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Register a new userExperimental Study for Determination the temperature distribution of the roughness surfaces under natural convection
دراسة تجريبية لتحديد التوزيع الحراري لسطح مخشن صناعياً بالحمل الطبيعي
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Aِl-Baath University ورقة بحثية
Publication date
2016
fields
Mechanical Power Engineering
and research's language is
العربية
Created by
Shamra Editor
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هذا البحث يهدف بشكل أساسي لتحديد التوزيع الحراري بالحمل الطبيعي تجريبياً من ثلاثة سطوح مخشّنه صناعياً بمقاطع تخشينية منتظمة مختلفة (مقطع مثلثي, مقطع شبه منحرف, مقطع نصف دائري), و مقارنة ذلك مع سطح أملس غير مخشّن و بمساحة كل سطح تبادل.
This study aims mainly to determine the temperature distribution heat transfer enhancement under natural convection experimental, from three surfaces with industrial roughness created by a special machine (roughness surfaces) with triangular, trapezoidal, spherical configuration compared to equivalent smooth surface. With cross-sectional area.
References used
Al-Essa, A.H.; AL-Hussien, F.M.S., 2004- The effect of orientation of square perforations on the heat transfer enhancement from a fin subjected to natural convection. Heat and mass transfer vol 40, p.509-515
Al-Essa, A. H., 2000- Enhancement of thermal performance of fins subjected to natural convection through body perforation. Ph.D. thesis, Department of Mechanical Engineering, University of Baghdad, Iraq and University of science and technology of Jordan
AL-Essa, A. H., 2006- One Dimensional Finite Element Solution of the Rectangular Fin with Rectangular Perforations. wseas transactions on heat and mass transfer ,Issue 10, Volume 1, p762-768
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This research presents an empirical relationship between modulus
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from localized materials and containing several perecentages of
natural pozzolan (0 ,10 ,15, 20)% , also for tow cem
ent quantity
(350 ,400 ) Kg/m3 and for tow ages(28 ,90 ) day .Then comparing
the experimentally obtained result with the mechanical properties
calculated using the recommend relationship from the various
design codes. A new empirical relationship between elastic
modulus, and compressive strength for concrete containing natural
pozzolan is proposed.
One popular heat transfer augmentation technique involves the use
of rough surfaces of different configurations. The rough surface
aims to promote surface turbulence that is intended mainly to
increase the heat transfer coefficient and surface are
a. It was
reported that non-flat surfaces have free convection coefficients
that arrive to 50% to 100% more than those of flat surfaces.
The goal of this study aims mainly to examine heat transfer
enhancement from a surface with same industrial roughness created
by a special tool (roughness surfaces) with different shapes under
convection heat transfer compared to equivalent smooth surfaces
without deformations.
The results show there is no need to apply the different roughness
configurations in two mutually perpendicular directions. It's enough
to cause it only in one plane. And we have got the same win in
surface area.
The results show also the rectangular profiles of roughness give the
best result.
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very important in crowded cities), and it is also CO2-neutral in regards to
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amount of air for combustion, so the stoichiometric ratio for gasoline is
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The burning velocity and flame structure of ethanol –air mixtures over a
wide range of pressure and temperature have been studied using both a
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thermodynamic model was used to calculate the burning velocity from the
measured dynamic pressure rise in the spherical chamber. Photographic
observations were made through the end windows in the cylindrical
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In this research study the effect of adding thermal cement as a filler on the properties
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different ratios of thermal cement (0,5,10,15,20 pphr) on the rolling ru
bber machine, then
characterization physico-mechanical properties and chemical of mixtures that prepared
and then tested to measure the tensile strength, resistance friction and determine the
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The results showed increased tensile strength with increased thermal cement ratio
until
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as noted the low percentage of elongation at break gradually with increasing the proportion
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the proportion of thermal cement in mixtures, also observed a decrease in friction
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Direct steam generation in parabolic trough collector (DSGPTC)
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advantages and many researches have be done in
this field. Due to that reason this paper studies the convection
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from absorber tube of a PTC to all phases of
water (liquid water, wet steam and dry steam) along the
whole distance of fixed length of a DSG-PTC generates a high
temperature superheated steam (561 °C). All heat transfer
operations in PTC has been modelled and then the
convection' components which are; fluid temperature, tube
wall-fluid temperatures difference and heat transfer
coefficient have been analyzed in details at different
operation conditions such as inlet fluid pressure, direct solar
beam and mass flow.
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