%0 Generic %1 allnutt1980control %A ALLNUTT, J %A PRICE, S %A TUNSTALL, M %D 1980 %K Aerodynamics Bundle Conductor Damping Oscillation Spacer Sub-span %T THE CONTROL OF SUB-SPAN OSCILLATION OF MULTI-CONDUCTOR BUNDLED TRANSMISSION LINES %X The physics of sub-span oscillation is discussed in simple terms in order to elucidate the role of the various mechanical parameters. The results of a limit cycle analysis of a simple model show that mechanical damping has a relatively small effect on motio~ amplitude until high values of damping are reached. Tests on typical commercial twin spacer dampers, using a mechanically-excited, low level test line, show that suitably high values of damping are unlikely to be achieved. The effect of the ratios of certain bundle natural frequencies on the instability is shown to be of great importance ; the experimental verification of a finite element calculation of bundle mode shapes and frequencies is described. The calculated effect of asymmetric sub-span lengths on the critical wind speed of a twin bundle is demonstrated. It is argued that the apparent success of some spacer dampers may be attributable to the unequal sub-spans used in their installation rather than their enhanced damping properties. An approach to spacer testing based on estimates of annual numbers of cycles of oscillation and calculated mode shapes is considered.

@conference{allnutt1980control, abstract = {The physics of sub-span oscillation is discussed in simple terms in order to elucidate the role of the various mechanical parameters. The results of a limit cycle analysis of a simple model show that mechanical damping has a relatively small effect on motio~ amplitude until high values of damping are reached. Tests on typical commercial twin spacer dampers, using a mechanically-excited, low level test line, show that suitably high values of damping are unlikely to be achieved. The effect of the ratios of certain bundle natural frequencies on the instability is shown to be of great importance ; the experimental verification of a finite element calculation of bundle mode shapes and frequencies is described. The calculated effect of asymmetric sub-span lengths on the critical wind speed of a twin bundle is demonstrated. It is argued that the apparent success of some spacer dampers may be attributable to the unequal sub-spans used in their installation rather than their enhanced damping properties. An approach to spacer testing based on estimates of annual numbers of cycles of oscillation and calculated mode shapes is considered.}, added-at = {2020-04-27T17:34:14.000+0200}, author = {ALLNUTT, J and PRICE, S and TUNSTALL, M}, biburl = {https://www.bibsonomy.org/bibtex/2ca375ba4e9bc4562c13a6e5d21af8544/chkokalis}, interhash = {292e1eef3217186d53be881b891f20dc}, intrahash = {ca375ba4e9bc4562c13a6e5d21af8544}, keywords = {Aerodynamics Bundle Conductor Damping Oscillation Spacer Sub-span}, timestamp = {2020-05-06T13:11:44.000+0200}, title = {THE CONTROL OF SUB-SPAN OSCILLATION OF MULTI-CONDUCTOR BUNDLED TRANSMISSION LINES}, year = 1980 }