A study was conducted in a broiler house belonged to Poultry research station - national Board of Agri. Research Iraq -Baghdad. The purpose of the study was to investigate how the rearing system affects the litter chemical components, hence how these elements impact the air pollutants in the poultry house especially ammonia, (particulate Matter) PM10 and PM2.5 µm. The litter chemical components include Ph, dry matter, moisture, ash, organic matter, nitrogen and crude protein. 608 birds were distributed into 16 pens inside the poultry house under varying conditions: first Litter/padding deep 5 vs 7 cm. second, spatial distribution, or in other word bird location near air inlet vs. exhaust outlet, third was stocking density (7 birds /m2 vs. 12 birds/ m2 ). The Amonia gas was quantified by the multiple gas monitoring detector S360 along with BENETECH-GM8806-Ammona-Gas-Detector as back up device. The pm 10 and 2.5 µm were quantified using multiple gas monitoring and detector S360.THC-4 temperature and humidity data logger was used to log the data. The findings demonstrated that not all the litter's chemical constituents were impacted. The only factor that had an impact on the parameters of dry matter, moisture, ash, and organic matter was the stocking density. The results also showed that the ammonia level was not detectable during all 5weeks of age. The pm10 and 2.5 µm were very high in the beginning of rearing period with lower rates in between because of using gaseous brooders in the beginning of the rearing period and later on due to the high levels of dust particles resulting from the ground feed that was provided to the birds more than once daily , because the birds grow in age and became larger in size hence the mechanism of its wings interacting with the litter and feed became also stronger during the last stages of rearing.

In shale gas extraction, solid particles such as fracturing proppants cause erosion in production and transmission pipelines. Cyclone desanders are widely used for gas–solid separation, but high-velocity sand-laden fluids frequently induce equipment failure, leakage and safety risks. Therefore, research on erosion and protective measures is essential. This study focuses on the desander at the M shale gas wellhead, where wall thickness was measured at three monitoring points to determine erosion rates. A CFD-based numerical erosion model for the cyclone desander was developed using ANSYS Fluent within the ANSYS Workbench 19.2 environment (ANSYS, Inc., Canonsburg, PA, USA). The model was validated by comparing simulation results with field data, revealing the distribution patterns of the velocity field, pressure field, and erosion rate. The study analyzed the impact of nine factors on desander erosion: inlet aspect ratio, cylinder radius, cone length, dust discharge port diameter, exhaust port diameter, particle size, particle concentration, inlet velocity, and operating pressure, clarifying the erosion variation patterns for each factor. SPSSAU V25.0 (Beijing Qingsi Technology Co., Ltd., Beijing, China) was employed to analyze the significance of these nine factors, identifying six significant influencing factors: inlet aspect ratio, cylinder diameter, dust discharge port diameter, particle size, particle concentration, and inlet velocity. Subsequently, response surface analysis was performed using Design-Expert 13 (Stat-Ease, Inc., Minneapolis, MN, USA) to obtain the relationship between the factors and their impact on maximum erosion, leading to the establishment of a predictive model for the maximum erosion rate. In addition, geometry optimization, local wall thickening, coating protection, material selection, and bionic rib structures were discussed as erosion-mitigation strategies. The optimized geometry reduced the erosion rate at the inlet and dust discharge outlet by 20.4% and 21.8%, respectively, while the bionic rib structure reduced the maximum erosion rate by 58%.

As one of the most promising new materials in the field of materials science, high-entropy alloys (HEAs) have attracted widespread attention due to the unique structure, exceptional properties and engineering performance, and complex composition. The CoCrFeNiZr0.5 eutectic high-entropy alloys (EHEAs) exhibits excellent high-temperature thermal stability, ductility, creep resistance, and corrosion resistance, demonstrating great potential for applications in marine equipment. This paper explores the engineering feasibility of electrical discharge machining (EDM) of CoCrFeNiZr0.5 EHEAs and investigates the EDM of micro-holes using a hollow copper electrode on a CNC EDM drilling machine under various machining parameters, including different gap voltage, pulse-on time, pulse-off time, and pulse amplifier settings. The effects of these parameters on the inlet diameter, outlet diameter, and recast layer of the micro holes are analyzed. The optimal micro-hole machining parameters are determined by comprehensively considering machining efficiency and electrode wear: gap voltage of 33 V, pulse-on time of 3 μs, pulse-off time of 1 μs, and pulse amplifier output of 3 A. Adopting the parameters to process a button ingot sample with a depth of 5 mm, it was found that the machining speed is 7.79 mm/min and the electrode wear is 1 cm. This research renders the foundation for further development and engineering application of CoCrFeNiZr0.5 EHEAs in the context of high-value material design and manufacturing.

Electrochemical additive manufacturing-based cold plate with distributed inlet nozzles and outlet slots for high-power-density electronics cooling

Effects of inlet–outlet configurations on thermal–hydraulic characteristics of a petaloid micropin-fin heat sink

Moisture in run-of-mine coal significantly reduces its calorific value, increases transportation cost, and causes operational difficulties in furnace systems. This paper presents the design, fabrication, and experimental evaluation of a laboratory-scale Coal moisture remover that employs forced convective thermal drying. The system integrates four core subassemblies: a motorised conveyor belt for continuous coal feeding, nichrome/FeCrAl alloy electric resistance heating coils as the heat source, a suction fan running at 2900 RPM to drive heated airflow through the coal bed, and three temperature sensors positioned at the inlet duct, drying zone, and outlet to monitor the real-time thermal profile. The prototype was designed with low-cost, locally procurable components and standard workshop fabrication processes, keeping total outlay well below commercially available industrial dryers. Experimental trials conducted at varying coil power settings and belt feed rates indicate an expected moisture reduction of 50% to 70% relative to initial moisture content, with a corresponding improvement of 10%– 20% in effective calorific value. This work demonstrates a practical, affordable, and fully instrumented drying platform suitable for laboratory research, small industrial units, and educational settings.

This study clarifies the hydrological cycle structure of the Pingjiang underground river system using hydrogeological mapping (1:50,000), tracer tests, automated groundwater monitoring, and RTK surveys. The obtained results indicate the following: (1) The Pingjiang underground river basin covers an area of 110.66 km² and consists of five tributary conduits, forming a dendritic-network composite structure dominated by unilateral recharge; (2) The threshold rainfall required to generate surface runoff is around 20 mm, which may exceed even 50 mm under prolonged drought conditions. When the daily rainfall exceeds 50 mm, the discharge at the underground river outlet increases significantly. The karst conduit system demonstrates a pronounced flood attenuation effect, capable of delaying the flood peak by up to 21 h. (3) The flow dynamics at the sinking stream inlet and underground river outlet exhibit strong consistency. The discharge at the outlet ranges from 0.35m3/s to 25.57m3/s, displaying flashy characteristics. The Bujing sinking stream inlet contributes 18.86% of the annual runoff to the underground river. (4) The underground river has a baseflow runoff modulus of 3.21 L/s·km2 during the dry season.

Abstract This study experimentally investigates the thermal–hydraulic performance of ultra-confined two-phase jet-impingement cooling using a distributed inlet–outlet nozzle manifold, a configuration that has received limited attention in prior work. It addresses a critical knowledge gap by providing the first experimental characterization of a confined two-phase distributed inlet–outlet jet architecture operating at an extreme confinement height of 0.33 mm (h/d = 0.66), representative of practical chip-level cooling constraints. Simultaneous measurements of critical heat flux (CHF), pressure drop and local impingement cavity pressure enable direct evaluation of thermal–hydraulic tradeoffs under strong confinement. Experiments were conducted with the low-GWP refrigerant R1233zd(E) over flow rates from 0.15 to 1.25 LPM and jet-array densities corresponding to non-dimensional jet-to-jet spacing of s/d = 4.0–10.0. The results show that CHF and thermal–hydraulic efficiency are governed by jet-array density in ultra-confined regime, where liquid momentum, vapor evacuation, and confinement-induced flow resistance are tightly coupled. Maximum CHF values approaching 270 W/cm2 are achieved at ultra-low pumping powers below 0.4 W. Direct impingement cavity pressure measurements reveal a transition in the CHF-limiting mechanism from thermally dominated dryout at low flow rates to hydrodynamically constrained operation at higher flow rates. A scaling relationship linking CHF to jet Reynolds number and jet-array spacing is established, providing quantitative design guidance for high-performance ultra-confined two-phase jet-impingement cooling systems.

Abstract The polysilicon reduction furnace is the key production equipment in the improved Siemens process. Variations in the internal flow velocity and temperature distribution significantly affect the reduction reaction and the deposition quality of polysilicon. In this work, the inlet velocity, silicon rod temperature, and inlet–outlet configuration of the furnace are selected as major influencing factors. A three-dimensional model of the furnace is built in NX, and simulations of the internal flow and temperature fields are conducted using Fluent. By comparing the optimal inlet velocity, silicon rod temperature, and structural configurations, this study provides guidance for improving the operational performance of industrial polysilicon furnaces.

Abstract Aims Spinal cord ischaemia (SCI) and paraplegia may follow aortic aneurysm (AA) repair due to disruption of spinal cord blood flow. Current predictive tools are unreliable, limiting perioperative risk assessment. We aimed to develop an in-silico ‘digital twin’ of the aorta and spinal cord branches to characterise haemodynamic changes after AA repair. Methods CT angiograms obtained before and after endovascular thoracoabdominal aneurysm repair were reconstructed in SimVascular. Pulsatile flow simulations used patient-specific inlet and three-element Windkessel outlet boundary conditions. Haemodynamic changes after stent coverage of intercostal and lumbar arteries were evaluated with further assessment of surface metrics: time-averaged-wall-shear-stress (TAWSS), oscillatory-shear-index (OSI), relative-residence-time (RRT), and endothelial-cell-activation-potential (ECAP). Results Two patients with type IV thoracoabdominal AA repairs using non-customised 4-branched devices were modelled: one remained well, the other developed paraplegia. In the uncomplicated case, spinal cord flow fell 51.9% after exclusion of 19 branches, with increased TAWSS (+5.2%), reduced RRT/ECAP, and minimal OSI change. In the paraplegic patient, flow fell 66.1% after exclusion of 15 branches. The uncomplicated patient showed redistribution of flow away from the spine, with modest increases in leg (+6.1%), reno-visceral (+5.9%), and supra-aortic (+6.0%) vessels. Visceral arteries had the highest TAWSS and lowest RRT/ECAP, while leg arteries had the lowest TAWSS and highest RRT/ECAP. Conclusions This proof-of-principle study demonstrates the feasibility of predicting spinal cord haemodynamics after aortic repair using open-source software and routine imaging. Expansion to larger cohorts could yield a clinical decision-support tool to stratify SCI risk and address this unmet need.

This study presents a comparative parametric investigation of the combined effect of phase change materials (PCMs) integrated into brick walls and natural ventilation strategies on indoor thermal comfort under the arid summer climate of Oum El Bouaghi, Algeria. A CFD analysis using ANSYS Fluent evaluated four PCMs (hexahydrate, n-hexadecane, n-eicosane, and n-octadecane) and three ventilation configurations with different inlet–outlet arrangements. The PCM performance was analyzed over seven consecutive July days using measured outdoor temperatures as boundary conditions, while ventilation scenarios were assessed during representative hot days to reduce computational cost. Thermal performance was assessed through indoor air temperature, wall heat flux, effective draft temperature (EDT), and the field synergy angle between velocity and temperature-gradient vectors. Although n-hexadecane exhibited the highest instantaneous heat absorption and the lowest internal surface temperatures during peak periods, its early phase transition limited sustained thermal regulation. In contrast, n-octadecane, with a melting range of 301–302 K, provided more stable and prolonged temperature control, making it the most suitable PCM among the investigated candidates when considering both thermal stability and indicative material cost. A parametric thickness analysis showed that increasing PCM thickness up to 10–15 cm led to diminishing thermal returns, achieving up to 52% reduction in daily integrated heat flux compared to the brick-only reference wall under July conditions. However, this range represents an upper-bound performance scenario; from an engineering feasibility perspective, thinner PCM layers (e.g., 5–10 cm) may provide a more practical balance between constructability and thermal benefit. The ventilation configuration with a bottom inlet and top outlet on opposite walls yielded the most stable indoor conditions due to improved air circulation. The study also introduces EDT and a synergy parameter to quantify the interaction between heat transfer and ventilation. Overall, combining PCM-enhanced walls with climate-adaptive ventilation demonstrates significant potential for reducing cooling demand and improving sustainable building performance in hot climates.

Explainable rule-based steam trap leakage detection from thermal images using inlet–outlet contrast analysis

Purpose The purpose of this study is to reveal the influence mechanism of centrifugal inertial effect on the dynamic tracking stability of spiral groove dry gas seal (S-DGS) and to explore the interaction between the special effects of the flow field under high-parameter conditions. Design/methodology/approach The real-gas behavior of carbon dioxide (CO2) is expressed by the Virial equation, and the occurrence of exit choked flow is determined when the exit velocity reaches the sound speed. Perturbation and finite difference methods are used to calculate dynamic gas film characteristic coefficients, and then an axial dynamic model for S-DGS is developed considering centrifugal inertia, choked flow and real-gas effects, which is analytically solved to obtain the axial tracking performance of CO2 S-DGS. Findings The centrifugal inertia effect suppresses the axial tracking capability of the stationary ring in pumping-inward S-DGS, while enhancing it in pumping-outward S-DGS. The real-gas effect primarily influences the inertia effect through gas density, and affects the choked flow effect via dynamic gas film characteristic coefficients. The choked flow effect impacts the real-gas effect through the inlet–outlet pressure differential and affects the inertia effect via dynamic gas film thickness. The inertia effect mainly influences both the real-gas effect and the choked flow effect through gas flow resistance. Originality/value Divergent impacts of centrifugal inertia effect on axial tracking performance of two S-DGSs are revealed, and the complex interaction mechanisms of three special effects on dynamic leakage rate are further investigated, providing a critical theoretical foundation for optimizing the sealing performance of S-DGS.

Efficient ortho–para hydrogen conversion is essential to suppress spontaneous heat release and boil-off losses during cryogenic liquid hydrogen storage and pre-liquefaction processes. In this study, a novel catalyst-filled wavy plate-fin heat exchanger (CFHE) is proposed to simultaneously enhance heat transfer and ortho–para hydrogen conversion under cryogenic conditions. Compared with conventional straight-fin configurations, the wavy-fin structure introduces controlled flow perturbations and increased specific surface area, thereby intensifying transport processes. Three-dimensional computational fluid dynamics (CFD) simulations, using the SST k–ω turbulence model, coupled with an ortho–para hydrogen conversion kinetic model were performed to quantitatively investigate the effects of key geometric parameters and catalyst loading on hydrogen conversion, heat transfer, and pressure drop within a Reynolds number range of 941–1577 and a temperature range of 35–20 K. Within the same CFHE configuration, the para-hydrogen fraction remains nearly unchanged without catalyst but increases significantly with catalyst loading. However, the catalyst reduces the global average Colburn j-factor by about 25%. Despite higher friction losses, the outlet–inlet temperature difference decreases to about 0.866 times that of the non-catalyst case, indicating improved temperature uniformity. A comprehensive performance index e, integrating heat transfer enhancement, flow resistance, and conversion efficiency, was introduced and optimized using a genetic algorithm. The optimized CFHE achieves an outlet para-hydrogen fraction exceeding 95% of the thermodynamic equilibrium value while maintaining hydrogen entirely in the gaseous phase to avoid catalyst deactivation. Overall, the catalyst-packed wavy channel configuration demonstrates superior conversion efficiency, enhanced thermal uniformity, and improved overall performance compared with straight-fin structures, providing quantitative design guidance for high-performance heat exchangers in cryogenic hydrogen liquefaction systems.

Abstract Radiative heat loss from cement rotary-kiln shells at 200–400 °C is a promising source for waste-heat recovery, but shell rotation prevents direct thermoelectric attachment and makes narrow-gap radiation–convection coupling the key constraint. This work develops a rotation-inclusive CFD framework using steady RANS with the SST k–ω model and gray surface-to-surface radiation to evaluate a non-contact radiative collector. The predicted outlet temperature is validated by on-site infrared thermography using a UNI-T UTi165B+ imager with an emissivity setting of 0.9 and an accuracy of ±2%. Experimental points are reported with error bars and assessed using a ±4% parity band. For a single collector plate, a speed-dependent regime is identified. The area-averaged plate heat-flux density is about 1378 W m−2 at zero rotation, remains within 1324–1359 W m−2 for ω ≤ 0.15 rad s−1, and decreases to about 1234 W m−2 at 0.30 rad s−1 as throat velocity rises and forced convection intensifies. For circumferential multi-plate installation, the radiative fraction stays nearly constant at about 41–45% with less than 1% variation, indicating that circumferential non-uniformity is governed by changes in absolute radiative load. An annular integrated collector is proposed to suppress bypass flow and stabilize the gap field. At L = 10 mm, rotation sensitivity is reduced and the circumferential temperature spread is about 1 K except near apex regions. A transition near L ≈ 18 mm is indicated by crown-side cooling and an inlet–outlet effect reversal, which provides a criterion for gap selection.

This experimental study examines the thermo-hydraulic performance of a parabolic trough solar collector using water-based Fe₃O₄ nanofluids with twisted tape inserts under simulated solar flux. Fe₃O₄ nanofluids with volume fractions of ϕ = 0.01–0.06 were circulated through a copper absorber tube equipped with twisted tapes of twist ratios (H/D) = 2.8, 3.9, and 5.4 over a Reynolds number range of 3,000–25,000. Compared with plain water, nanofluids produced higher inlet–outlet temperature differences, increasing from about 7–8 K to approximately 34–37 K when combined with twisted tape inserts at lower Reynolds number. The Nusselt number increased markedly with Reynolds number and nanoparticle concentration, reaching approximately 2–7 times that of plain water for combined nanofluid–twisted tape configurations. The friction factor increased by about 2–3.0 times due to enhanced swirl flow and higher effective viscosity. Despite this hydraulic penalty, the Performance Evaluation Criterion remained greater than unity for all cases, with PEC values generally ranging from about 1.42 to 5.18, confirming an overall thermo-hydraulic advantage.

Lost Circulation (LC) is one of the most common and high-risk complex situations encountered during drilling operations, posing a serious threat to the safe extraction and economic viability of oil and gas resources. Traditional wellbore leakage detection methods based on human experience often suffer from delays and uncertainties, making it difficult to meet real-time warning requirements under complex geological conditions. This paper proposes an LC warning method that combines a physical model with a combination of neural networks (Crested Porcupine Optimizer (CPO)–Long Short-Term Memory (LSTM)–Random Forest (RF)). The physical model utilises changes in mud pit volume, inlet–outlet flow rate differences, and riser pressure to construct interpretable event labels, thereby enhancing the physical plausibility of prediction results. The deep learning component employs LSTM networks to extract temporal features and RF for non-linear discrimination and introduces the CPO algorithm for feature selection and hyperparameter optimisation, thereby enhancing the model’s stability and generalisation capability. Validation using actual field data from the western Bohai Bay oilfield demonstrates that the proposed method outperforms traditional models in accuracy, precision, recall, and F1-score. It also offers a significant improvement in early warning time, detecting potential leakage about 17 min before traditional methods. These results highlight the effectiveness of the approach in managing risks during drilling operations.

Computational analysis of flow-induced stresses in cerebral aneurysms during normal and exercise conditions

Abstract A funnel arrangement system is essential in modern naval ships to cool the hot exhaust gas and suppress its infrared (IR) signature. Laboratory experiments utilising various funnel designs, specifically converging-diverging funnels, have produced promising results regarding the IRS model. The experimental analysis varied the Reynolds number between 4020 and 16800. At the same time, the temperature ratio was adjusted from 1.1411 to 1.2974, yielding significant insights into the relationship between mass flow dynamics and thermal efficiency in IRS devices. The present study proposes a novel type of funnel arrangement system featuring a converging-diverging funnel configuration. The thermo-fluid analysis of the proposed system involves solving transport equations, including continuity, momentum, energy, and turbulence, using the finite volume solver in ANSYS FLUENT. The study aims to determine the effective geometrical parameters, such as the inlet radius, outlet radius, radial overlap, and funnel inclination angle, to optimise the system's performance. The impact of these pertinent parameters on the air entrainment and system exit temperature is elucidated here. The funnel walls are assumed diathermic for the present analysis. The results show that maximum mass entrainment and lowest outlet temperature are achieved at a radial overlap of 0.3 m. A funnel inclination angle of 4° shows a maximum mass entrainment.

This study presents an eccentric pipe separator (EPS) designed according to the shallow pool principle and Stokes’ law as a compact alternative to conventional gravitational tank separators for offshore platforms. To investigate the internal oil-water flow characteristics and separation performance of the EPS, both field experiments with crude oil on an offshore platform and computational fluid dynamics (CFD) simulations were conducted, guided by dimensional analysis. Crude oil volume fractions were measured using a Coriolis mass flow meter and the fluorescence method. The CFD analysis employed an Eulerian multiphase model coupled with the renormalization group (RNG) k-ε turbulence model, validated against experimental data. Under the operating conditions examined, the separated water contained less than 50 mg/L of oil, while the separated crude oil achieved a purity of 98%, corresponding to a separation efficiency of 97%. The split ratios between the oil and upper outlets were found to strongly influence the phase distribution, velocity field, and pressure distribution within the EPS. Higher split ratios caused crude oil to accumulate in the upper core region and annulus. Maximum separation efficiency occurred when the combined split ratio of the upper and oil outlets matched the inlet oil volume fraction. Excessively high split ratios led to excessive water entrainment in the separated oil, whereas excessively low ratios resulted in excessive oil entrainment in the separated water. Crude oil density and inlet velocity exhibited an inverse relationship with separation efficiency; as these parameters increased, reduced droplet settling diminished optimal efficiency. In contrast, crude oil viscosity showed a positive correlation with the pressure drop between the inlet and oil outlet. Overall, the EPS demonstrates a viable, space-efficient alternative for oil-water separation in offshore oil production.