Hennepin County Medical Center announced Friday it will open a new medical simulation center, where health care workers can practice techniques on high-tech mannequins and interact with actors playing the role of patient. The 10,000-square-foot center, located on the lower level of Minneapolis-based HCMC's Level 1 trauma center, will open Jan. 7. HCMC said it expects to train about 20,000 people each year at the facility. There are several simulating health care learning centers in the Twin Cities,…