Simulations of flow and heat transfer around deforming objects require the accurate resolution of the moving interface. An approach that combines the Hybrid Immersed Boundary Method (HIBM) for handling complex moving boundaries and the Material Point Method (MPM) for resolving structural stresses and the movement of the deformable body is presented here. In the HIBM, a fixed Eulerian, curvilinear grid is generally defined, and the variable values at grid points adjacent to a curvilinear boundary arc interpolated to satisfy the boundary conditions. The MPM is used to solve equations of the solid structure (stresses and deflection) and communicates with the flow equations through appropriate interface-boundary conditions. As a validation of the new approach for heat transfer problems, flow and heat transfer past a rigid and deforming isothermal sphere is simulated. Predictions agree well with published results of Nusselt number for flow past a rigid sphere. (c) 2008 Elsevier Ltd. All rights reserved.