Preferred Language
Articles
/
alkej-212
Energy Saving of Heat Gain by Using Buried Pipe Inside a Roof
...Show More Authors

Abstract

    This work deals with a numerical investigation to evaluate the utilization of a water pipe buried inside a roof to reduce the heat gain and minimize the transmission of heat energy inside the conditioning space in summer season.     The numerical results of this paper showed that the reduction in heat gain and energy saving could be occurred with specific values of parameters, like the number of pipes per square meter, the ratio of pipe diameter to the roof thickness, and the pipe inlet water temperature. Comparing with a normal roof (without pipes), the results indicated a significant reduction in energy heat gain which is about 37.8% when the number of pipes per meter of roof length is 3.0 , the ratio of pipe diameter to the wall thickness (D/W) is 0.20, and the water inlet temperature is 30°C, while the minimum ratio of reduction 24% is achieved when the number of pipes per meter, the ratio of pipe diameter to the wall thickness, and the water inlet temperature are 27, 30 and 33 °C, respectively. The results also showed that there is a very small effect of pipe centre position inside the wall on the final heat transmission.

Keyword: Water pipe, Roof heat gain, Solar-air temperature.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Sep 29 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Evaluation of transverse and tensile bond strength of repaired nylon denture base material by heat, cold and visible light cure acrylic resin
...Show More Authors

Background: Denture fracture is one of the most common problems encountered by the patients and prosthodontists. The objective of present study was to evaluate the transverse strength of nylon denture base resin repaired by using conventional heat polymerized, autopolymerized and visible light cure {VLC} resins, surface treatment that used for repair and adjustment of insufficient nylon denture bases and in case of addition of artificial teeth. As these corrective procedures are common chair side procedures in dental clinic. Materials and methods: One hundred twenty nylon specimens were prepared by using metal patterns with dimension of (65x10x2.5 mm) length, width, and thickness respectively for transverse strength test while for tensile b

... Show More
View Publication Preview PDF
Publication Date
Wed Dec 30 2009
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Mass Transfer Correlations for a Rotating Cylinder Electrode under lsothermal and Controlled Heat Transfer Condition
...Show More Authors

Mass transfer correlations for iron rotating cylinder electrode in chloride/sulphate solution, under isothermal and
controlled heat transfer conditions, were derived. Limiting current density values for the oxygen reduction reaction from
potentiostatic experiments at different bulk temperatures and various turbulent flow rates, under isothermal and heat
transfer conditions, were used for such derivation. The corelations were analogous to that obtained by Eisenberg et all
and other workers.

View Publication Preview PDF
Publication Date
Mon Oct 12 2020
Journal Name
Molecules
Phase Change Process in a Zigzag Plate Latent Heat Storage System during Melting and Solidification
...Show More Authors

Applying a well-performing heat exchanger is an efficient way to fortify the relatively low thermal response of phase-change materials (PCMs), which have broad application prospects in the fields of thermal management and energy storage. In this study, an improved PCM melting and solidification in corrugated (zigzag) plate heat exchanger are numerically examined compared with smooth (flat) plate heat exchanger in both horizontal and vertical positions. The effects of the channel width (0.5 W, W, and 2 W) and the airflow temperature (318 K, 323 K, and 328 K) are exclusively studied and reported. The results reveal the much better performance of the horizontal corrugated configuration compared with the smooth channel during both melti

... Show More
View Publication
Scopus (38)
Crossref (35)
Scopus Clarivate Crossref
Publication Date
Sat Mar 30 2013
Journal Name
Australian Journal Of Basic And Applied Sciences
CFD Simulation of Heat Transfer Augmentation in Constant Heat-Fluxed Tube fitted with Baffled Twisted Tape Inserts
...Show More Authors

Publication Date
Sun Mar 01 2015
Journal Name
Baghdad Science Journal
A study of adsorption isotherms for the removal of herbicide Atlantis WG from aqueous solutions by using Bentonite clay
...Show More Authors

The subject of this research involves studying adsorption to removal herbicide Atlantis WG from aqueous solutions by bentonite clay. The equilibrium concentration have been determined spectra photometry by using UV-Vis spectrophotometer. The experimental equilibrium sorption data were analyzed by two widely, Langmuir and Freundlish isotherm models. The Langmuir model gave a better fit than Freundlich model The adsorption amount of (Atlantis WG) increased when the temperature and pH decreased. The thermodynamic parameters like ?G, ?H, and ?S have been calculated from the effect of temperature on adsorption process, is exothermic. The kinetic of adsorption process was studied depending on Lagergren ,Morris ? Weber and Rauschenberg equati

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 01 2020
Journal Name
Baghdad Science Journal
Eyewitnesses’ Visual Recollection in Suspect Identification by using Facial Appearance Model
...Show More Authors

Facial recognition has been an active field of imaging science. With the recent progresses in computer vision development, it is extensively applied in various areas, especially in law enforcement and security. Human face is a viable biometric that could be effectively used in both identification and verification. Thus far, regardless of a facial model and relevant metrics employed, its main shortcoming is that it requires a facial image, against which comparison is made. Therefore, closed circuit televisions and a facial database are always needed in an operational system. For the last few decades, unfortunately, we have experienced an emergence of asymmetric warfare, where acts of terrorism are often committed in secluded area with no

... Show More
View Publication Preview PDF
Scopus (3)
Scopus Clarivate Crossref
Publication Date
Sun Jun 04 2017
Journal Name
Baghdad Science Journal
Studying the Electron Energy Distribution Function (EEDF) and Electron Transport Coefficients in SF6 – He Gas Mixtures by Solving the Boltzmann Equation
...Show More Authors

The Boltzmann equation has been solved using (EEDF) package for a pure sulfur hexafluoride (SF6) gas and its mixtures with buffer Helium (He) gas to study the electron energy distribution function EEDF and then the corresponding transport coefficients for various ratios of SF6 and the mixtures. The calculations are graphically represented and discussed for the sake of comparison between the various mixtures. It is found that the various SF6 – He content mixtures have a considerable effect on EEDF and the transport coefficients of the mixtures

View Publication Preview PDF
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Estimation of Bladder pressure by using poiseuilles equation
...Show More Authors

Equation Boizil used to Oatae approximate value of bladder pressure for 25 healthy people compared with Amqas the Alrotinahh ways used an indirect the catheter Bashaddam and found this method is cheap and harmless and easy

View Publication Preview PDF
Publication Date
Wed May 10 2023
Journal Name
Journal Of Engineering
Improving the Properties of Gypsum By Using Additives
...Show More Authors

Gypsum Plaster is an important building materials, and because of the availabilty of its raw materials. In this research the effect of various additives on the properties of plaster was studied , like Polyvinyl Acetate, Furfural, Fumed Silica at different rate of addition and two types of fibers, Carbon Fiber and Polypropylene Fiber to the plaster at a different volumetric rate. It was found that after analysis of the results the use of Furfural as an additive to plaster by 2.5% is the optimum ratio of addition to that it improved the flexural Strength by 3.18%.
When using Polyvinyl Acetate it was found that the ratio of the additive 2% is the optimum ratio of addition to the plaster, because it improved the value of the flexural stre

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Thu Jun 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
Analysis of Models (NAGARCH & APGARCH) by Using Simulations
...Show More Authors

Simulation experiments are a means of solving in many fields, and it is the process of designing a model of the real system in order to follow it and identify its behavior through certain models and formulas written according to a repeating software style with a number of iterations. The aim of this study is to build a model  that deals with the behavior suffering from the state of (heteroskedasticity) by studying the models (APGARCH & NAGARCH) using (Gaussian) and (Non-Gaussian) distributions for different sample sizes (500,1000,1500,2000) through the stage of time series analysis (identification , estimation, diagnostic checking and prediction). The data was generated using the estimations of the parameters resulting f

... Show More
View Publication Preview PDF
Crossref