Search results
Results from the WOW.Com Content Network
Brake horsepower (bhp) is the power measured using a brake type (load) dynamometer at a specified location, such as the crankshaft, output shaft of the transmission, rear axle or rear wheels. [ 30 ] In Europe, the DIN 70020 standard tests the engine fitted with all ancillaries and the exhaust system as used in the car.
Torque measurement is somewhat complicated since there are two machines in tandem - an inline torque transducer is the preferred method of torque measurement in this case. An eddy-current or waterbrake dynamometer, with electronic control combined with a variable frequency drive and AC induction motor, is a commonly used configuration of this type.
In physics and mechanics, torque is the rotational analogue of linear force. [1] It is also referred to as the moment of force (also abbreviated to moment). The symbol for torque is typically , the lowercase Greek letter tau. When being referred to as moment of force, it is commonly denoted by M.
Engine power is the power that an engine can develop. It can be expressed in power units, most commonly kilowatt, metric horsepower (often abbreviated PS), or horsepower.In terms of internal combustion engines, the engine power usually describes the rated power, which is a power output that the engine can maintain over a long period of time according to a certain testing method, for example ...
Speed has dropped out of the equation, and the only variables are the torque and displacement volume. Since the range of maximum brake mean effective pressures for good engine designs is well established, we now have a displacement-independent measure of the torque-producing capacity of an engine design – a specific torque of sorts.
The torque is then related to the lever length, shaft diameter and measured force. The device is generally used over a range of engine speeds to obtain power and torque curves for the engine, since there is a non-linear relationship between torque and engine speed for most engine types. Power output in SI units may be calculated as follows:
is the engine torque in newton metres (N⋅m) The above values of r, , and may be readily measured by instrumentation with an engine mounted in a test stand and a load applied to the running engine. The resulting units of BSFC are grams per joule (g/J)
Mercedes-Benz estimated that these changes, with vehicle modifications such as a stop-start system, give the 4.7–litre M278 22% lower fuel consumption and CO 2 emissions than the 5.5–litre M273 while producing more power 320 kW (435 PS; 429 bhp) versus 285 kW (387 PS; 382 bhp) and torque 700 N⋅m (516 lb⋅ft) versus 530 N⋅m (391 lb⋅ft).