Transient two-dimensional negatively buoyant flow into a straight adiabatic baffle beneath an isothermal circular cylinder is numerically simulated. The surrounding fluid is considered infinite in extent and at constant temperature. Governing parameters are the baffle width and the offset of the entrance of the baffle beneath the center of the cylinder. Overall characteristics of the flow and entrainment of the surrounding fluid are found to be dependent on the baffle offset; however, the attachment length of the flow to the baffle wall is relatively insensitive to the offset. Heat transfer rates to the cylinder are calculated for various times for various baffle offsets. There is a weak dependence on baffle-offset distance with heat transfer rate.