20 research outputs found
numerical study of steady flow inside a lid-driven square cavity for Reynolds number up to 50000
The flow inside a lid-driven square cavity have been imposed a wide controversy during these last decades.Multiple studies found to exist in the literature included this case, which is widely used for benchmarking in computational fluid dynamic due to the simplicity of geometry. some classes of studies have investigated the existence of steady flow in the driven cavity, they found a steady 2D numérical solution until 35000 value of Reynolds number.However, other classes of studies have stated that the flow in driven cavity submitted to a hydrodynamic instability and they illustrated a continuation méthode to locate the point at which a Hopf bifurcation occurs leading to a transition from a steady flow to unsteady.In the shade of these studies and with this uncertainty surrounding this subject we wanted to get more clarification especially for steady flow solutions.The present study represents a numerical computation for steady flow inside a lid-driven square cavity, the governing equation is solved using a finite volume method based on second order scheme of accuracy. Steady solutions are obtained for Reynolds numbers ascending from 100 to 50000, using a resolution of 1024 x1024 grid point. A good agreement with previous results in the literature, the work was done in this paper including proprieties of flow in the center of primary and secondary vortices, velocity components and numérical values for stream function and vorticity which assure a good example for benchmarking purposes
Intelligent Coordination of Traditional Power Plants and Inverters Air Conditioners Controlled With Feedback-Corrected MPC in LFC
Demand response programs have been receiving more serious attention as alternatives for participating in load frequency control. Inverter air conditioners (IAC) are acknowledged as suitable devices for demand response due to their increasing contribution to network consumption. Despite their potential, their use presents challenges, including delayed responses, variable interference, and the absence of coordination with traditional generation units, which may affect control performance. Also, existing control strategies fail to consider operational and physical constraints, resulting in possible model mismatches. In this paper, a model predictive control with feedback correction (MPCFC) is proposed to dispatch control signals to the IACs so they can effectively participate in the frequency control of an interconnected power system. The feedback correction method is presented to enhance prediction accuracy in the MPC and weaken the influence of model parameter mismatches and external disturbances. Furthermore, to minimize the impacts of communication delays on frequency overshoot/undershoot, this study introduces an intelligent supervisory coordinator based on an artificial neural network to coordinate the reaction of traditional generation units and IACs to correct significant frequency variations brought on by the time delays. The effectiveness of the developed control scheme is verified through numerical studies by comparing it with the IAC with PI and MPC controllers (without coordinator) and the system without IACs. Case studies are investigated on a two-area power system in MATLAB/Simulink environment, and the OPAL-RT real-time simulator is used to validate the results.</p
Dietary Crocin is Protective in Pancreatic Cancer while Reducing Radiation-Induced Hepatic Oxidative Damage
Pancreatic cancer is one of the fatal causes of global cancer-related deaths. Although surgery and chemotherapy are standard treatment options, post-treatment outcomes often end in a poor prognosis. In the present study, we investigated anti-pancreatic cancer and amelioration of radiation-induced oxidative damage by crocin. Crocin is a carotenoid isolated from the dietary herb saffron, a prospect for novel leads as an anti-cancer agent. Crocin significantly reduced cell viability of BXPC3 and Capan-2 by triggering caspase signaling via the downregulation of Bcl-2. It modulated the expression of cell cycle signaling proteins P53, P21, P27, CDK2, c-MYC, Cyt-c and P38. Concomitantly, crocin treatment-induced apoptosis by inducing the release of cytochrome c from mitochondria to cytosol. Microarray analysis of the expression signature of genes induced by crocin showed a substantial number of genes involved in cell signaling pathways and checkpoints (723) are significantly affected by crocin. In mice bearing pancreatic tumors, crocin significantly reduced tumor burden without a change in body weight. Additionally, it showed significant protection against radiation-induced hepatic oxidative damage, reduced the levels of hepatic toxicity and preserved liver morphology. These findings indicate that crocin has a potential role in the treatment, prevention and management of pancreatic cancer
Asymmetrical Flow Driving in Two-Sided Lid-Driven Square Cavity with Antiparallel Wall Motion
The two-dimensional flow in a two-sided lid-driven cavity is often handled numerically for the same imposed wall velocities (symmetrical driving) either for parallel or antiparallel wall motion. However, in this study, we present a finite volume method (FVM) based on the second scheme of accuracy to numerically explore the steady two-dimensional flow in a two-sided lid-driven square cavity for antiparallel wall motion with different imposed wall velocities (asymmetrical driving). The top and the bottom walls of the cavity slide in opposite directions simultaneously at different velocities related to various imposed velocity ratios, λ = -2, -6, and -10, while the two remaining vertical walls are stationary. The results show that varying the velocity ratio and consequently the Reynolds ratios have a significant effect on the flow structures and fluid properties inside the cavity
Insight into the Structural, Mechanical and Optoelectronic Properties of Ternary Cubic Barium-Based BaMCl<sub>3</sub> (M = Ag, Cu) Chloroperovskites Compounds
Prediction of new materials is crucial for the advancement of technology. Here, in this research work, the first-principle computation has been conducted utilizing the WIEN2K package to probe the structural, electronic, mechanical, and optical properties of barium-based chloroperovskites BaMCl3 (M = Ag, Cu) compounds. The optimized lattice constants are calculated for both compounds which are 9.90 Bohr for BaAgCl3 and 9.38 Bohr for BaCuCl3. To obtain better and more precise results for the electronic band’s structure, TDOS and PDOS (total and partial density of states), and the TB-mBJ potential approximation are employed. The indirect band gap (R–Γ) is found for both compounds having values of 1.173 eV and 2.30 eV for BaCuCl3 and BaAgCl3, respectively, which depicts its semiconducting nature. The calculation of elastic properties is conducted with IRelast code. The Cauchy pressure, Bulk modulus, Young’s modulus, Shear modulus, anisotropic ratio, Kleinman parameters, and Poisson’s ratio are calculated from the obtained elastic constants. The computation of elastic parameters indicates that the interested chloroperovskites are anisotropic, mechanically stable, hard to scratch, and ductile. From 0 eV to 40 eV incident photon energy ranges, the various optical parameter such as refractive index, absorption coefficient, dielectric function, reflectivity, extinction coefficient, and optical conductivity are analyzed. These compounds absorb maximum light within 5 to 25 eV incident photon energy. Hence, these materials are good light absorbers, therefore, they can be used in optoelectronic devices for high-frequency applications
Clinical features, socioeconomic status, management, short and long-term outcomes of patients with acute myocardial infarction: Phase I results of PEACE MENA registry.
BackgroundThe Program for the Evaluation and Management of Cardiac Events in the Middle East and North Africa (PEACE MENA) is a prospective registry program in Arabian countries that involves in patients with acute myocardial infarction (AMI) or acute heart failure (AHF).MethodsThis prospective, multi-center, multi-country study is the first report of the baseline characteristics and outcomes of inpatients with AMI who were enrolled during the first 14-month recruitment phase. We report the clinical characteristics, socioeconomic, educational levels, and management, in-hospital, one month and one-year outcomes.ResultsBetween April 2019 and June 2020, 1377 patients with AMI were enrolled (79.1% males) from 16 Arabian countries. The mean age (± SD) was 58 ± 12 years. Almost half of the population had a net income ConclusionIn the MENA region, patients with AMI present at a young age and have a high burden of cardiac risk factors. Most of the patients in the registry have a low income and low educational status. There is heterogeneity among key performance indicators of AMI management among various Arabian countries
Total ischemic time for STEMI.
BackgroundThe Program for the Evaluation and Management of Cardiac Events in the Middle East and North Africa (PEACE MENA) is a prospective registry program in Arabian countries that involves in patients with acute myocardial infarction (AMI) or acute heart failure (AHF).MethodsThis prospective, multi-center, multi-country study is the first report of the baseline characteristics and outcomes of inpatients with AMI who were enrolled during the first 14-month recruitment phase. We report the clinical characteristics, socioeconomic, educational levels, and management, in-hospital, one month and one-year outcomes.ResultsBetween April 2019 and June 2020, 1377 patients with AMI were enrolled (79.1% males) from 16 Arabian countries. The mean age (± SD) was 58 ± 12 years. Almost half of the population had a net income ConclusionIn the MENA region, patients with AMI present at a young age and have a high burden of cardiac risk factors. Most of the patients in the registry have a low income and low educational status. There is heterogeneity among key performance indicators of AMI management among various Arabian countries.</div
Questionnaire-typeset39MIO.
BackgroundThe Program for the Evaluation and Management of Cardiac Events in the Middle East and North Africa (PEACE MENA) is a prospective registry program in Arabian countries that involves in patients with acute myocardial infarction (AMI) or acute heart failure (AHF).MethodsThis prospective, multi-center, multi-country study is the first report of the baseline characteristics and outcomes of inpatients with AMI who were enrolled during the first 14-month recruitment phase. We report the clinical characteristics, socioeconomic, educational levels, and management, in-hospital, one month and one-year outcomes.ResultsBetween April 2019 and June 2020, 1377 patients with AMI were enrolled (79.1% males) from 16 Arabian countries. The mean age (± SD) was 58 ± 12 years. Almost half of the population had a net income ConclusionIn the MENA region, patients with AMI present at a young age and have a high burden of cardiac risk factors. Most of the patients in the registry have a low income and low educational status. There is heterogeneity among key performance indicators of AMI management among various Arabian countries.</div