The present work considers an alternative solution for a complex configuration of rotor discs by applying Galerkin Method. The theoretical model consists of elastic shaft carrying number of discs and supported on number of journal bearings. The equation of motion was discretized to finite degree of freedom in terms of the system generalized coordinates. The various effects of the dynamical forces and moments arising from the bearing, discs and shaft were included. Rayleigh beam model is used for analyzing the shaft while the discs are considered rigid . The validity and convergence of the present analysis was carefully checked by comparing with the Finite Element solution. An example of rotor consists of three different size discs and supported by two journal bearing was considered for the numerical solution .The results shows good agreements between the two methods ,where the maximum error not exceeds 5%. The convergence test showed that using few modes (not more than 6) are sufficient for the accurate analysis. The forward and backward whirl was investigated experimentally .The experimental results of a two discs rotor ,show a reasonable agreement where the maximum error not exceeds 11%. The unbalance response, Cambpell diagram, orbit response were plotted .The effects of geometry, disc sizes , location and arrangement on the unbalance response and natural frequencies of three discs rotor were further investigated .
The eff ect of partial substitution for lanthanum (La) on the structural properties of the compound Y1-xLaxBa4Cu7O15+δ were studied. The variation of (x) are x=0.1, 0.2 and 0.3, which was synthesized by solid state reaction method. The mixed powder was pressed with pressure (7 ton / cm2) as a disc (1.5 cm) diameter and a thickness of (0.25 to 0.3 cm). The samples were sintering by 120 °C / hour with a changing rate from room temperature to 850 ° C through 72 hours. XRD analysis using to calculate crystal size, strain and degree of crystallinity. It was found all samples have orthorhombic structure and change of structure with increasing lanthanum concentration. It was shown that the change lanthanum concentrations of all our samp
... Show MoreThe cartographic representation of geographical phenomenon considers the essential base in geographical analysis since as it supports the vertical house which is apartment houses consist of apartments which represent civil phenomenon , the aim of this study is to project the rule of cartographic representation methods in geographical analysis and make comparison in economic and social aspects for two approaches , the vertical and construction building methods.
The expand of city horizontally represent a problem in itself because it leads to loss of civil lands and overpass the agricultural lands as a result ,the ratio of habitation of land usage is so large in comparison with another usages of lands of the cities ; therefore ; many co
In this study, measuring effectiveness Alauriz in some seeds powder and found that the seeds of-sophistication sex had the highest effective enzymatic reach 353 units / gProtein and Alkabbatah study enzyme extract under different storage conditions and Altaj showed that the enzyme loses Thbatih and whether Mrkbhetwan adding Alklasrin concentration of 10% for the systematic solution
This research deals with the technical configuration of the beautiful visions among Bany Ahmar poets reflected through the incarnation of beautiful artistic images that manifests itself clearly in the combination of two contradictories simultaneously.
The main conclusion is, the Andalusian poets try to use those fictional visions in search of aesthetic pleasure and values, through forming an image from water and fire as two prominent contradicted elements to express the impact of the heat of wine which soon vanishes when it is mixed with water. By this, they show the beautiful side of nature that suggests joy and splendor.
For cleaner air and unpolluted continue assessment study air pollution the city of
Baghdad by measuring the concentrations of air pollutants, which included TSP, Pb, where
the adoption of three stations (Andalus Square, Jadiriya, Allawi) are distributed in the city of
Baghdad in order to compare the concentrations of these pollutants with previous studies.
Study pointed out that the city's air contaminant, especially in minutes outstanding after
deducting the amount of atmospheric dust thick mechanism city this year where the highest
concentration of minutes outstanding (9895) micrograms / m 3 at the station Alawi and lower
concentration of 157 micrograms / m 3 at the station Alawi and this was higher than the
det
This research aims to solve the nonlinear model formulated in a system of differential equations with an initial value problem (IVP) represented in COVID-19 mathematical epidemiology model as an application using new approach: Approximate Shrunken are proposed to solve such model under investigation, which combines classic numerical method and numerical simulation techniques in an effective statistical form which is shrunken estimation formula. Two numerical simulation methods are used firstly to solve this model: Mean Monte Carlo Runge-Kutta and Mean Latin Hypercube Runge-Kutta Methods. Then two approximate simulation methods are proposed to solve the current study. The results of the proposed approximate shrunken methods and the numerical
... Show MoreThe histological structure of integument in Mastacembelus mastacembelus have been investigated from skin fragments cut from nine regions at body surface. The results revealed that the integument of the fish investigated comprises three principal layers- the epidermis, the dermis (corium) and the subcutis-All the three principal layers may further be divided into secondary layers according to the function performed by their cells. The epidermis may further divided into three layers- the outermost epithelial coverage, the middle layer and the basal layer (stratum germinatiuum)-The dermis consists of a relatively thin upper layer of loose vascular connective tissue called the stratum laxum and a thick lower compact layer- the stratum compactu
... Show MoreIn this study, the adsorption of Zn (NO3)2 is carried out by using surfaces of malvaparviflora. The validity of the adsorption is evaluated by using atomic absorption Spectrophotometry through determination the amount of adsorbed Zn (NO3)2. Various parameters such as PH, adsorbent weight and contact time are studied in terms of their effect on the reaction progress. Furthermore, Lagergren’s equation is used to determine adsorption kinetics. It is observed that high removal of Zn (NO3)2 is obtained at PH=2. High removal of Zn (NO3)2 is at the time equivalent of 60 min and reaches equilibrium,where 0.25gm is the best weight of adsorbant . For kinetics the reaction onto malvaparviflora follows pseudo first order Lagergren’s equation.