Work Examples

Department of Mechanical Engineering
Knowledge. Innovation. Leadership. www.me.iastate.edu
Examples of My Work
Joshua B. Drake
Ph.D Candidate
Iowa State University
Ames, Iowa

Disclaimer
• This is a short overview of the work I have performed at Iowa State University as a Ph.D.
graduate assistant.
• The topics discussed here are technical in nature and require the reader have some knowledge
in the field.
• Most slides contain references to papers that have been or are currently in the process of being
published.

Fluidized Bed Reactor Design
• Helped to design two simple non-reactive cold flow fluidized bed reactors.
61 cm
30 cm
15 cm
Freeboard chamber
Reactor chamber
Aeration plate
Plenum
Air inlet
Pressure tap
Side air injection port
61 cm
30 cm
15 cm
10.2 cm 15.2 cm
a) b)
Fluidized bed

Fluidized Bed Reactor Air Flow
Control Design
• Designed a flow control system for fluidized bed reactors using a simple PID algorithm
developed in LabView.

X-ray Visualization
• Performed X-ray radiographic, stereographic, and computed tomography using a one of a kind
facility at Iowa State University.
• Analyzed various mechanical concepts of multiphase flows using non-invasive X-ray
techniques.
CsI phosphor screen &
CCD camera
Lead
shutters
Rotation ring
Test stand
15.2 cm fluidized bed reactor (in imaging region)
Image intensifier &
CCD camera
X-ray
sources
The X-ray facility [1] used to acquire data.

Tracer Particle Manufacturing
Development Techniques
• Developed a process to manufacture composite tracer particles for the analysis of biomass
circulation in a fluidized bed using X-ray imaging techniques.
An example showing how a high expansion two-part polyurethane foam was
combined with a spherical lead shot to make a spherical tracer particle in a cast [2].

Tracer Particle Manufacturing
Development Techniques Continued
Lead
shot
Polyurethane
foam
Fingernail
polish
Tracer particle
hemisphere
Completed tracer
particle
A completed composite tracer particle [2].

0
2
4
6
8
10
12
14
16
18
0 2 4 6 8 10 12 14
z-position[cm]
time [sec]
successfulhit
unsuccessfulhit
Top of static bed
Top of jets
X-ray Particle Tracking Velocimetry
Analysis
• Performed quantitative analysis of the 3D path traveled by a simulated biomass particle in
dynamic fluidized beds at low flow conditions.
The vertical position of a tracer particle over ~13 seconds in a dynamic
fluidized bed of 0.5-0.6 mm glass beads. The red dots indicate incorrectly
identified positions with an automated application [3, 4].
A false color enhanced radiograph of a tracer
particle (indicated by the white circle) in a
dynamic fluidized bed of 0.5-0.6 mm glass
beads [3, 4].

X-ray Particle Tracking Velocimetry
Analysis Continued
-8
-6
-4
-2
0
2
4
6
8
0 2 4 6 8 10 12 14
x-position[cm]
time [sec]
successfulhit
unsuccessfulhit
Reactorwall
Reactorwall
Reactorcenter
-8
-6
-4
-2
0
2
4
6
8
0 2 4 6 8 10 12 14
y-position[cm]
time [sec]
successfulhit
unsuccessfulhit
Reactor wall
Reactor wall
Reactor center
Horizontal tracer particle positions in the x- (left) and y-axis (right) over ~13 seconds in a dynamic fluidized bed of 0.5-0.6
mm glass beads [3, 4].

X-ray Imaging Analysis Software
Development
• Helped create unique software for analysis of X-ray imaging data using C++, C#, and MatLab.
The figure shows a vertical slice of an X-ray
computed tomography (CT) of a 0.5-0.6 mm
glass bead fluidized bed opened in Xrip (in
house software developed to analyze X-ray
images). This software can: acquire X-ray
radiographs, stereographs, and CT data in the
form of sinograms; reconstruct X-ray CTs;
perform post-processing calculations; and
export data to images and Excel workbooks.
3D CT images can be manipulated spatially
by vertically or horizontally slicing. Batch
processes can be scripted for large image
processing loads and calculations. The code
has been optimized and parallelized for fast
and efficient calculations.

Multiphase Flow Analysis
• Performed quantitative analysis of the repeatability for calculating the local time-average gas
void fraction in dynamic fluidized beds using X-ray CTs.
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0
GasHoldup[-]
r/R[-]
x-z Test 1 y-z Test 1
Glass Beads
D = 15.24 cm
Ug = 1.50Umf
Qs = 0.00Qmf
h = 0.50D
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0
GasHoldup[-]
r/R[-]
Glass Beads
D = 15.24 cm
Ug = 3.00Umf
Qs = 0.00Qmf
h = 0.50D
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0
GasHoldup[-]
r/R[-]
Glass Beads
D = 15.24 cm
Ug = 1.50Umf
Qs = 0.00Qmf
h = 1.00D
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0
GasHoldup[-]
r/R[-]
Glass Beads
D = 15.24 cm
Ug = 3.00Umf
Qs = 0.00Qmf
h = 1.00D
Ug = 1.5Umf Ug = 3Umf
h=0.5Dh=1D
Lines of local time-average gas void fraction taken from five tests in a 15.2 cm
diameter fluidized bed of 0.5-0.6 mm glass beads at heights of 0.5D (top) and 1D
(bottom) and superficial gas velocities of Ug = 1.5Umf (left) and 3Umf (right) [5, 6].

Multiphase Flow Analysis Continued
• Performed quantitative analysis of the local time-average gas void fraction uniformity in
dynamic fluidized beds using X-ray CTs.
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0
GasHoldup[-]
r/R[-]
15 deg 105 deg
30 deg 120 deg
45 deg 135 deg
60 deg 150 deg
75 deg 165 deg
90 deg 180 deg
Glass Beads
D = 15.24 cm
Ug = 1.50Umf
Qs = 0.00Qmf
h = 0.25D
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0
GasHoldup[-]
r/R[-]
15 deg 105 deg
30 deg 120 deg
45 deg 135 deg
60 deg 150 deg
75 deg 165 deg
90 deg 180 deg
Glass Beads
D = 15.24 cm
Ug = 3.00Umf
Qs = 0.00Qmf
h = 0.25D
Ug = 1.5Umf Ug = 3Umf
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0
GasHoldup[-]
r/R[-]
15 deg 105 deg
30 deg 120 deg
45 deg 135 deg
60 deg 150 deg
75 deg 165 deg
90 deg 180 deg
Glass Beads
D = 15.24 cm
Ug = 1.50Umf
Qs = 0.00Qmf
h = 0.75D
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0
GasHoldup[-]
r/R[-]
15 deg 105 deg
30 deg 120 deg
45 deg 135 deg
60 deg 150 deg
75 deg 165 deg
90 deg 180 deg
Glass Beads
D = 15.24 cm
Ug = 3.00Umf
Qs = 0.00Qmf
h = 0.75D
Side-air
injection
port
0°
90°
15°
30°
45°
60°
75°
165°
150°
135°
120°
105°
180°
x
y
Boss
Reactor
wall
The local time-average gas void fraction in a 15.2 cm diameter fluidized
bed of 0.5-0.6 mm glass beads at heights of h = 0.25D and 0.5D (top)
and h = 0.75D and 1D (Bottom) and superficial gas velocities of
Ug = 1.5Umf (left) and 3Umf (right) [5, 6].
This figure shows how gas void fraction
data was acquired for a 15.2 cm diameter
fluidized bed [5, 6]. An X-ray CT of the
dynamic fluidized bed was sliced through
the bed center vertically every 15° from 0°
to 165° revealing the local time-average gas
void fraction map in the bed at these
locations.

• Performed qualitative and quantitative analysis of the local time-average gas void fraction in
various materials at low flow conditions of varying fluidized bed diameters using X-ray CTs.
The figure presents qualitative gas void fraction
data for a 10.2 cm and 15.2 cm diameter fluidized
glass bead bed at a superficial gas velocity of
Ug = 1.5Umf. The first three columns correspond
to the 10.2 cm diameter bed, while the last three
columns denote the 15.2 cm diameter bed. Each
column contains two round horizontal CT slices
located above and two below each rectangular
vertical CT slice that bisects the bed through the
side-air injection port. Each column shows side-
air flow conditions at particular heights (h =
0.25D, 0.5D, 0.75D, and 1D) above the aerator.
The heights of each horizontal slice are indicated
on the vertical slices by dashed lines, where the
top two images (h = 1D and 0.75D) correspond to
the top two dashed lines and the bottom two
images (h = 0.5D and 0.25D) to the bottom two
dashed lines. Side-air was injected through a port
on the reactor side indicated by a small dark box
at the right of the vertical slices near the bottom
dashed line for both geometries.

0.2
0.3
0.4
0.5
0.6
0.7
0.8
-1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0
GasHoldup[-]
r/R [-]
Corncob, D = 10.2 cm Corncob, D = 15.2 cm
Walnut Shell, D = 10.2 cm Walnut Shell, D = 15.2 cm
Glass Beads, D = 10.2 cm Glass Beads, D = 15.2 cm
Ug = 1.5Umf
Qs = 0Qmf
h = 0.75D
The local time-average gas void fraction in a 10.2 cm and 15.2 cm fluidized bed of 0.5-
0.6 mm crushed corncob, ground walnut shell, and glass beads at a superficial gas
velocity of Ug = 1.5Umf and a height of 0.75D [7].

Annular local time-average gas void fraction contour plots in a 10.2 cm fluidized bed of 0.5-0.6 mm glass beads, crushed
corncob, and ground walnut shell at a superficial gas velocity of Ug = 2Umf [8]. This data is highly valuable as a benchmark
for computational fluid dynamic simulation validation and comparison.
• Performed qualitative and quantitative analysis of annular local time-average gas void fraction
in various materials at low flow conditions of varying fluidized bed diameters using X-ray
CTs.

• Performed qualitative and quantitative analysis of cavitation in a plastic butterfly valve using
X-ray CT’s [9].
79 gpm
58 psi
y-zprojectionx-zprojection
N S
W E
Empty
95 gpm
74 psi
95 gpm
95 psi
95 gpm
109 psi
1.0
0.0
0.1
0.2
0.3
0.5
0.4
0.6
0.7
0.9
0.8
GasVoidFraction

References
[1] Heindel TJ, Gray JN, Jensen TC. An X-ray system for visualizing fluid flows. Flow Measurement and Instrumentation.
2008;19(2):67-78.
[2] Drake JB, Kenney AL, Morgan TB, Heindel TJ. Developing tracer particles for X-ray particle tracking velocimetry. ASME-
JSME-KSME Joint Fluids Engineering Conference. Hamamatsu, Shizuoka, Japan: ASME Press, Paper AJK2011-11009 2011:8.
[3] Drake JB, Franka NP, Heindel TJ. Developing X-ray particle tracking velocimetry for applications in fluidized beds. ASME
International Mechanical Engineering Congress and Exposition. Boston, MA, USA: ASME Press, Paper IMECE2008-66224
2009:379-86.
[4] Drake JB, Tang L, Heindel TJ. X-ray particle tracking velocimetry in fluidized beds. ASME Fluids Engineering Division
Summer Conference. Vail, CO, USA: ASME Press, Paper FEDSM2009-78150 2009:1733-42.
[5] Drake JB, Heindel TJ. Repeatability of gas holdup in a fluidized bed using x-ray computed tomography. ASME Fluids
Engineering Division Summer Conference. Vail, CO, USA: ASME, Paper FEDSM2009-78041 2009:1721-31.
[6] Drake JB, Heindel TJ. The repeatability and uniformity of 3D fluidized beds. Powder Technology. 2011; 213(1-3): 148-54.
[7] Drake JB, Heindel TJ. Local time-average gas holdup comparisons in cold-flow fluidized beds. Chemical Engineering Science.
2011 (To Appear).
[8] Drake JB, Heindel TJ. Comparisons of annular hydrodynamic structures in 3D fluidized beds using X-ray CT. Journal of Fluids
Engineering. 2011 (In Review).
[9] Heindel TJ, Jensen TC, Drake JB, McCormick N, Riveland ML. 3D X-ray CT imaging of cavitation from a butterfly valve. 7th
International Conference on Multiphase Flow. Tampa, FL, USA: Paper 1746-2010.

Work Examples

Recommended

Recommended

More Related Content

Similar to Work Examples

Similar to Work Examples (20)

Work Examples