How to calculate engine power

To find the power of the engine of internal combustion) car, set it on a special stand, which will give its maximum power. If this is not possible, it is possible to calculate the power of the engineby measuring the dynamics of acceleration to 100 km/h after learning his ground in the Datasheet. Determination of the power of electroengine produce at his size, or measure the voltage and current in its windings, then perform a calculation.

You will need

• stopwatch, the tester, caliper.

Instruction

1. The power counting of the internal combustion engine automobilecar a rule, the maximum power of the engine of the vehicle indicated in the technical documentation, but with the development of the resource engine, its power decreases. To find her, driving the car on a special stand, where experts measure the power of the engine at the moment.
2. If this is not possible, find out from the registration certificate of the car's weight, calculate the weight filled him with fuel and driver, and then quickly accelerate the vehicle to 100 km/h, recording a time of acceleration in seconds.
3. For power counting the overall weight of the car, driver and fuel, multiply by 27.78 (this is the speed of 100 km/h converted to meters per second) squared, and divide by twice the value of acceleration P=27,782*m/(2*t). Get the power value in watts. In order to convert it to kilowatts, multiply by 1000. To translate a value in horsepower, power in kilowatts divide by 0,735.
4. Counting power electromotorconnect the motor to a source of electrical current with a known voltage. Tester, measure the amperage on each of its windings. Measurement spend in amperes. Find the sum of the currents in all the windings. The resulting value will be multiplied by the voltage of the source current: P=UI. This will be the consumed power electroengine.
5. To determine the power of the engine by its size, measure the diameter of the stator core and its length. The measurement produced in centimeters with a tape measure and a caliper. Determine the synchronous speed of the shaft and the network where is connected the engine.
6. Define constant pole division. Multiply the diameter at a synchronous frequency and the number 3.14 and divide the result by the product of the network frequency and the number 120 (3,14*D*n/(120*f)). At the polar division and number of poles determine the constant C for this engineusing the table. Calculate its power, multiplying constant, the square of the shaft diameter, the length of the casing, a synchronous speed and the number 10^(-6): P = C*D2*l*n*10^(-6). The calculation will be derived in kilowatts.