Getting into space!
Rockets are the
foundation of modern spaceflight they
are 90% fuel and use mainly hydrogen and
oxygen to propel themselves, this is a
modern rocket engine it's called the
Bell Nozzel it's been used in all
rockets that have ever been made the
bell nozzle tries to focus as much of
the exhaust as possible into a straight
line this allows for the rocket to have
high efficiency efficiency being how
much of the exhaust can be focused into
as straight a line as possible higher
efficiency allows for higher thrust the
problem with the dahle nozzle engine is
that it cannot adjust itself as the
altitude of the rocket and the air
pressure around it changes the picture
on the left shows how a bell nozzle
engine works at low altitudes here the
air pressure is high and this causes the
exhaust to be compressed in certain
areas this reduces the efficiency and
also create shockwaves inside the
exhaust that can damage or even destroy
the engine at the best
possible altitude which is simply the
area where the pressure of the gases
leaving the engine is equal to the air
pressure around the rocket the exhaust
will form is almost straight line this
is where it has maximum efficiency at
high altitudes where there is low air
pressure the pressure of the gases
leaving the engine is higher than the
pressure of the air around it
this causes the exhaust to expand out
which reduces the efficiency by reducing
the thrust this is what a bell nozzle
engine attached onto a rocket looks like
at high altitudes
you can see the flame spreading out and
moving to the sides of the rocket
Rockets go through different stages at
the end of a stage a rocket will remove
part of itself by ejecting it this is
done for two reasons one when part of a
Rockets fuel tank is used up that part
is no longer useful
it's simply adding extra weight and is
not helping the rocket move removing it
removes that way while also keeping any
fuel that is all still left in the
rocket the other reason is their
different types of bell nozzle engines
work best at different altitudes for
example a small Bell nozzle engine will
work well at low altitudes because it's
not as good at focusing gases as a
result the exhaust will be compressed
well and the line will be as straight as
it can be at high altitudes however
since the small engines cannot focus the
exhaust well the exhaust will quickly
spread out a larger engine however is
better at focusing gases this would not
work well at low altitudes because the
we'll be compressed and would form into
an extremely into a much thinner line
that would be somewhat uneven and would
form shockwaves and high altitudes
however the ability of the large Bell
nozzle to compress or to focus gases
would be able to somewhat balance out
the effects of the low air pressure
around the rocket this is a potential
solution to the problems presented by
the bell nozzle engine this is called
the arrow spike engine it's been around
for decades now and is a highly
efficient type of rocket engine the
problem with the arrow spike engine is
that it simply has not received enough
money to be installed onto rockets yet
despite that it is still a very
promising engine here is a clip of the
arrow spike engine work being tested
this may not look very different from a
normal bell nozzle engine or at least
the exhaust may not look very different
since it is very close up however it
differs from the bell nozzle in some
fundamental ways whereas a bell nozzle
will often work against the air pressure
or at least the air pressure will work
against the bell nozzle the aerospike
engine uses the air pressure itself to
maintain high efficiency and low
altitudes as shown by the picture on the
left the high air pressure will squeeze
the thrust will squeeze the exhaust near
the body of the arrow spike however here
it is due to the shape of the arrow
spike and the way the exhaust leaves it
this compression is done without
creating an uneven shape and without
creating large shockwaves this allows
the rocket to keep high efficiency by
focusing everything into a thin and
mostly straight line at the best
possible altitude where the pressure of
the gases is equal to the air pressure
it will work the arrow spike will work
in a similar way to the bell nozzle the
exhaust will come out in a straight line
at high altitudes with low air pressure
there will be shockwaves that form from
recompression in the engine
however these shockwaves instead of
damaging the engine like with the bell
nozzle will actually prevent the exhaust
from spreading out in the aerospike
engine this allows the engine to
maintain a mostly straight shape and
will allow it to keep high efficiency in
major
revolution happening in the aerospace
industry right now is the reusable
rocket the reusable rocket is simply a
rocket that can be partially or
completely reused after being launched
it will do its job in space and will
come back and land back on the ground
this is important because until now
rocket launches or extra have been
extremely expensive because every new
rocket launch would require an entire
new rocket to be built with reusable
rockets however the same rocket can be
used many times again which would
greatly reduce the cost reusable rockets
are also very accurate in their landing
they can land on very small areas here a
rocket made by SpaceX is landing on a
pad in the ocean
at farmers we've seen a thing or two
especially lately you see you become
sweatband executive this shows SpaceX is
a private company the fact that a
private company has been able to create
this shows that larger government
programs can also accomplish this and
once reusable rockets become commonplace
the costs needed for space travel and
getting items into space will be greatly
reduced it will allow for more
operations to be carried out
there are many many different space
agencies run by many countries however
the most well known ones the largest and
most well known ones are run by the
United States of America the European
Union China Japan Russia and India in
recent times we have also seen private
companies like SpaceX and Blue Origin
joining in into informing space programs
and there are there are more space
agencies run by other countries but they
are not as large or well accomplished as
these this is a load of logo for NASA
the National Aeronautics and Space
Administration this is the logo for the
Chinese national space administration
this is the logo of the Indian Space
Research Organization this is the logo
of the European Space Agency this is the
logo of the Japanese exploration agency
this is the logo of Ross cosmos the
Russian space agency this is the logo of
SpaceX and this is look this is the logo
of Blue Origin another new private space
company that is the content of this
video this video has mostly been about
new advancements being made in space
travel in mainly in rocket engines what
is being used in rocket engines right
now and how two different types of
rocket engines will work I hope you
found this video useful
we'll be more likely soon
