Modeling of viscous flows in two-dimensional turbomachinery cascade via viscous-inviscid interaction method

[Abstract]: A two-dimensional time-accurate time-marching viscous flow solver employing the viscous-inviscid interaction method suitable for turbomachinery applications is described. The inviscid main flow solver uses the second-order accurate cellvertex finite-volume spatial discretisation and fourth-order accurate Runge-Kutta temporal integration. The viscous effect due to boundary layer development on the blade surfaces and wakes are modelled using an independent one-dimensional boundary layer subroutine capable of modelling laminar, transition and fully turbulent flows. The solver has been applied to subsonic, transonic and supersonic flow in a cascade of nozzle blades. The results are compared with the experimental data and they showed very good agreemen

Ultrawide phononic band gap for combined in-plane and out-of-plane waves

We consider two-dimensional phononic crystals formed from silicon and voids, and present optimized unit cell designs for (1) out-of-plane, (2) in-plane and (3) combined out-of-plane and in-plane elastic wave propagation. To feasibly search through an excessively large design space (10e40 possible realizations) we develop a specialized genetic algorithm and utilize it in conjunction with the reduced Bloch mode expansion method for fast band structure calculations. Focusing on high symmetry plain-strain square lattices, we report unit cell designs exhibiting record values of normalized band-gap size for all three categories. For the combined polarizations case, we reveal a design with a normalized band-gap size exceeding 60%.Comment: 4 pages, 1 figure, submitted for journal publicatio

Throughput, Spectral, and Energy Efficiency of 5G Massive MIMO Applications Using Different Linear Precoding Schemes

— A promising massive multiple input multiple output (M-MIMO) system is required to meet the growing need for highly traffic data, highly-resolution of streaming video, and intelligent communication on the fifth-generation wireless networks (5G). M-MIMO systems are essential for the optimization of the trade between energy efficiency (EE), throughput (R), and spectral _efficiency (SE) in wireless 5G networks. M-MIMO system architecture is proposed in this paper to enhance the trade-off between energy efficiency and uplink and downlink throughput at the optimum EE. Furthermore, using linear precoding techniques such as M MMSE, RZF, ZF, and MR, the EE-SE trade-off is optimized for uplink and downlink (M-MIMO) systems. The analysis of simulation results proved that throughput (R) is enhanced by increasing the number of antennas at optimum EE. After that, the proposed trading scheme is optimized and improved using M_MMSE compared to RZF, ZF. Finally, the results prove that M_MMSE gives the optimum trade-off between EE and R at the proved optimum ratio between the number of active antennas and the number of active users UE

Adsorption Study of Rhodamine –B Dye on Plant (Citrus Leaves)

تتضمن الدراسة الحالية امتزاز صبغة الرودامين B على سطح اوراق النارنج باستخدام تقنية مقياس الأشعة الفوق البنفسجية حيث تم تحديد البيانات الكمية للامتزاز (زمن التلامس، القوة الأيونية، درجة الحموضة، ودرجة الحرارة). تمت دراسة تأثير درجة الحرارة على عملية الامتزاز عند النطاق (25، 35، 45، و55) درجة مئوية حيث أظهرت النتائج بأن عملية امتزاز الرودامين B على مسحوق اوراق النارنج تزداد بزيادة درجة الحرارة مما يدل على أن عملية الأمتزاز عملية ماصة للحرارة. وبأستخدام تراكيز مختلفة من محلول كلوريد الصوديوم تم دراسة تأثير القوة الأيونية على عملية الأمتزاز.فقد ثبت أن زيادة القوة الأيونية تعمل على تحسين كمية أمتزاز رودامين B على أوراق النارنج عند درجات حرارة ثابتة. وأعطت النتائج أن كمية أمتزاز صبغة الرودامين B تزداد بزيادة PH للمحلول في المدى (3-7). ثم خضعت نتائج دراسة الامتزاز لنماذج متساوي الحرارة    Freundlich  , Langmuir و Temkin ، حيث تم تحديد معاملات كلا من Langmuir و  Freundlich و Temkin ، ووجد أن متساوي الامتزازيخضع  إلى متساوي الحرارة . Temkin  ,Freundlich تمت أيضًا دراسة المعاملات  الديناميكية الحرارية (مقدار التغيير في المحتوى الحراري ، ومقدار التغيير في الانتروبيا ومقدار التغيير في الطاقة الحرة لـ Gibbs) ووجد أن النتائج الديناميكية الحرارية لعملية امتزاز صبغة Rhodamine-B على مسحوق أوراق النارنج ماصة للحرارة وعملية الأمتزازعملية تلقائية.The current research includes the adsorption of Rhodmine-B Dye on the surface of Citrus Leaves using the technique of UV. Vis spectrophotometer to determine data of quantitative adsorption at various contact time, ionic strength, PH and temperature conditions. As a function of temperatures 25,35,45,55 0C, the dsorption phenomenon was examined, and the results showed that Rhodamine-B adsorption Citrus leaves rose with increasing temperatures on the surface (endothermic process). Using various NaCl solution concentrations, the effect of ionic strength on adsorption has also been studied. Increasing the importance of ionic strength has been shown to improve the amount of adsorption of Rhodamine-B on citrus leaves at constant temperatures.The quantity of Rh-B dye that was adsorbed on the citrus leaves was increased with increasing the PH of the solution in rang 3-7. Then the results were subjected to the practical results obtained with the use isotherms of the Langmuir, Frendelsh, and Temkin. The results can be shown that the isotherm suitable for adsorption applies to Ferndelsh and Temkin. The thermodynamic functions (the amount of change in enthalpy, the amount of change in entropy and the amount of change in the free energy of Gibbs) were also studied, and it was found that the thermodynamic results of the adsorption process of the Rhodamine-B dye on the powder of citrus leaves are endothermic and an automatic adsorption process

Optimization of vapex over consumption in one of the heavy oil cleft store

The process of solvent vapor extraction is a recycling method for the heavy oil application that the light hydrocarbon vapor is used as a solvent to reduce the heavy oil viscosity. The primary low recycling and the lower production flow compared with the thermal methods have faced the field applications with limitation due to the slow identity of the solvent penetration procedure in the heavy oil,. So in order to optimize and increase the production in this process, a simulation study was performed on one of the heavy oil cleft store of Iran and the solutions were presented to increase the oil recycling in this process. At first after construction of a cleft two dimensional store with multiple blocks that show the solvent vapor flowing in the cleft net, the optimization process was analyzed around two axes. First the optimization strategies presented to optimize the constructed solvent system injection in the process. Then the formation and distance between producing wells and injection on the process performance and the best condition were evaluated and developed. The results showed that the solvent composition injection method  through the producing well in addition to produce the injecting well in first ten days of process with more pressure and the well formation model with subsidiary distance and the vertical determined distance, the most optimized producing performance was presented compared to other plans, this results increase the security about the field application in the VAPEX process at cleft storesKey terms: optimization, solvent vapor extraction, heavy oil, cleft stores, wells  formatio

Production Planning of LCDs: Optimal Linear Programming and Sensitivity Analysis?

Aim: This research takes into the production of Flat Panel Monitor of four sizes and will point more the products that contribute the main function of profit. Methodology: For the optimization of the profit of LCDs manufacturing company, the linear programming and sensitivity analysis methods were applied. The four constraints of the LCDs production planning are (1) acquire of line space for production, (2) the assembly of products, (3) Quality control and assurance Hours (4) and packaging of material. Results: In all three scenarios the total profit is optimum and increases from scenario 1 to scenario 3. The difference between the profit of scenario 1 and scenario 2 is 257625, and gap between scenario 2 and scenario 3 is 171750. Conclusion: the three scenarios for the production of the LCDs present the varying consequences of the maximum profit for the company. However, the third scenario is the most optimal solution for the maximization of the objective function. Keywords: Production Planning, Linear Programming, Sensitivity Analysis, Simplex Method, Operations Research, LCD Monitor

Inertial amplification of continuous structures: Large band gaps from small masses

Wave motion in a continuous elastic rod with a periodically attached inertial-amplification mechanism is investigated. The mechanism has properties similar to an "inerter" typically used in vehicle suspensions, however here it is constructed and utilized in a manner that alters the intrinsic properties of a continuous structure. The elastodynamic band structure of the hybrid rod-mechanism structure yields band gaps that are exceedingly wide and deep when compared to what can be obtained using standard local resonators, while still being low in frequency. With this concept, a large band gap may be realized with as much as twenty times less added mass compared to what is needed in a standard local resonator configuration. The emerging inertially enhanced continuous structure also exhibits unique qualitative features in its dispersion curves. These include the existence of a characteristic double-peak in the attenuation constant profile within gaps and the possibility of coalescence of two neighbouring gaps creating a large contiguous gap.Comment: Manuscript is under review for journal publicatio