Gearbox Efficiency
Gearbox Efficiency
(OP)
Has anyone had any experience in testing, under controled conditions, gearboxes for overall efficiency and losses? I'm stepping into this particular testing area (I have been testing for almost 15 years now) for the first time and would like some theory behind the tests (I haven't been able to find much in my literature or the internet).
I know the premise for efficiency...the "goes-outta/goes-inta" but I'd like to get some insight into parameters measured and general idea behind quantifying losses.
Thanks.
I know the premise for efficiency...the "goes-outta/goes-inta" but I'd like to get some insight into parameters measured and general idea behind quantifying losses.
Thanks.





RE: Gearbox Efficiency
Author(s): Gangopadhyay, Arup, Asaro, Sam, Schroder, Michael, Jensen, Ron, Sorab, Jagadish,
Has some good details.
Cheers
Greg Locock
RE: Gearbox Efficiency
RE: Gearbox Efficiency
Thanks.
RE: Gearbox Efficiency
RE: Gearbox Efficiency
SAE paper 1999-01-0936
Cheers
Greg Locock
RE: Gearbox Efficiency
This is a brand new custom box we have designed for our test cell work. It is simply a speed multiplier (or reducer)since most of our work is done at very high speeds. The unfortunate part is that I have a round of testing coming up very soon that will require that we know what we are losing thru it. Unfortunately we have no data on this GB except theoreticals.
Thanks for the responses.
RE: Gearbox Efficiency
RE: Gearbox Efficiency
Thanks!
RE: Gearbox Efficiency
RE: Gearbox Efficiency
What about energy conservation: (steady state points over speed range of interest)
[Torque out x speed out] / [Torque in x speed in] x 100 = efficiency. [Torque in x speed in] - [Torque out x speed out] = heat, noise, etc. For 100 per cent efficient gear box the first equation = 100, the second = 0.
I am not sure why you need to compute the losses independent of the torque/speed functions, unless you need to troubleshoot problem areas, such as specific bearings and gear sets within the gear box.
RE: Gearbox Efficiency
My main concern is that this is a brand new design that has not had a chance to have been tested and I am going to have to throw it into the mix without any real knowledge on the box itself seperate from the actual test device it will be driving. I will have to look at 2 test articles instead of 1 which is not the way I prefer to run tests if I can help it. I definitely will be having the torque and speed measurements pre and post of the box like everyone has mentioned. My main concern was whether anyone who has done this sort of thing before worried about doing things such as a heat/energy balance to characterize their application or if they did it based solely on torque and speed.
In re. to what EM has said, I agree with you that there definitely will be aspects to the set up that I simply can not capture, i.e. convective and radiation sources. This GB will be right next to a gas turbine, so it's definitely not going to be an adiabatic situation. I will though be measuring temps in a lot of places to get a good thermal picture of what is happening in the GB.
Thanks for the input guys!