* Economic imbalances, yuan's future on summit agenda

* N. Korea, Iran, climate pact also topics for talks

* Chinese paper says nations like "conjoined twins"

* Obama "town hall" event may raise Tibet, rights

By Caren Bohan and Patricia Zengerle

SHANGHAI, Nov 16 (Reuters) - U.S. President Barack Obama faces tensions with China over trade and Tibet on his first visit to the emerging superpower for a summit that will grapple with economic imbalances and the future of the yuan currency.

Obama arrived in Shanghai, China's commercial hub, late on Sunday and is due to meet city officials and hold a town hall-style meeting with young people before heading to Beijing later on Monday.

Chinese state-run Internet sites have asked the public for questions to quiz Obama at the youth meeting, and many urged him to explain if he plans to meet the Dalai Lama, the exiled Tibetan leader whom Beijing brands a separatist.

These events will be a warm-up for Obama's summit with President Hu Jintao in the capital on Tuesday that will cover trouble-spots such as North Korea and Iran, and efforts to forge a new climate pact.