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List of the contents of this article:

• 1, Is there a reasonable proportional range between the engine power of the car and the weight of the car?? _Baidu know...
• 2、How to calculate the ratio of fire truck
• 3. How to calculate the power ratio

Is there a reasonable proportional range between the engine power of the car and the weight of the car?? _Baidu knows...

1. When the car is more than 4t, the specific power is 35-11.If the calculated specific power is greater than this range, it is surplus, and if it is less than this, it is a small horse car.

2. There is a relative relationship, and there is no standard proportional relationship; a high-horsepower engine can drive a car with a heavy body normally according to the design requirements, otherwise it will be a small horse car -- a big car that can't be pulled, and then a big horse car -- a floating and unstable.

3. In theory, the lighter the car, the faster the acceleration. Physical principle, inertia is only related to quality. But it's not better to have a light specific gravity. The dynamics of a car depends on the body structure, wind resistance, tires and other factors. Of course, the most important thing is the power ratio.

4. The higher the value of power, the more powerful the engine, / the following number is the rotation speed, indicating the rotation speed when this power is reached. A smaller number is better. Torque indicates the size of the force. The greater the torque, the greater the strength./The last number is the rotational speed, indicating the rotational speed when this torque is reached. A smaller number is better.

5. The choice of engine power is often preliminarily determined by ensuring the expected maximum speed of the car.

How to calculate the specific power of the fire truck

Calculation formula: The specific power is equal to the maximum net power of the engine divided by the total mass of the car. Specific power is a comprehensive indicator to measure the power performance of a car, specifically refers to the ratio of the maximum power of the car engine to the total mass of the car. Generally speaking, for the same type of car, the greater the specific power, the better the power of the car.

Rative power: It is the specific energy of the battery per unit time. The size of the specific power characterizes the size of the working current that the battery can withstand. If the power is large, it can be discharged with a larger current.For example, when a silver-zinc battery is discharged at a medium current density, the specific power can reach more than 100W.kg-'; while when the zinc-manganese dry battery works at a small current density.

The horsepower conversion is almost 404kW, and the specific power is 20kW/t, which is already higher than the specific power standard required by the airport fire truck. The feeling of acceleration and pushing back must be very strong.

The long-nosed elephant JP25-meter-high jet fire truck adopts Man TGS34806×4 chassis, with a rated working height of 25 meters, a maximum working amplitude of 18 meters, a specific power of 11kw/T, and a maximum range of 80 meters of fire cannons.

The fire truck selected in the calculation is a heavy fire truck. The total weight of the whole vehicle is 300kN, the front axle weight is 60kN, and the rear axle weight is 2×120kN. There are 2 front wheels and 4 rear wheels, and the wheel pressure action size is 0.2m×0.6m. The selected floorboard is a one-way board with a span of 2m to 4m and a two-way board with a span of 3m to 6m.

Motor power ×15=shaft power, 315kw shaft power ≈362kw.

How to calculate the specific power

Calculation formula: The specific power is equal to the maximum net power of the engine divided by the total mass of the car. Specific power is a comprehensive indicator to measure the power performance of a car, specifically refers to the ratio of the maximum power of the car engine to the total mass of the car. Generally speaking, for the same type of car, the greater the specific power, the better the power of the car.

The calculation formula is: fan specific power = fan air volume/fan power. Among them, the air volume of the fan represents the gas flow through the fan per unit time, usually in cubic meters/hour or cubic feet/minute;The power of the fan indicates the power consumption of the fan, usually in watts or horsepower.

Calculation formula for specific power (kW/kg or kw/T): maximum net power of the engine/total mass of the car. Classification of automobile engines: According to the different power sources, automobile engines can be divided into diesel engines, gasoline engines, electric vehicle motors and hybrid engines, etc.

Ratio power = input ratio power/actual power. The gas-electric ratio of the air compressor unit (air pressure station) refers to the electricity consumed by the air compressor unit (air pressure station) every 1 cubic meter of compressed air (converted into an intake state) produced during operation, in KW*H/m3. That is, specific power = input specific power/actual power.

Rative power: It is the specific energy of the battery per unit time. The size of the specific power characterizes the size of the working current that the battery can withstand.If the power is large, it can be discharged with a larger current. For example, when a silver-zinc battery is discharged at a medium current density, the specific power can reach more than 100W.kg-'; while when the zinc-manganese dry battery works at a small current density.