The Brown Marmorated Stink Bug (BMSB) Halyomorpha halys is an unwanted invasive species. Its entry and establishment in New Zealand would result in significant production impacts in the horticultural industry. Current BMSB traps are A4 size sticky panels with aggregation pheromone as a lure. These traps are affordable, but inefficient. A novel live trap has been proven ~7 times as efficient in a forest–vineyard margin in Italy. This trap has the lure in the trap chamber and self-orients to the wind. The present work used CFD to model pheromone transport, comparing the sticky panel to the new trap, and to a refined design suitable for mass production. The new trap produces a more concentrated plume than the panel traps. Pheromone dispersion is compared in three environments (flat plain, car yard and vegetation). The pheromone plume mixes more rapidly in vegetation. The current results use a coarse mesh, but guide further modelling and design refinement.