Un­de­sired Ro­ta­tion­al Vi­bra­tions in Com­bus­tion Engines

Ro­ta­tion­al and tor­sion­al vi­bra­tions in the focus

Ro­ta­tion­al or tor­sion­al vi­bra­tions de­note vi­bra­tion states of a sys­tem around its ro­ta­tion­al de­gree of free­dom, i.e. lin­ear elas­tic vi­bra­tion states around its own body axis. Since a com­bus­tion en­gine rep­re­sents a com­plex struc­ture or multi-mass sys­tem con­sist­ing of sev­er­al hun­dred in­di­vid­u­al parts, the pre­ven­tion of ro­ta­tion­al vi­bra­tions is at­trib­uted an es­sen­tial role. This is be­cause vi­bra­tions have a neg­a­tive ef­fect on the op­er­at­ing be­hav­ior of the en­gine. In ad­di­tion to in­creased ef­fi­cien­cy, re­li­a­bil­i­ty and longevi­ty are key fac­tors in the de­vel­op­ment of en­gines and tes­ti­fy to their high qual­i­ty.

Long-Term Loads in Engines

Po­ten­tial dam­age due to tor­sion­al vi­bra­tions

As a re­sult of the trans­la­to­ry move­ment of the pis­ton stroke, the crank­shaft is set in ro­ta­tion, which in turn in­tro­duces its ro­ta­tion­al en­er­gy into down­stream shafts. How­ev­er, the in­con­stant force trans­mis­sion of the acycli­cal lift­ing process pro­motes the oc­cur­rence of ro­ta­tion­al and tor­sion­al vi­bra­tions in the crank­shaft. The forced ro­ta­tion­al vi­bra­tions rep­re­sent a po­ten­tial source of dam­age if the ex­ci­ta­tion fre­quen­cy is close to the nat­u­ral fre­quen­cy of the shaft and thus pro­duces high am­pli­tudes. Over a longer pe­ri­od of time with many os­cil­lat­ing back­lash­es, ro­ta­tion­al vi­bra­tions pro­mote dam­age to shafts and down­stream com­po­nents such as gear­box­es.

High Pre­ci­sion Mea­sure­ment and Anal­y­sis Tech­nol­o­gy

Our so­lu­tion for ro­ta­tion­al vi­bra­tions in en­gines

A mea­sure­ment and anal­y­sis sys­tem that iden­ti­fies and an­a­lyzes dan­ger­ous ro­ta­tion­al vi­bra­tion con­di­tions. The IFTA sys­tems in con­junc­tion with the award-win­ning AT2 input mod­ule and the anal­y­sis soft­ware IFTA TrendView­er meet these chal­lenges. The cus­tom­iz­a­ble sys­tems en­able angle-re­lat­ed eval­u­a­tions of tor­sion­al vi­bra­tions in real-time. The re­sult­ing in­sights into the nat­u­ral fre­quen­cies of the tor­sion­al vi­bra­tions of the sys­tem pro­vide the basis for fur­ther im­prove­ments.

Rec­om­mend­ed Prod­ucts

Tor­sion­al Vi­bra­tion

Ap­pli­ca­tion so­lu­tion for tor­sion­al vi­bra­tion mea­sure­ment with timer AT2. 


Pro­tec­tion sys­tem with di­ag­nos­tic and mon­i­tor­ing func­tion­al­i­ty.


Di­ag­nos­tic tool for high-speed anal­y­sis & in­tel­li­gent vi­su­al­iza­tion.


Fast & in­­­tu­it­ive on­­line/of­f­­line ana­lys­is soft­­ware for ef­­fi­­cient vi­su­al­iz­a­­tion.