Search results
Results From The WOW.Com Content Network
Many plants use phytochrome to establish circadian cycles which influence the opening and closing of leaves associated with nyctastic movements. Anatomically, the movements are mediated by pulvini . Pulvinus cells are located at the base or apex of the petiole and the flux of water from the dorsal to ventral motor cells regulates leaf closure.
The valve timing of a diesel engine also depends on tappet clearance of the inlet and exhaust valves. If tappet clearance is less, then valve will open early and close late. [2] If tappet clearance is more, then valve will open late and close early. Tappet clearance is measured by an instrument called feeler gauge.
On the other hand, if the camshaft keeps the valves open for longer periods of time, as with a racing cam, problems start to occur at the lower engine speeds. Opening the intake valve while the exhaust valve is still open may cause unburnt fuel to exit the engine, leading to lower engine performance and increased emissions.
The exhaust port is connected directly to the cylinder wall. The transfer and exhaust port are opened and closed by the piston. The reed valve opens when the crankcase pressure is slightly below intake pressure, to let it be filled with a new charge; this happens when the piston is moving upwards.
A 4-2-1 exhaust system is a type of exhaust manifold for an engine with four cylinders per bank, such as an inline-four engine or a V8 engine. The layout of a 4-2-1 system is as follows: four pipes (primary) come off the cylinder head , and merge into two pipes (secondary), which in turn finally link up to form one collector pipe.
A stroke is the action of a piston travelling the full length of its cylinder.In a two-stroke engine, one of the two strokes combines primarily the intake stroke and the combustion stroke, while the other stroke primarily combines the compression stroke and the exhaust stroke, though technically since both ports are exposed during both the combustion and compression strokes, some reversion ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
In piston engines, the valves are grouped into 'inlet valves' which admit the entrance of fuel and air and 'outlet valves' which allow the exhaust gases to escape. Each valve opens once per cycle and the ones that are subject to extreme accelerations are held closed by springs that are typically opened by rods running on a camshaft rotating ...