The 32-year-old forward, who has signed a two-year deal following his release from Newcastle, passed his medical on Monday afternoon and reported for training as Blues started their pre-season preparations under Clark, who took the reins from Chris Hughton towards the end of June.
Lovenkrands' contract with Blues includes an option for a further year, and Clark welcomed the arrival of the experienced campaigner.
He told the official club website, bcfc.com: "He did very well for Newcastle, has scored goals at this level and he played a huge part in getting them promoted from this division, actually winning the league."
He added: "When I spoke to him about the move he made a decision very quickly. Once we got an agreement, he's bringing his family down, moving to the area, doing that very, very quickly as well so it shows you he's very committed to the job in hand and that can only be good for us and the supporters.
"I have got to see him quite a bit and he's a very popular guy as well. He has a good work ethic and he ticked all the boxes for me in terms of not just being a good player but by being a good character."
The Denmark international, a target of both previous Blues bosses Hughton and Alex McLeish, was released by Newcastle earlier this summer having scored 26 goals in 85 appearances for the Magpies over two spells since 2009.
He first moved to Britain in 2000 when he joined Rangers, ending a six-year spell north of the border with a switch to German side Schalke, whom he represented for three seasons before linking up with Newcastle.