Transient Flow Visualization in a Lexmark Printer

Project Sponsor: Lexmark International Inc.

Matt CasavantNor Izzati Nordin

Wan Afeek Wan AliGuy Davis

Lexmark Corporate Background Information• Lexmark was launched in 1991 and the company is known for developing

manufacturing, and supplying printing solutions.• Divided into 2 divisions

1) Consumer Printer Division (CPD)2) Printing Solutions & Services Division (PS&SD)

• Environmentally Conscious - Actively searches and uses environmental

friendly products.

Specific Engineering Contact• Mr. Kent Ubellacker (8 patents from 1997-2007 )

Problem Statement1. Print Defect

- Small ink droplets are blown away by the air flow of the print head as it moves left and right.

- The small particle does not hit the target but instead creates “veins” (below) on the paper.

Problem Statement Continued

2. Dirty Printer

- Small liquid particles (1.1-1.5 nanograms) mix with air flow due to the print head movement and end up misting the inside surface of the printer.

Empirical Problem Statement• Use the Vanderbilt water tunnel (thus choosing water as the fluid medium

due to the ability to dye flow patterns) to study flow over a container to better understand the flow disturbances it creates.

• This will then allow for inconsistent print patterns such as veins to be corrected.

Broad Project Tasks• Improve accuracy of inkjet printhead through slight print head shape

change

• Improve visualization of air flows near the ejectors of the printhead

• Demonstration of how those air flows can be changed

(study major drivers that create the situation)

• Some study of physical geometry or features which may help the problem(baffles, obstructions etc).

• Combine knowledge of Fluid Mechanics and trial and error observation to improve flow predictability

Specific Tasks/Problems

1. Present experimental procedure to Prof. Anilkumar

2. Issues with mounting print head and carrier in water tunnel (consult TA)

3. Attain image processing software and gain familiarity with it

4. Carrier already in production; thus overall sizes and shapes can not be altered

5. Determination of “add-on” material (considering hardening putties)

6. Issues with simulating paper in water tunnel (boundary layer)

7. Finding water tunnel speed in accordance with Reynolds number of print head in air

• Image Enhancement– Contrast

• Capture & Compare

• Matlab

Image Processing

Gantt Chart

Needs• Ink particles to hit target

(accuracy)

• Veins to go away

• Clean printer (no small flying ink particles)

• Accomplished through laminar flow between printhead and paper

• Lack of change to basic structure of carrier

Wants• Inexpensive

• Simplicity in solution

• Less mess

• Environmentally friendly

• Easily manufactured

Questions/Comments?