Austin Schenk, Brigham Young University
Due to significant advancements in electric motors and battery technology, electric propulsion has recently become a viable means for powering aircraft. With efficiencies of over twice that of standard combustion engines, specific power outputs of over four times, and the ability to increase the number of motors with little to no penalty in weight or efficiency, a whole new area of aircraft propulsion has been opened. Non-traditional design configurations can now be considered. One key non-traditional design consideration is distributed electric propulsion (DEP), which is the potentially beneficial concept of densely distributing multiple motors and propellers across the main lifting surface to increase lift. In this configuration propellers are located much closer to each other and complex propeller on propeller interactions are introduced. While these interactions have been characterized for vertical flight (or hovering) they have not been characterized for forward flight. By running multiple computational fluid dynamic (CFD) simulations across a range of separation distances we will be able to plot the propeller on propeller interaction as a function of separation distance. Fitting this data will give us an approximation of the flow characteristic and will be a starting point to understand these complex interactions. By building on these results and creating a mathematical model, we will be able to optimize the separation distance and design more efficient propulsion configurations. A validated CFD model has already been created and our preliminary results show promise of a significant separation-interaction correlation. We expect to arrive at a two dimensional surrogate model based on the thrust coefficient and the separation distance.