Preferred Language
Articles
/
joe-707
Investigation of R134a Flow Boiling Heat Transfer and Pressure Drop in the Evaporator Test Section of Refrigeration System
...Show More Authors

This paper presents an experimental and theoretical analysis to investigate the two-phase flow boiling heat transfer coefficient and pressure drop of the refrigerant R-134a in the evaporator test section of the refrigeration system under different operating conditions. The test conditions considered are, for heat flux (13.7-36.6) kW/m2, mass flux (52-105) kg/m2.s, vapor quality (0.2-1) and saturation temperature (-15 to -3.7) ˚C. Experiments were carried out using a test rig for a 310W capacity refrigeration system, which is designed and constructed in the current work. Investigating of the experimental results has revealed that, the enhancement in local heat transfer coefficient for relatively higher heat flux 36.6 kW/m2 was about 38% compared to 13.7 kW/m2 at constant operating conditions. The enhancement in heat transfer coefficient was about 57% when the mass flux increased from 52 kg/m2.s to 105 kg/m2.s at constant test conditions. The enhancement in the heat transfer coefficient was about 64% when the saturation temperature increased from -8 to -3.7 at fixed refrigerant mass velocity and heat flux. The effect of mass velocity on pressure drop was relatively higher by about 27% than that for heat flux at specified test conditions. The comparison between the experimental and theoretical results has shown an acceptable agreement with an average deviation of 21%.

 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Mar 02 2014
Journal Name
Baghdad Science Journal
Comparison of Properties of Various Heat Storage Fluids used with Evacuated Tube of Solar Water Heater
...Show More Authors

The aim of this work was to capture solar radiation and convert it into solar thermal energy by using a storage material and the heat transfer fluid like oil and water and comparison between them, we used the evacuated tube as a receiver for solar radiation, The results showed that the oil better than water as storage material and the heat transfer fluid and the effective thermal conductivity material and good for power level, rates and durations of charge and discharge cycles.

View Publication Preview PDF
Crossref
Publication Date
Sun Dec 27 2020
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Phytochemical Investigation of the Aerial Part of Iraqi Convolvulus arvensis
...Show More Authors

 

Convolvulus arvensis is a species of bindweed that is rhizomatous and is in the morning glory family (Convolvulaceae) native to Europe and Asia. The plant is naturally grown in Iraq. The plant was reported to be used in traditional medicine from as early as 1730s.

The Aerial parts of Convolvulus arvensis were macerated in 80% ethanol for 6 days. The concentrated extract was partitioned with n-hexane, chloroform, ethyl acetate- and n-butanol successively. The n-hexane and ethyl acetate, fractions were examined for the presence of phytochemicals by thin l

... Show More
View Publication Preview PDF
Scopus (5)
Crossref (2)
Scopus Crossref
Publication Date
Wed Jan 01 2020
Journal Name
Jordan Journal Of Civil Engineering
Investigation of the impacts of nano-clay on the collapse potential and geotechnical properties of Gypseous soils
...Show More Authors

Preview PDF
Scopus (35)
Scopus
Publication Date
Fri Dec 01 2023
Journal Name
Baghdad Science Journal
Heat Production Rate and Radiation Hazard Indices from Radioactive Elements in Different Types of Natural Water in Nineveh Governorate, Iraq.
...Show More Authors

The current study sheds light on the measurement and estimation of the radioactivity of radionuclides (238U, 226Ra, 232Th, and 40k) in natural waters of different regions of Nineveh Governorate in Iraq.15 samples were collected from different sources of natural waters, where gamma-ray spectroscopy was used using NaI)TI) sodium iodide detector to determine the concentration of radioactivity in the samples. According to the results, the radioactivity concentration in the tested water sample were ​​ranged from 0.36 ± 0.04-1.57 ± 0.09with an average value of 0.69 ± 0.06 Bq/l for 238U, and 2.9 ± 0.02-0.88 ± 0.03 with an average value of 0.65 ± 0.03 Bq/l for 226Ra Bq/l

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Thu Jan 01 2026
Journal Name
Journal Of Studies And Researches Of Sport Education
Design and rationing test compound to assess the performance of the attack straight in terms of power characteristic speed And vital capacity for young players duel weapon Blinds
...Show More Authors

View Publication
Publication Date
Sat Dec 31 2022
Journal Name
Journal Of Life Science And Applied Research
THE ROLE OF OPTIFEED®, VÊO® PREMIUM, AND OLEOBIOTEC® IN DIETS FOR IMPROVEMENT OF THE PRODUCTION PERFORMANCE OF MALE BROILERS IN HEAT STRESS
...Show More Authors

The present study was conducted to investigate the effect of adding various levels of Optifeed®, VêO® premium and Oleobiotec® to the diets as appetite stimulants in the production Performance of broiler males under heat stress conditions. The experiment was done for 42 days for the period from 30 August 2018 to 11 of October 2018 at the Poultry Research Station of the Livestock Research Department / Agricultural Research Department / Ministry of Agriculture (Baghdad - Abu Ghraib). In this study, 270 - one-day broiler males (Ross 308) were reared with the mean body weight of 37 g/chick, distributed randomly on 18 pens with dimensions of 2 x 3 m (length x width). The experimental treatments involved six treatments with three repli

... Show More
View Publication
Crossref (13)
Crossref
Publication Date
Tue Mar 31 2015
Journal Name
Al-khwarizmi Engineering Journal
Experimental Study of the Thermal Diffusivity and Heat Capacity Concerning Some Duplex Stainless Steel
...Show More Authors

Abstract

In the present work, thermal diffusivity and heat capacity measurements have been investigated in temperature range between RT and 1473 K for different duplex stainless steel supplied by Outokumpu Stainless AB, Sweden. The purpose of this study is to get a reliable thermophysical data of these alloys and to study the effect of microstructure on the thermal diffusivity and heat capacity value. Results show the ferrite content in the duplex stainless steel increased with temperature at equilibrium state. On the other hand, ferrite content increased with increasing Cr/Ni ratio and there is no significant effect of ferrite content on the thermal diffusivity value at room temperature. Furthermore, the heat capacity of all sam

... Show More
View Publication Preview PDF
Publication Date
Fri Nov 08 2024
Journal Name
International Journal Of Language Testing
Validation of C-Test among Iraqi EFL University Students
...Show More Authors

.

View Publication Preview PDF
Scopus
Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
The Role of inherited occupations in cohesion of the family system
...Show More Authors

This study aims to study the inherited occupations which are considered to be a cultural, civilized and social legacy that effected by the Prevailing social and economic circumstances in the Iraqi society .
The study aimed to achieve several goals, including:
Identify the relationship between the urbanization and inherited occupations in the old city Al-Karkh.
Identify the relationship between the ecological construction and inherited occupations in the old city Al-Karkh.
Recognize the factors and motives inherited occupations in the study area .Identify the role of inherited occupations in promoting opportunities cohesion of the family system in the study area.
The field of the study had concentrated on a sample of famili

... Show More
View Publication Preview PDF
Publication Date
Tue Dec 16 2008
Journal Name
Journal Of Planner And Development
The system of urban stability in the Kurdistan Region of Iraq
...Show More Authors

The developing countries can be distinguished by spatial disparities and by this a wide gap between urban and rural settlements were produced as well as the appearance of primate cities. The effect of spatial development as a dynamic and continuous process can be perceived in the state of population distribution inside settlements inter and intra regions as well as the hierarchy of urban settlements according to time series. The research proved that the improvement judgment of the structure of the urban system using Gene factor is not accurate because it cannot be accounted for the internal components of the system which make a contrariety between the whole judgment (country) and partial components (Provinces including Sulaimaniy

... Show More
View Publication Preview PDF