xeddyhendrickst
26.05.2021 10:52:45
P.S. If a physicist or some other genius wants to chime in, feel free to. All comments are welcome here
See full version: Horsepower to pounds of thrust conversion
P.S. If a physicist or some other genius wants to chime in, feel free to. All comments are welcome here
Please help me, as it is giving me a headache here
Propeller slip is also something to be considered. Propeller slip takes the propeller's inherent inefficiencies into account and compares the result with a theoretically perfect propeller: [links]
I am wanting to know the difference between a Jet engine's thrust, and a Turboprop's Shaft Horsepower.
Hello all you greasy, skydrol covered mechanics
The answer relates to the fundamental way in which each of these engines works. Turbojet, turbofan, and rocket engines all work by directly accelerating a fluid to produce a thrust force, so it is most straightforward to rate these engines in terms of the size of that force. A piston engine, turboprop, or turboshaft is designed to perform mechanical work that turns a shaft. In other words, the engine creates a torque, and we saw earlier that one of the forms of the power equation relates power to the amount of torque created over time. The shaft that such an engine turns is connected to a propeller, which is an aerodynamic device that converts that power into thrust. The engine itself doesn't produce the thrust, but it turns a propeller that does. Also, two engines that generate the same power may not necessarily result in the same thrust since one may use a more efficient propeller than the other. For these reasons, it is more logical to rate these kinds of engines in terms of the power they create since that is the most direct quantity they produce.
Others may recognize the term distance over time as the definition of velocity (v), so we can also say that power is equivalent to the force it takes to move an object at a constant speed.
How a turboprop or turboshaft engine works
Luckily, we do have access to data from a NASA report that does provide all the data we need to illustrate a sample case. The data is provided for a Boeing 747-200 cruising at Mach 0.9 at 40,000 ft (12,190 m). In this example, the aircraft's engines produce 55,145 lb (245,295 N) of thrust, only a quarter of its rated static thrust, to cruise at a velocity of 871 ft/s (265 m/s). Using the equations provided above, we calculate the power generated by the 747 to be 87,325 hp (65,100 kW). [links]
It is these two forms of the power equation that are most applicable to aviation. For example, one of the common types of question we receive asks how to convert the pounds of thrust generated by the jet engine(s) on a particular plane into horsepower. The first factor we must consider is that the thrust figures provided for most planes are in "static" units. Consider for a moment the Boeing 747-200 with its Pratt & Whitney JT9D turbofans. These four engines generate a total static force rating of 219,000 lb (973 kN). However, this force is measured by placing the engine on a device called a test stand.
We can also think of this equation in two slightly different ways. Some readers may recognize that the force multiplied by distance represents another quantity called torque (T), so we can say power is equivalent to the torque a system generates over time.
To help you quickly find the result, here is a chart that compares pound of thrust to hp. [links]
45 x 24 x 0.85 x 0.9/746 = 1.11 hp here
And in theory, you can fondly get a rough idea of the horsepower of an electric motor by taking its rated current draw (amperes) and multiply it by the voltage. That is: more
So if you are calculating the thrust to power for speed/power and the ability to run all day, you should go straight with the regular outboard. Check out our comprehensive guide here: Trolling Motor vs Outboard.
The short answer is YES, but the lb thrust to horsepower conversion is a little tricky.
To convert thrust to horsepower, there are generally two methods more
If you are wondering what kind of force you can get from your engine, you will have to convert your horsepower to thrust. Thrust is the effect of pressure or force on an object. Horsepower is a measurement of power, which is the amount of work done over a specific amount of time. Converting horsepower to thrust involves the equation for power, which is the amount of force multiplied by the velocity, which is a measure of distance over time.
Divide the distance the object was moved in feet by the duration of the move in minutes to calculate the velocity. For example, if the object was moved 200 feet in 5 minutes, the velocity equals 200 divided by 5, which is 40. The velocity is 40 feet per minute.