In this research a performance of TurboExpander and Joule-
Thomson valve will be compared in a proposed system developed
in order to recover flare gas in oil fields outstations which not
connected to any gas plant and burns continually the entire
associated gases in the flare, and reuses the mentioned gases in
central process facilities as a fuel in gas turbines which use diesel
(as they have dual system gas-diesel), while the associated gases in
related outstations are burned.
An analytical study was done to explain the
relationship between the performance of gas accumulator, surge
tank and vacuum breaker valve and the profile of the pipe.
The study proved that effectiveness of protection means vary
according to the longitudinal path of pipe.
In this research, we described the behavior of the valve by a mathematical model of
the discharge pressure valve and then we studied the vibrations frequency of the hydraulic
system which has plotted the pressure in a short period of piston pump in
absence and in
presence of discharge pressure valve.
The results of this study showed special vibrations frequency relationship of the
discharge pressure valve and hydraulic system where this relationship could decide the
effectiveness of the protection system before loading. It also showed that dynamic pressure
factor in absence of discharge pressure valve is j1=110% while the presence of the valve
is j2 = 20%.
Servo pneumatic control systems are able to generate a big forces and high speeds with a high
accuracy. Thanks to proportional valves we are able to control the accuracy and speeds of
motions in servo pneumatic circuits.
Depending on the goal, alm
ost we use the linear cylinders. And we achieved a simulation of
servo pneumatic system using a single and double solenoid proportional valve for inducting
and control. And we confirmed here, that we can choose servo pneumatic components, sizes
and specifications by working on the model translated into linear, then checking the effects of
this model comparing with the complete nonlinear system.
This will help in choosing the components of servo pneumatic systems more easily and helping
the designer to achieve more complicated actual systems with more durability and less cost and
efforts to achieve the needed results.
Hydraulic drives are able to generate high forces and move large loads. With the help of proportional
valves, it is possible to control movements fast and accurately.
Depending on the application, a linear cylinder, a rotary cylinder or a rotary mo
tor are used. Linear
cylinders are most frequently used. The following designs are therefore confined to this type of drive. We
compare among various types of cylinders which are common by used. We compared different conditions
for cylinders with friction and without it.
تشكل الحاصات في الفروة من أصول مختلفة (رضـية – نـدبات الحـروق –
جراحية ....) تطبيقات رئيسية للعلاج بالتوسيع الجلدي.
منذ عام 1997 و عبر ثماني سنوات أُسستْ تجربة بالموسعات الجلدية ( في مشفى المواساة
الجامعي ) بأماكن مختلفة من الجسم لأكثر من 80 مريضا
ً، كان منهم 23 مريـضاً (31) %
في مستوى الفروة.
وصِفَتْ و شُرِحت في هذه التجربة تم التقنية الجراحية و مختلف أنـواع الـشرائح الجلديـة
المستعملة و تم وصف المواد المستعملة، كما شرحت المضاعفات و وضحتْ ذلـك بـصور
فوتوغرافية للحالات المرضية خلال مراحل العلاج المختلفة.
كما أجريت مقارنة النتائج لدينا مع نتائج دراسات عالمية مختلفة واسعة و حديثة.
