Low-temperature stratification, high-volumetric storage capacity, and less-complicated material processing make phase-changing materials (PCMs) very suitable candidates for solar energy storage applications. However, their poor heat diffusivities and suboptimal containment designs severely limit their decent storage capabilities. In these systems, the arrangement of tubes conveying the heat transport fluid (HTF) plays a crucial role in heat communication between the PCM and HTF during phase transition. This study investigates a helical coil tube-and-shell thermal storage system integrated with a novel central return tube to enhance heat transfer effectiveness. Three-dimensional computational fluid dynamics simulations compare the proposed design against a baseline helical coil system without a return tube under equivalent conditions. Outcomes quantify the return tube's efficacy in augmenting heat transfer uniformity and accelerating phase transition. Adding the return tube markedly boosts heat storage and recovery rates, increasing charging by 88% and discharging by 56% versus the baseline. Moreover, total phase transition time reduces by 48% for melting and 36% for solidification with the return tube. The accelerated charging stems from sustained convective heat transfer inside the return tube even as the molten layer thickens. Meanwhile, enhanced solidification results from ongoing cooling of inner regions. Isotherm analysis visualizes the return tube's efficacy in maintaining thermal uniformity throughout the phase transition process. Overall, the return tube significantly improves PCM thermal response, demonstrating a novel but straightforward approach to address heat transfer limitations in latent thermal storage systems.
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 su
... Show MoreThis paper studies the main characteristics of the traditional urban configuration of Arab cities, as an important built heritage, discussing the approach adopted with such configuration at the local level, and examines its ability to preserve the character of the city, as well as, its responsiveness to the recent requirements of its society that constantly change; in order to reach the appropriate procedures to deal with the traditional urban configuration of the Iraqi city to achieve a vital cultural communication with the vernacular built heritage, by dealing with the Form-Moral Values structure. Due to its importance within other traditional Iraqi cities, the research chose Al-Kadhimiya as a case study, so it discusses and compares
... Show MoreNumerical study of separation control on symmetrical airfoil, four digits (NACA
0012) by using rotating cylinder with double steps on its upper surface based on the computation of Reynolds-average Navier- Stokes equations was carried out to find the optimum configuration of unconventional airfoil for best aerodynamics performance. A model based on collocated Finite Volume Method was developed to solve the governing equations on a body-fitted coordinate system. A revised (k-w) model was proposed as a known turbulence model. This model was adapted to simulate the control effects of rotating cylinder. Numerical solutions were performed for flow around unconventional airfoil with cylinder to main stream velocities ratio in the range
... Show MoreThe aerodynamic characteristics of the forward swept wing aircraft have been studied theoretically and an experimentally investigation for the wake field generated by this configuration have been carried out. Low order panel method with the Dirichlet boundary condition have been used to solve the case of the steady, inviscid and compressible flow. Two different panel method techniques have been employed: the source-doublet and the doublet method. The thickness for the various components was considered in the study. Prandtl-Glauert similarity rule has been used to account for the compressibility effects. Experimentally, a model was manufactured from wood with body length (290mm) and main wing span was (204mm). The primary objective of th
... Show MoreThe transfer of chemical pollutants from bottled water into water due to heat, sunlight and poor storage is one of the most serious threats to human health around the world, the objective of this study was to estimate the pH value and the transport of heavy metals from plastic bottles to water, for this purpose, 30 bottles of water for 10 local brands were collected and divided into three groups, the first was left at room temperature 25°C, The second was placed in a heat oven at 25°C and the third in another oven at 50°C for two weeks. The results showed significant differences at (P<0.05) between water samples, pH value and concentrations of heavy metals (Sb, Pb, Ni, Cu, Cr, Cd and Fe) we
... Show MoreThe present work investigates the effect of magneto – hydrodynamic (MHD) laminar natural convection flow on a vertical cylinder in presence of heat generation and radiation. The governing equations which used are Continuity, Momentum and Energy equations. These equations are transformed to dimensionless equations using Vorticity-Stream Function method and the resulting nonlinear system
of partial differential equations are then solved numerically using finite difference approximation. A thermal boundary condition of a constant wall temperature is considered. A computer program (Fortran 90) was built to calculate the rate of heat transfer in terms of local Nusselt number, total mean Nusselt number, velocity distribution as well as te
This research provides a novel technique for using metal organic frameworks (HKUST-1) as a gas storage system for liquefied petroleum gas (LPG) in Iraqi vehicles to avoid the drawbacks of the currently employed method of LPG gas storage. A low-cost adsorbent called HKUST-1 was prepared and characterized in this research to investigate its ability for propane storage at different temperatures (25, 30, 35, and 40 oC) and pressures of (1-7) bar. HKUST-1 was made using a hydrothermal method and characterized using powder X-ray diffraction, BET surface area, scanning electron microscopic (SEM), and Fourier Transforms infrared spectroscopy (FTIR). The HKUST-1 was produced using a hydrothermal technique and possesses a high crys
... Show MoreABSTRACT
This research deals with the two item namely, the monetary policy central Bank of Iraqi and money supply . that contribute in up the problem of the paper that is concerned with the fact that to what extent the effectiveness of monetary policy conducted by the central Bank of Iraqi is valid in controlling money supply as well as the possibility of applying it in practical environment restricted to the scope of financial in stitiutions particularly in research population represented by central Bank of Iraqi .
For the purpose of a practical contribution for monetary and financial institutions . To achieve this , A hypothesis has been carried out and it suggested that the mon
... Show MoreThe research current ( features tendency cosmic in contemporary Iraqi configuration) attempt to study the dimensions of the conceptual and philosophical foundations upon which the tendency of cosmic within the period that extended its influence beyond the place where I grew up to be circulated concepts in all parts of the world, it is no doubt that the world is now heading to rapprochement after the tremendous developments in the field of communication technology and reflected heavily on identity concepts, privacy, the concept of nation-states ... etc. to become an individual and a large area of access to other cultures, and all that aroused the interest of contemporary Iraqi artist this interest arising from the desire to keep up with d
... Show MoreRepresenting banking supervision An important function performed by the Iraqi Central Bank, in order to achieve stability in the financial and banking system, and safeguard the rights of depositors, investors and other targets, and to realize the Iraqi Central Bank banking supervision actors on banks, there must be an awareness of regulatory bank's existing control and subject them, as well as the role of banking oversight interested in spreading this awareness.
So sought search to find out the role played by the Iraqi Central Bank in raising awareness of the regulatory banking between the parties to the regulatory process, through the presentation and analysis of the legal framework for banking supervision and awareness supervisory