Hi Samid,
You cannot disable logging completely like in Oracle database. However, you can use circular logging instead of archival logging to avoid having to archive logs and also prevent logs from accumulating in the active log directory. This also means that you will loose the ability to do a point-in-time recovery and will only be able to do a version recovery.
In addition to commands shared above you need to execute one more command
db2 update db cfg for <SID> using logretain off
Hope this helps.
Regards,
Deepak Kori