The objective of utilizing a dynamometer would be to test the strain capacity for a train locomotive just before putting it back in service. It enables for that break-in of a new or newly rebuilt engine inside a controllable
environment. Engine manufacturers, rebuilders and many fleets have proven this kind of break-in procedure through years of experience. Properly run-in engines keep going longer, run better and price less to keep up. This article highlights the whole process of the water brake engine dynamometer.
An electric train engine with no load are only able to produce speed. Maintaining confirmed rate of revolutions per minute (RPM) requires a very small amount of engine horsepower. The dyno can be a means by that your controlled load could be added and monitored. Using a water brake dynamometer, the horsepower from the prime mover is changed into heat with the dynamometer water. The stators and rotors successfully accomplish that change in energy. Both stators and rotors have pockets built within them. As water is brought to the engine dyno or chassis dyno by passages in the stator, it's discharged to the dyno close to the center of rotation from the rotor assembly. This water entering the dyno will flow to the pockets with the rotor. Water will be accelerated by the rotation with the rotor assembly, which is attached to the output shaft from the engine. Because it speeds up (or accelerates), the lake tends to fly out due to centrifugal force. And as the water flies out, it results in pockets in the stator plates. The water in these similar pockets within the stator plates
has a tendency to go out and it is once more met from the rotating rotor assembly. The lake is sped up (or accelerated) again, and also the constant acceleration and deceleration of the water, power is necessary which is changed into frictional heating of the water. The thermal conversion of engine chance to frictional heating with the water is based on pure laws of physics.
Horsepower can be defined in terms of heat. Heat loads
are measured when it comes to "BTUs" or British Thermal Units. A BTU of heat is the amount of heat which it would take to enhance the temperature of one pound of pure water by one degree Fahrenheit. When confronted with water brake dynamometers, heat loads in terms of BTUs are essential.
Because we have been raising the temperature of just one pound of water by one degree Fahrenheit, we'll have to know other definitions. You can find 62.4 pounds of pure water inside a cubic foot. There are 231 cubic inches in a single gallon of pure water. Therefore, one gallon of pure water would weigh 8-⅓ pounds. One horsepower is equivalent to 2,545 BTUs hourly or about 45.5 BTUs per minute. With this information, we can now determine the amount of water that's necessary to absorb certain level of horsepower. The quantity of water in the dyno at a instant determines the amount of horsepower that it could absorb. The harder water that is within the dynamometer, the greater the dyno can absorb. You can't put more water into the dyno compared to the amount for the amount of horsepower which you intend to test.
The dynamometer does not hold water. It is simply an instrument for converting the horsepower into heat with the water. For this reason, you'll need a given flow through the dyno at a given horsepower rating. The amount of flow varies because there are many horsepower being absorbed and is directly proportional. The greater the quantity of load required, the greater the level of water must be supplied.
The amount of water supplied for the dynamometer is controlled externally to the dynamometer. This can be done either with a pair of manual shut off valves mounted in water supply line, by the electric remote load control valve or from the servo-operated inlet manifold option. Whether or not the manual or electric valves are employed, both accomplish the identical task. The broader the valve is opened, the greater water it allows to circulate for the dynamometer. This flow towards the dyno is directly proportional to the level of horsepower being absorbed.
An exhaust or outlet valve is also mounted on the dynamometer. The goal of this valve would be to conserve water while allowing the dynamometer to operate on various temperatures of inlet water. Even as are converting horsepower into alguno (pocketpussytoy.com
) heat of the water, the connection of the inlet and outlet water temperatures becomes an essential consideration. The exhaust valve is a controlled orifice. The farther it really is opened, the higher the water consumption will be.
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