var controls = map.getControlsByClass('OpenLayers.Control.Navigation');
for(var i = 0; i < controls.length; ++i)
{
controls[i].disableZoomWheel();
}
Reference: Click Here
var controls = map.getControlsByClass('OpenLayers.Control.Navigation');
for(var i = 0; i < controls.length; ++i)
{
controls[i].disableZoomWheel();
}
Reference: Click Here