The roughness of the deposited particle layer on surfaces driven by particle-turbulence interactions

Abstract

The purpose of this action is to provide a FY25 CR2 initial funding increment in the amount of $20K.--Approved for Public Release. This proposal outlines an experimental program to systematically investigate the physics governing particle deposition on surfaces in gas turbine engines. Particulate deposition on turbine blade surfaces reduces aerodynamic efficiency and component life, motivating a fundamental understanding of the deposition process. A key focus is linking the heterogeneous roughness patterns that emerge from deposition to the near-wall turbulence structures and particle dynamics within the turbulent boundary layer. Two complementary experimental facilities are proposed utilizing optical diagnostics to capture the transient deposition process. An ambient temperature vertical channel enables electrostatic charging of seeding particles to explore particle-wall interactions. Preliminary results quantify the increase in deposition velocity and near-wall particle fluctuations with increased particle charge. A high-temperature facility replicates realistic particle sticking behavior up to particle melting point. Proposed measurements aim to characterize deposition nucleation, growth stages, and the evolving coupling between the deposited roughness and near-wall coherent structures. Planned diagnostics include time-resolved particle tracking, surface topology reconstruction using laser grids on deposit structures. The systematic investigation targets fundamental mechanisms to predict heterogeneous deposition patterns and motivate mitigation strategies for particulate fouling in turbomachinery.

Document Details

Document Type
DoD Grant Award
Publication Date
Mar 12, 2025
Source ID
N000142512194

Entities

People

  • Rui Ni

Organizations

  • Johns Hopkins University
  • Office of Naval Research
  • United States Navy

Tags

Fields of Study

  • Physics

Readers

  • Aerosol Science/Aerosol Physics
  • Computational Fluid Dynamics (CFD)
  • Fluid Mechanics and Fluid Dynamics.

Technology Areas

  • Directed Energy
  • Directed Energy - Pulsed-Laser Deposition