Belt Speed and RPM

[MolaKule]

I find that the linear velocity of my main drive belt (grooved drive belt) on my Frontier is 236 in/sec.

The main crankshaft (drive) pulley is 6" in Diameter.

What is the RPM of the engine under these conditions?

 

[SHOZ]

Measure the circumference of the pulley. That many inches is one rpm compared to the belt linear distance

 

[exranger06]

751.2 rpm.

 

[MolaKule]

Originally Posted By: SHOZ
Measure the circumference of the pulley. That many inches is one rpm compared to the belt linear distance

Ok, but can you show us your calculations on what the rpm should be?

 

[exranger06]

6 inch pulley times pi = 18.85 inches circumference.
236 in/sec divided by 18.85 inches = 12.52 revolutions per second
12.52 rps times 60 seconds = 751.2 rpm

 

[MolaKule]

Anyone else, Anyone Else?

https://www.youtube.com/watch?v=uhiCFdWeQfA

We'll wait for some more answers after the Supper crowd has been served.

 

[SHOZ]

Originally Posted By: MolaKule
Originally Posted By: SHOZ
Measure the circumference of the pulley. That many inches is one rpm compared to the belt linear distance

Ok, but can you show us your calculations on what the rpm should be?
I thought this was a class room thing and I just gave the start......

 

[Linctex]

I love these little "Practical" math problems you keep throwing out there!

 

[MolaKule]

This exercise was similar to

https://www.bobistheoilguy.com/forums/ub...ity#Post4707793

With Vt being given in this case, you had to work backwards to find the radians/sec and then convert to RPM.

In this case the RPM was ~ 720 RPM so my Frontier's engine was idling.


exrang06 provided a direct approach and correct answer so he receives the BITOG virtual Coffee Cup.