concentration distribution were conducted to see how fluid physics plays a role in creating a chemical landscape. Computational results show distinct regions separated by high chemical concentration gradients when introducing chemicals from one leg. Changing the fluid inflow from one common inlet to three inlets shows that the chemical distribution exhibits steeper gradients than the typical inlet case, depicting that the gradual chemical concentrations can drive the animal toward the target faster. The best behavior that gives higher chemical gradients is obtained through the study when using three sub-inlets and Schmidt number between 3 and 10.

This study aims to better understand the aluminum oxide agglomerates breakup mechanism, consequently determining the best solution for the solid rocket motor (SRM) nozzle erosion problem. Two-phase air-water flow experimental investigation was conducted as a substitute for liquid aluminum agglomerates and exhaust combustion gases. The results show that increasing the exhaust air velocity enhances the droplet's breakup tendency to reduce the average diameter and increase droplet numbers per the testing channel volume. Numerical models were constructed and validated using the experimental results. The percentage error in the droplets’ average diameter and the number is between 6 and 15% and 8 and 18%, respectively. Furthermore, the effect of reducing the liquid surface tension was studied. The results showed that it facilitates water bodies’ separation from the interface surface, because of the reduced bounding forces between surface’s molecules, which enhances the breakup process (0.5–17% increase in the droplets’ average diameter and 4–100% increase in its number) and reduces the droplets impact on the nozzle walls, hence reducing the SRM nozzle erosion problem.

In the dilution section of the gas turbine, the flow and thermal mixing between the cold radial jets and hot mainstream is always a matter of interest to generate a consistent thermal profile, extending the longevity of the turbine blades. Multiple researches explored the topic experimentally and numerically, and new designs have been evaluated, including a central streamlined body with swirlers inside the dilution zone. Moreover, the dimensional aspects (diameter, length, and position) of the streamlined body can help in generating more uniform thermal profiles, but with the cost of increased pressure drop. Various design iterations are needed to be tested and assessed based on minimizing the contradicting uniformity number and pressure drop. Such a process is time and resources consuming if not wisely managed. The paper proposes a solution for the current problem by the integration of the “Design of Experiment/Optimization Algorithms” generator with the computational fluid dynamics solver. The outcomes from three different algorithms (ULH, MOGA-II, and HYBRID) are statistically analyzed to understand inputs-outputs correlations, develop response surface methodology, and help in finding the optimal designs. The suggested HYBRID optimization provided a better optimal curve with improvements of 69% and 15% in the thermal uniformity and pressure drop, respectively. The correlation coefficients stressed on the importance of the diameter as the highest influencer with inverse and direct correlations with uniformity and pressure drop, respectively. Finally, the Kriging response surface model enabled more optimal designs and a better understanding of the effective ranges of the three inputs.

Energy audits can identify energy consumptions, energy costs of the facility and evolve to develop measures to maximize efficiency, optimize supply energy, and eliminate waste. This paper investigates the potential energy savings at 20 different industrial sectors with 152 assessments for various facilities in Wisconsin, USA. On average, eight energy recommendations were suggested and applied in each facility. This paper provides a detailed guideline for each industry in terms of eight different energy categories: heating, ventilation, and air conditioning (HVAC) systems, heat recovery systems, electrical demand management, and utility bills, motors, compressors, waste management, and productivity enhancement, lighting, besides building envelope. In total, the energy savings were as follows: 98 million kWh in the shape of electricity, 561 billion British thermal units (BTUs) gas savings, 44 million gallons water savings, and 2-million-pound solid waste savings. Based on these savings, a 100-thousand-ton reduction in carbon dioxide emissions was obtained.

Upgrading the aeration basin technology can improve the oxygen transfer efficiency (OTE), while keeping the energy consumption at its minimum level. Therefore, this paper introduces a new idea of installing micro-propeller turbines in the aeration basin of a wastewater treatment plant (WWTP) to extract power from the high-velocity location in the water column. This extracted power can be used to operate a mixer at the top of the membrane to induce the mixing in that region, which will drive the less oxygenated wastewater into the water column. The rest of the extracted power will rotate microturbine rotors for electric power generation. By applying the proposed microturbines to the 13 audited facilities, it was demonstrated to achieve a gross annual energy-savings of 3,836.9 MWh, a gross annual cost-saving of $260,497, and total CO2 emissions that would be reduced by 2,714 metric tons/year. Generally, the addition of the proposed microturbines can save up to 15.7% of the annual plant electricity consumption (1.3–12.8% of the plant annual electricity bills).

The higher firing temperature reflects the higher efficiency of the gas turbine. However, using higher temperatures is limited as it may cause a rupture, bending, or failure of the turbine blades. Hence, the development of an effective internal cooling system of the gas turbine blade is essential. At the same time, it is necessary to ensure the lowest possible penalty on the thermodynamics performance cycle. Researchers are working over the years to find out the efficient cooling channel design with high transfer while the lowest pressure drop. They ran several cases both numerically and experimentally. This paper reviews the published research in the various methods of gas turbine internal cooling, such as using rib turbulators, dimples, jet impingement, pin fins, and guide vane, of the gas turbine blade.