A two-dimensional computational scheme for simulating particle dispersion and deposition onto a cylinder in cross-flow was developed. RNG k-ε model was used to simulate the mean turbulent flow fields. The computational model predictions for particle deposition velocity between parallel plates showed good agreement with an empirical correlation befitting such geometry. Qualitative comparison showed that thermophoretic effect is more pronounced in duct flow than in cross-flow. For Stokes number, Stkc > 0.1 simulation results for a cylinder, rectangle and trapezoid in cross-flow are in good agreement. For Stkc < 0.1 geometry of the obstacle and turbulence effect play significant role in the net deposition. Simulations with constant particle size showed all the three deposition regimes by just varying the fluid velocity. Diffusion and residence time of the particle might explain this. Comparison of the results with some experimental results, for the similar geometry, is discussed in a companion paper.