Date of Award

Fall 2020

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Mechanical Engineering

First Advisor

Stango, Robert

Abstract

Bristle blasting is a novel method that is rapidly gaining widespread acceptance among engineers and practitioners in the surface preparation industry. This process contains the use of a specially designed wire bristle tool that is precisely tuned to the spindle speed of a power tool that rotates at approximately 2,500 rpm. That is, the principle of operation is based upon synchronized/repeated impact and rebound of bristle tips with the target surface, leading to a multitude of impact craters that remove corrosion, expose fresh substrate material, and generate anchor profile. Hence, it is important to develop a model to research the crater depth generated during this wire impact process. The first portion of the current research is concerned with building a mathematical model, based on rigid body impact mechanics. The generalized impulse-momentum principle is used to analyze the impact process. The impact process is divided into compression phase and restitution phase. During the impact process, the concept of coefficient of restitution, which is defined based on the concept of energy, is implemented into this impact process. To validate the mathematical model, two case studies are examined. The first study demonstrates that by degenerating the model, a solution can be recovered that has been posted in the literature. The second study refers to a classic double pendulum problem that has been solved and shows that the current model can be modified to recover the solution posted in the literature. The second portion of this research is to investigate the crater depth generated by this monofilament model. First, recently published experimentally measured impact data reported by other authors is used to help construct impacted data for the wire impact tool. Thus, a numerical/analytical model is finalized for obtaining the force history of the impact process. Finally, a modified Merchant material removal model is used to analyze the crater depth for various friction coefficient and impact angles. This systematic analysis of the monofilament model of the wire impact tool represents a first step for providing valuable insight into both the design and operation of bristle tools that rival grit blasting processes.

Included in

Engineering Commons

Share

COinS