This paper is targeting towards studying on the possibility to modify some properties
of unsaturated Polyester compounds by adding rubber materials in order to improve its
flexibility property. For this target, Waste of cars' tires was used in two
forms powder and
pieces, and the liquid rubber Styrene-butadiene was used as another type of rubber. After
that the modification was detected by measuring the possibility of the resulted compound
materials to absorb vibration power, and reduce the noise that is produced by eccentric
crankshaft circulation at different rotating speeds, (300, 500, 700) rpm.
Test results demonstrate that there will be Modification in the construction of the
compounds at low rotating speeds (300 rpm). On the other hand, it demonstrates different
results at high rotating speeds.
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%.
Worldwide wind turbines have steadily increased. They are very different in nature from conventional
generators.
Induction generators in large scale are used in wind turbines for their simple construction and reliable
operation.
With the increase
in penetration of wind turbines, the power system dominated by synchronous
machines will experience a change in dynamics and operational parameters.
This paper aims to analyze the impact of induction generators on transient and small signal stability of
power systems by gradually increasing the rate of power generated by wind turbines and changing the
location of these turbines in the power system.
The foundations are considered an important part for optimal operation and investment, and
for increasing productivty, and getting rid of all dynamic problems.
The research aims to show that when concrete foundations are preformed in an inconsisten
t
way, it will cause damaging vibrations in the machines. That was affirmed through a practical
case.
