اخواني سوف نبدا هنا باذن الله عرض مجموعه من المحركات التي تستخدم
في مجال الطيران و في غير مجال الطيران

كبدايه سوف نبدا في شرح المحرك المكبسي اولا و من ثم ننتقل الي المحرك النفاث

كان اول عرض لهذا المحرك عن طريق العالم Nikolaus Otto عام 1876 , لذلك عرف المحرك باسم Otto cycle , و هو يعتبر اكثر الانواع شيوعا في الوقت الحاضر و يستخدم
في السيارات و الشاحنات .

(الكرات الخضراء تمثل الشحنه الجديده من الوقود + الهواء .. و الكرات الرماديه تمثل العادم ... و الون البرتقالي يمثل شعله الاحتراق)

1- Intake في هذه المرحله يتحرك المكبس الي اسفل في حين دخول شحنه جديده
من الوقود + الهواء .

Intake.. During the intake stroke, the piston moves downward, drawing a fresh charge of vaporized fuel/air mixture. The illustrated engine features a 'poppet' intake valve which is drawn open by the vacuum produced by the intake stroke. Some early engines worked this way, however most modern engines incorporate an extra cam/lifter arrangement as seen on the exhaust valve. The exhaust valve is held shut by a spring (not illustrated here).

2- Compression يتم غلق الفتحتين المسؤلين عن دخول و خروج الهواء
مع الوقود بواسطه valves و يبدا المكبس في الصعود الي اعلي
لكي يضغط علي الهواء و يزيد من ضغطه داخل الاسطوانه

Compression... As the piston rises the poppet valve is forced shut by the increased cylinder pressure. Flywheel momentum drives the piston upward, compressing the fuel/air mixture.

3- Power بعد الانتهاء من المرحله السابقه و عندما يبدا المكبس في النزول
مره اخري فان شعله الاحتراق تنطلق spark plug لكي تشعل في الوقود مع
الهواء المضغوطين داخل الاسطوانه...و عند الاحتراق فان الوقود و الهواء معا
يضغطوا علي المكبس بقوه كبيره و تكون هذه هيا البارو التي ناخذها من المحرك

4- Exhaust عند نزول المكبس الي اخر مشواره في المرحله السابقه يبدا
الvalve المسؤل عن خروج الخليط المحترق من الهواء و الوقود
في الانفراج لكي يخرج العادم.

Exhaust.. At the bottom of the power stroke, the exhaust valve is opened by the cam/lifter mechanism. The upward stroke of the piston drives the exhausted fuel out of the cylinder.

# يتبع ان شاء الله #

ايها النــاظر بعدي في كتـــابـــــي ... مستفيـــدا منه مرغـــوب الطـــلاب

قــاطفــا منه ثمــارا نسقـــت ... بــاجتهـــادي بمشيبــــــي و الشبـــــــــاب

اهد لــي منـــك دعـــــا صالحـــــا ... و تحــــري فيه اوقـــــات الاجـــــــاب

Intake... The fuel/air mixture is first drawn into the crankcase by the vacuum created during the upward stroke of the piston. The illustrated engine features a poppet intake valve, however many engines use a rotary value incorporated into the crankshaft
في البدايه .. فان شحنه الهواء و الوقود .. يتم ادخالها عن طريق valve ..
و يتم ادخالها عندما يكون المكبس في اعلي مشواره (كما هو موضح في الرسم)

During the downward stroke the poppet valve is forced closed by the increased crankcase pressure. The fuel mixture is then compressed in the crankcase during the remainder of the stroke
اثناء هبوط المكبس .. فان قوه الضغط تذداد علي الvalve مما تودي الي اغلاقه
و في نفس الوقت يتم رفع الشحنه الي غرفه الاحتراق ليتم حرقها.

Compression

Compression... The piston then rises, driven by flywheel momentum, and compresses the fuel mixture. (At the same time, another intake stroke is happening beneath the piston
يبدا المكبس في كبس الهواء و الوقود لزياده ضغطهم ..
و في نفس الوقت يبدا عمليه دخول لشحنه هواء جديده (كما هو موضح بالرسم)

Power... At the top of the stroke the spark plug ignites the fuel mixture. The burning fuel expands, driving the piston downward, to complete the cycle
بعد الانتهاء من عمليه كبس الهواء مباشره .. تبدا شعله الاحتراق spark plug في حرق الهواء و الوقود بعد وصولهم الي ضغط كبيير لكي يسهل احتراقهم..
و يتولد عن هذا الاحتراق انه يدفع المكبس بقوه كبيييره جداا الي الاسفل و هذه القوه الكبييره هي قوه المحرك التي نستفيد منها

a two stroke engine is usually more powerful than a four stroke engine of equivalent size

Transfer & Exhaust

Transfer & Exhaust... Toward the end of the stroke, the piston exposes the intake port, allowing the compressed fuel/air mixture in the crankcase to escape around the piston into the main cylinder. This expels the exhaust gasses out the exhaust port, usually located on the opposite side of the cylinder. Unfortunately, some of the fresh fuel mixture is usually expelled as well
اثناء هبوط المكبس .. فانه يسمح بخروج الشنحه المحترقه و في نفس الوقت يسمح
بدخول الشحنه الجديده لكي يتم احتراقها داخل غفه الاحتراق (كما موضح بالرسم)

يستخدم هذا المحرك في ...
( متسكلات البحر - درجات بخاريه خفيفه - نماذج الطائرات - درجات ناريه خفيفه - ...)

* للاسف فان هذا المحرك اسوء بكثير من المحرك السابق
من حيث انه ملوث جدااا للبيئه بسبب هروب كميات كبيره
من الوقود الغير محترقه خارج اسطوانه الاحتراق.

# يتبع ان شاء الله #

هو محرك رائع و زكي جدا من حيث التصميم و يعتبر افضل من otto cycle
و تم بتطور العالم Felix Wankel في عام 1950

In the Wankel a triangular rotor incorporating a central ring gear is driven around a fixed pinion within an oblong chamber
الحركه الدورانيه تتولد من دورانه حول ترس كبييير متحرك ياخذ حركته من ترس اخر اصغر منه
في الحجم و ثابت لا يتحرك

The fuel/air mixture is drawn in the intake port during this phase of the rotation.

The mixture is compressed here.

The mixture burns here, driving the rotor around.

And the exhaust is expelled here.

The rotory motion is transferred to the drive shaft via an eccentric wheel (illustrated in blue) that rides in a matching bearing in the rotor. The drive shaft rotates once during every power stroke instead of twice as in the Otto cycle. ok
الحركه الدورانيه يتم نقلها الي العمود shaft via عن طريق حلقه دورانيه ليست في المركز
و الموضحه باللون الازرق.
The Wankel promised higher power output with fewer moving parts than the Otto cycle engine, however technical difficulties have apparently interfered with widespread adoption. In spite of valiant efforts by Mazda, the four stroke engine
remains much more popular

ايها النــاظر بعدي في كتـــابـــــي ... مستفيـــدا منه مرغـــوب الطـــلاب

قــاطفــا منه ثمــارا نسقـــت ... بــاجتهـــادي بمشيبــــــي و الشبـــــــــاب

اهد لــي منـــك دعـــــا صالحـــــا ... و تحــــري فيه اوقـــــات الاجـــــــاب

The Atkinson engine is essentially an Otto-cycle engine with a different means of linking the piston to the crankshaft. It was originally designed to compete with the Otto engine, but without infringing on
any of Otto's patents

هو يعتبر مثل محرك Otto-cycle engine و لكن بطريقه مختلفه لربط الpiston مع ال crankshaft ..
و هو صمم خصيصا لكي ينافس محرك Otto-cycle في التصميم و لكن مع مراعاه حقوق
محرك Otto-cycle في براءه اختراعه .

# يتبع ان شاء الله #

عند دخول الهواء المضغوط الي غرفه الاحتراق .. فانه يتم اشعاله بواسطه شعله للاحتراق فيتم بذلك
ارتفاع حرارته و ضغطته بصوره كبيره و من ثم عند خروجه من الغرفه فانه يولد قوه الدفع
التي يخرجها المحرك

بعد اكتمال احتراق الهواء و الوقود و عند خروجه فاننا نستخدمه لكي نشغل التربينه و هيا مجموعه من الريش
متصله مع بعضها البعض علي محور واحد .. و لكي نتاكد من ان الهواء سيقوم بلف التربينه فاننا نضع stator
بين كل مروحتين من مراوح التربينه .. و فائدته انه يحدث توجيه للهواء المحترق
بحيث يعمل دوران جيد للتربينه

و هو صوت القطارات التي نسمعها

This style steam engine employs the cylinder as the steam valve
It operates on the same principle as the locomotive steam engine
( الكرات الحمراء تمثل شحنه الهواء الجديده ..الكرات الخضراء و تمثل الهواء المحترق مع الوقود )

Steam from the boiler enters the power manifold and is and is admitted to the top end of the cylinder when the cylinder port aligns with the manifold port. The steam presses the piston downward, driving the flywheel around
one half turn

At the end of the stroke the cylinder shifts, exposing the top port to the
exhaust manifold. The expended steam is released

At the same time, the bottom cylinder port, aligns with the power manifold, admitting steam to the bottom end of the cylinder. This presses the piston
upward, driving the flywheel around another half turn

At the end of the stroke, the bottom port aligns with the exhaust manifold, releasing the expended steam

Due to its exceedingly simple construction, this type of engine is popular in working toy steam engines, including one I had as a kid. An even simpler type employs power in only one direction, relying on flywheel momentum to carry the piston around for the remainder of the cycle. This is called a single acting engine. The type illustrated here is a double acting engine

# يتبع ان شاء الله #

I first learned of this delightful engine while attending the PRIME show in Oregon. A most prolific modeler, Marlyn Hadley, had one on display. I referred to his excellent book6 to create this illustration
I have not illustrated the valve linkage, as I'm not exactly sure what it looks like! It appears to be a rotary type, incorporated into the main drive shaft. Steam would be admitted to one end of the cylinder at a time, just as in any other double-acting steam engine.
The inner dimension of the stationary ring is not circular, but is slightly elliptical. The main bearing is offset from the center of this ellipse by a one half the stroke length

# يتبع ان شاء الله #

At the top of the stroke, the pin on the cylinder presses the ball valve upward, admitting high pressure gas into the cylinder
عند ارتفاع المكبس الي اعلي مشواره فانه يضغط علي الكره الموضحه في الرسم .. مما يسمح
بمرور الغاز الي داخل غرفه الاحتراق

The gas expands, driving the piston downward

when the piston advances past the exhaust port, the high-pressure gas is released

Flywheel (or propeller) momentum carries the piston upward to complete the cycle

This animation also illustrates the CO2 reservoir, or "fuel tank." Compressed CO2 is a liquid and becomes a gas as the pressure is released... Another way to state this is that the liquid CO2 boils at normal atmospheric temperature and pressure, so one might say this engine runs on "CO2 steam

Model engines of this type have been made to incredibly small dimensions. Stefan Gasparin produces one with a displacement of only 3.2 cubic millimeters!

# يتبع ان شاء الله #

Crank Substitute Engine

Like the Coomber, this engine also came from Marlyn Hadley's wonderful book.6 I can do no better than to quote him



This elaborate arrangement of gears and linkages enabled the builder to eliminate the crank as we know it. While this engine required more labor to construct, it did make a compact engine which did not require a heavy crosshead as the connecting rod connection on the bar between the two gears moves but a very small amount. This means the piston rod guides can be made of a lighter construction

I do not know who invented it, when, or what prompted the inventor to think this arrangement is better than a crank...


# يتبع ان شاء الله #

Revolving Cylinder Engine



This is yet another of Marlyn Hadley's6 model engines. The inventor is not known

The valve is not illustrated, but is apparently a rotary type, admitting steam to one end of the cylinder at a time

# يتبع ان شاء الله #

Watt Beam Engine





This illustration shows the general arrangement of a typical beam engine. Beam engines were used in many factories to drive machinery of all types and were sometimes built to enormous proportions. I have omitted the valve gear, as it was substantially the same as the locomotive engine.

It was important to restrict the motion of the piston and rod to a straight line in order to reduce friction and wear on the upper cylinder seal. The Watt linkage illustrated here is one of many contrivances for accomplishing this linear motion.

# يتبع ان شاء الله #

ايها النــاظر بعدي في كتـــابـــــي ... مستفيـــدا منه مرغـــوب الطـــلاب

قــاطفــا منه ثمــارا نسقـــت ... بــاجتهـــادي بمشيبــــــي و الشبـــــــــاب

اهد لــي منـــك دعـــــا صالحـــــا ... و تحــــري فيه اوقـــــات الاجـــــــاب

Another Beam Engine




This illustration shows a beam engine with yet another linear motion linkage. I found this linkage in Five Hundred and Seven Mechanical Movements. The book did not say who invented this linkage or what it is called

اي شخص عنده معلومه عن هذا المحرك .. فليتفضل و يتكرم و يعطيها الينا
لاني لم اجد عنه اااي معلومات مفيده

# يتبع ان شاء الله #