A MATHEMATICAL MODEL FOR ESTIMATION OF GAS RESERVOIR PARAMETERS WITH USE OF OPTIMAL CONTROL THEORY
داود
خیرخواه
author
text
article
1989
per
Most of authors (17) have used discontinious methods based on
trial and error procedures for determination of optimum distribution
of kH and ?H. Optimal control theory has not been used for gas reservoirs.
Hence, in this paper optimal control theory is utilized for
mathematical simulation of gas reservoir and optimum distributions
of kH and ?H are presented. One of themain advantages of this new
model is generation of a continious system which does not require trial and error calculation.
University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26240_cc51c557fdbbba6763846a65727e8fde.pdf
INDUSTRIAL PRODUCTION, INPORTANCE AND USES
OF STYRENE MONOMER
دکتر ایرج
رضائیان
author
text
article
1989
per
The increasing use of styrene, for the production of thermOplastics and rubbers, has given a special importance to this vital materialin petrochemical industries. More than 95 per cent of styrene production in the world is by dehydrogenation of ethylbenzene. Present styrene production units are basically designed on the basis of 1940s units. Producing countries and related research centres have tried to use specific conditions and catalysts in order to get better conversion.
In this report, the importance, uses, technical problems in production methods
and the new pilot plant results are evaluated. In order to erect a new styrene
production unit with 200,000 tons capacity in a year, the calculated investment
required are about 24 million dollars in 1987.
Comparing this new method with similar present units there is 25 per cent
saving in steam and fuel requirements.
University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26241_8f60398e41e37da831d60e0450dffd8d.pdf
KINETICS STUDY OF DEC01PLEXATION OF SOME VANADIUM (V), MOLYBDENLM )VI) AND TOOSTEN(VI) AMINOCARBOXYLATE COMPLEXES.
دکتر کریم
زارع
author
text
article
1989
per
The kinetics of the de complexation by hydroxyl ions of some pervanadyl,
molybdate and tungstate amionocarboxyLate complexes have been studied spectrophotometrically
by means of a stopped flow technique. The chelate groups used were the
iminodiacetic acid (IDA), ethylenediarnineN,N' diacetic acid (EDDA), nitrilotriacetic
acid (NTA) and ethylene diamineN,N,N' ,N'tetraacetic acid (EDTA). The chelates
were 1:1 complexes except V(V)IDA which was 1:2. The rate law for decomplexation can be expressed by:
(q=2 for the V(V) chelates and q=l for the No(VI) and W(VI) chelates).
Kc is the stability constant of an outer sphere complex preequilibrium between
the chelate and hydroxyl ions, Ka is the rate constant of the direct decomplexation by water and Kb that by OH The slow step of the reaction should be an interchange between OH (or H20) and the chelate group in the outer sphere complex. The differences in the reactivities of the complexes are discussed. The most important effect observed on Ka and Kb is that, for a given metal, the rate constants diminish by a factor 100 to 1000 when a ligand which has vacant chelating sites replaces a ligand in which all the chelating sites are occupied. This is interpreted as an inductive effect by the acetate group, which is not bonded to the metal, on the nitrogenmetal bond.
University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26242_a63f0ae2e0edbbd99357f970cbd26fee.pdf
Use of Sponge Iron in Production of Cast Iron and Steel
خطیب الاسلام
صدرنژاد
author
جلیل وحدتی
خاکی
author
محمدرضا
ابوطالبی
author
text
article
1989
per
Laboratory and Industrial scale experiments are made on the application of
sponge iron pellets and briquettes for the production of cast iron and steel in
different melting systems, such as electric induction furnace, electric resistance furnace and fuelfired crucible furnace. Effect of various variables such as specifications of sponge iron, temperature of the molten metal and the method of feeding on the melting mechanism of the sponge iron, the melting time of the particles, the chemical composition of the molten metal and the weight of the slag are studied.
The results show that batch and continuous feeding operations whih up to 100 percent sponge iron materials are possible with an improvement in the quality of the products. These operations are, however, accompanied with a number of difficulties, such as, the production of an increasing volume of slag and the degradation of the refractories of the furnace. This is a result of the substitution of the iron ingots and the steel scraps, usually used as charge materials, with the sponge iron particles. These difficulties are especially severe when batch feeding operations are employed and if not resolved may cause a decrease in the efficiency of the operation and possible damage to the lining of the furnace.
University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26243_0d5f962096ba0e7adba2f1f655de5683.pdf

خطیب الاسلام
صدرنژاد
author
سید فرشید کاشانی
بزرگ
author
سعید حشمتی
منش
author
text
article
1989
per
Production of V and VNb Microalloyed Steels by Plunging Technique and Investigation of their Properties
University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26244_cf85ef26eebc66891481b85eb54b9464.pdf
Chaos and Energy:
Do the Fluctuations in the Petroleum Markets Have NonEconomic Causes?
جواد
صابر
author
کارولوکس
author
text
article
1989
per
In purpose of this paper is to discuss the occurance of bifurcation and
chaos in nonlinear systems in general, and the PearlReed model whi.ch has been used for representing the lynamical behavior of the petroleum resources in Particular. Based on this investigation, it is shown that the observed tluctuations in the petroleum market can be erplained by its interral dynamics and the increase in the growth rate of energy consumption will result in amplification of these fluctuations and ultimately, complete chaos in the energy market.
University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26245_6668334dba306effba907ee0e93df103.pdf
MATHEMATICAL MODELLING OF MULTI WINDING TRANSIOFMER
AND ITS EQUIVALENT CIRCUIT
حسین
محسنی
author
text
article
1989
per
A mathematical modelling for morewinding singlephase transformer is presented. The incidence matrixwhich gives the informations about the connection of the ends of the windings between the nodesis multiplied leftside and rightside with the inverse of the inductance matrix of the more winding transformer. The result is a matrix which gives the relationship between nodes potentials and nodes currents.
It is further shown that the obtained matrix represents an electrical network
including inductances without matual coupling.
A method for calculation of the inverse of the inductance matrix from the one
winding short circuited ind1,lctance matrix is developed. The reluctance of the core is considered to be constant. Some exampels are calculated.
University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26246_309f6071f0e0fe0034f204b2c6127eca.pdf
OVERVOLTAGE CAUSED BY WINDING TERMINAL ARRANGEMENT
OF THREE PHASE TRANSFORMER
حسین
محسنی
author
فرامرز
رهبر
author
text
article
1989
per
Usually both ends of a transformer winding are at the same side
of the magnetic core. With this arrangement there are automaticaly
the same number of the turns for each winding in both core windows
next to the middle leg of a three phase three leg core type transformer.
Contrary to this arrangement it is possible to put the two ends
of a winding at the different sides of the core. In this case the
same number of turns in 'the both core windows corresponding to the
windings on the middle leg does not exist. It means the amperturn of
the windings of the middle leg can not compensate each other in both
windows. If then the windings on the side legs be left free i.e. not
connected to a load or to a source, a strong magnetic flux flows
through both side legs, whichare in opposite direction to each others,
and an overvoltage would be induced in the windings on the side legs.
This can takplace during a shortcircuit, or through inrush current
or load.
In the paper above problem is discussed. The overvoltages caused
by this phenomena through a sudden one phase short circuit of a three
phase power transformer and the oscillation of the overvoltage caused
by saturation of the core are calculated and compared with the measurement.
University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26247_5acd352e7e9d09d08dc3a8f7d096a575.pdf
Improved genralized method for simulation of deepbars of cage rotors
مهندس ثابت
مزروقی
author
text
article
1989
per
The presented generalized method for sectionalizing the deepbar combines two new ideas, namely grading the heights of the bar sections, and grading the areas of the sections. In the particular case of the rectangular bar shape, the generalized method reduce itself to the method of grading of heights.
Throughout this paper four sections for the bar have been considered the
optimum number, so as to necessitate the availability of only small size and
cheap analog computers. Never the less the generalized method has proved successful with different bar stapes, even with this limitation on the number of sections into which the deepbar is divided. Naturally, this met rod is expected to lead to closer accuracy if ever required, with larger number' of sections.
University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26248_35cace2e06751618178a026fe78fd619.pdf
"The Limitation of the OneDimentional Fluid Flow Method for
Calculation of the Manometric Head of the Centrifugal Pumps"
دکتر احمد نور
بخش
author
text
article
1989
per
The nonuniformity factor is used for correction of the formulas obtained
from the onedimentional fluid flow method in a centrifugal impeller pump.
The variations of radial velocity at the outlet of five centrifugal impellers
with the specific speed of about Ns =50 are calculated at design point by using twodimentional potentional flow method for an invisid fluid.
On the other hand~ the variations of radial velocity across the outlet
width of the five impellers are measured at the design point by using triangular
probes.
The conclusion of these experiments and studies show that at design point
one can calculate~ with very good approximation~ the manometric head of an impeller by using the onedimentional fluid flow method and the nonuniformity factor.
We also found that the distribution of the radial speed across the width of
the impeller outlet is quite different from what was previously hypothesized by
some authors and pump desginers.
To further this study we suggest to determine the nonuniformity factor for
the flow rates other than the design point and also for the pumps with different
specific speeds.
University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26249_f20f90fed5f71a521cc6abf83721cf2c.pdf
Evaluation and Presention of a Method for :
THE DESIGN OF AN IMPELLER WITH TWODIMENTIONAL BLADES FOR
CENTRIFUGAL PUMPS
دکتر احمد
نوربخش
author
text
article
1989
per
University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26250_ab03858403d91c306f3f7a8ae504473d.pdf

دکتراردشیر
جهانشاهی
author
text
article
1989
per

University College of Engineering
دانشکده فنی
08031026
49
v.
0
no.
1989
https://jfe.ut.ac.ir/article_26251_8839c0e4cddd0bb0228ef8461c13b347.pdf