- Scientific computing
- Monte Carlo methods
- Numerical solution of stochastic equations
- Statistical mechanics
- Turbulent transport
- Fluid dynamics
The research of David J. Horntrop has focused on the development and numerical simulation of stochastic models of physical phenomena for problems ranging from materials science to fluid dynamics. His studies of turbulent diffusion were based on random field models for the advection of passive scalars and involved asymptotics, stochastic analysis, and the creation of novel wavelet-based Monte Carlo numerical schemes for the simulation of random fields.