×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Vibration design for a Single linear engine

Vibration design for a Single linear engine

Vibration design for a Single linear engine

(OP)
hello,

we made a single linear engine(not a motorcycle engine), I just work for vibration design. but I find the Engine exciting force is too big and I don't know what kinds of monts can fits it.

anybody have the experience? Thanks!   

RE: Vibration design for a Single linear engine

Single cylinder engine?

Balancing the first-order vibration requires at least one balance shaft rotating at crankshaft speed but in the opposite direction, and preferably two such shafts spaced equally on either side of the crankshaft.

It can also be done the way the Ducati Supermono engine did it ... basically by making a "fake" second cylinder at 90 degrees (the Supermono used another connecting rod and a swinging mass) and arranging the inertia of that mechanism to match the piston and con-rod, and arranging the main counterweight on the crank to offset all of this.

A single cylinder engine without mechanical counterbalancing is always going to be rough.

RE: Vibration design for a Single linear engine

Couple other small things. How big and what kind of RPM are we talking about. A small high-revving single is a different ball game from a big low-revving single because of the time between power strokes.

Lightest possible pistons and rods will minimize the vibration.

RE: Vibration design for a Single linear engine

(OP)
thank you,BrianPetersen

yes ,it is a Single cylinder engine,15KW 1500Reciprocate per minute. our linear engine has not crankshaft, just a Reciprocating shaft.

Im sorry, my english is not very well, Im from china.
 

RE: Vibration design for a Single linear engine

What mass is the engine? What mass are the reciprocating components? What do you want your engine mounts to actually do?

 

Cheers

Greg Locock

SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.

RE: Vibration design for a Single linear engine

Is this homework? Are you a student?

Cheers

Greg Locock

SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.

RE: Vibration design for a Single linear engine

(OP)
GregLocock,
 
I work at a test department, it is not homework,
just a real engine. do you think the Amplitude and Acceleration are ok? thanks

RE: Vibration design for a Single linear engine

I cannot comment, because I can't read Chinese.

Also, what is "okay" depends on the application, which we know nothing about. If you are using this engine in a remote application with no people and no sensitive instruments anywhere in the area, then who cares how much vibration it makes. If you are using this engine to (say) reposition a telescope in an observatory, then even the tiniest vibration will make the image fuzzy. If you are using this engine in a luxury automobile, the amount of vibration that can be tolerated is very different from what can be tolerated in a fork-lift truck.

RE: Vibration design for a Single linear engine

(OP)
thanks!BrianPetersen,

 you are right. the engine is a prototype, we wanna use it at a series HEV as a power.

 does anybody have this experience?

RE: Vibration design for a Single linear engine

Are you measuring this with engine mounted solidly or are there rubber isolators between the motor and the base? Is the engine a 2 cycle or 4 cycle, gas or diesel fueled and how are you converting the piston movement to work?

Ed Danzer
www.danzcoinc.com
www.dehyds.com

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources