Andrew Jenike was recently
recognized as a pioneer in the field of powder and bulk engineering.

John
Carson receives the award on behalf of the Jenike family from Professor Alan
Roberts, representing the British Materials Handling Board.
We
have all heard
of Man of the Year awards, but this one is different. In recognition of
outstanding contributions that transformed the storage and handling of bulk
solids from an empirical industry to a science, the British Materials Handling
Board recently honored Andrew Jenike, Ph.D., as the leading Bulk Technology
Pioneer of the Twentieth Century at the American Institute for Chemical
Engineers Annual Meeting in Salt Lake
City, Utah. Jenike is
one of the true pioneers in the field of powder and bulk engineering, which has
numerous applications in the ceramic industry and beyond.

Jenike was instrumental to the understanding of solids flow through silos...
Background
Andrew Jenike was born in Poland in 1914
and graduated in 1939 from Warsaw Polytechnic Institute with a bachelor’s of
science degree in mechanical engineering. After graduation, he entered the
Polish Army and served with distinction as an officer in World War II. Soon
after he entered the army, Poland
was overrun by the Nazis and the Russians.
One day, Jenike found himself at the top of a hill. Advancing on one side of
the hill were the Nazis, while the Russians made their approach on the other
side of the hill. His unit commander said it was time to leave, so Jenike fled
on foot through Eastern Europe and eventually made it to England. He
found employment there and attended the University of London,
where he received his doctorate in structural engineering in 1949.
While in England,
he also met and married a British woman named Una. The couple immigrated to Canada and then to the U.S., eventually settling in Salt Lake City. Along the way, Jenike worked
for several engineering design firms as a mechanical and structural engineer.
Two sons, Michael and Ian, were born during this time.

...bins...
As Jenike approached his mid- to late-30s, he
began to get restless. He wanted to do something unique, something that would
set him apart and would be worthwhile. He started by reading and collecting
articles on every conceivable subject, going to the library every night and
every weekend. He put the information he collected into a series of folders
arranged by topic. Eventually, he identified about 40 different topics of
interest. He constantly poured over these folders, trying to decide which topic
would provide him with the opportunity to make a significant contribution.
On April 16, 1953 (his 39th birthday), Jenike made his decision. The
topic he chose was the design of bins and hoppers for the storage and flow of
bulk solids. Up to that time, the design of this equipment was mostly a black
art. Most hoppers were either 45º or 60º, simply
because those were the measurements of common triangles that all engineers
carried around with them. No one gave much thought to the material being
stored.
Once Jenike made his decision, he promptly threw away box after box that he had
collected on the other topics he had considered. He wanted nothing to interfere
with his decision, no looking back. (It is interesting to note that one of the
topics that didn’t make his cut was computing.)

...and feeders.
Jenike approached the National Science Foundation
and other groups for funding and was told that, while his work was a worthwhile
area of research, he would need an affiliation with a college or university
before he could be funded. Since he was living in Salt Lake
City, he went to the University
of Utah with the
following proposal: “If you will put me on your staff, I will get all of the
funding. It won’t cost you a penny.” The university accepted the deal, and
Jenike spent seven years there developing basic theories and test equipment. He
set forth design procedures in “University of Utah Engineering Experiment
Station Bulletins 108 and 123.”
One key contributor to Jenike’s success in developing the basic theories
of solids flow came from an unlikely source. While on a trip back to his native
Poland,
he came across a Polish translation of Sokolovskii’s now-famous
Statics of Soil Media. At
the time, this book had just been published in Russian and had not yet been
translated into English. Jenike immediately recognized that Sokolovskii’s
concept that soil stress could vary directly in proportion to the distance from
a point fit nicely with some crude bin pressure measurements that he had
conducted using water-filled diaphragms. This gave rise to his Radial Stress
Field concept.
During his period at the University
of Utah, Jenike had a
number of graduate students working for him, including Jerry Johanson. In 1962,
Johanson finished his doctorate and went to work at U.S. Steel Research. Jenike
decided that the time had come to enter full-time consulting, and he moved his
family to Winchester, Mass. Four years later, Johanson joined him
and they formed Jenike & Johanson. Jenike was president of the firm until
he retired in 1979. After that time, he conducted research for about eight
years until a serious automobile accident prevented him from working.

Funnel flow and mass flow.
Contributions to Industry
The contributions of Andrew Jenike in filling the void in our
understanding of the rheology of particulate
solids in gravity flow were thorough and comprehensive. His first important
step was to recognize that the inability to predict the design requirements for
bulk storage containers that would discharge reliably was a handicap of immense
importance to all industries that handle bulk solids, including ceramics, chemical
processing, mining, food and more. Applying himself to solving this puzzle,
Jenike produced a theory of converging flow that represented the key parameters
and process conditions.
He next developed an instrument with which to
quantify the relevant factors of a given product, and then constructed a design
methodology to interpret these values and produce a geometry for a bulk storage
vessel that would guarantee flow and discharge the contents reliably. His
pioneering work, published in “Bulletin 123 of the Utah Experimental Station”
in 1964, remains the most quoted reference of all papers published in the field
of bulk technology and solids rheology.
Andrew Jenike was a visionary and, indisputably, the founder of the modern
theories and industrial applications of bulk solids handling. He developed a
theory to fulfill a practical need, and he approached his work with enthusiasm
and focus. He changed the way we design and build storage and processing
vessels for bulk solids in a very revolutionary way-from an empirical technique
to a formal engineering procedure with a predictable outcome. The applications
of his work go well beyond small bin designs to include bottom reclaim
stockpiles, mammoth silos, purge columns, moving bed reactors, in-bin blenders and
more.
Thousands of silos have been built based on Jenike’s method of design, and this
has improved the economy of industry by perhaps the order of billions of
dollars every year worldwide. He has made a deep impact on our understanding of
how particular solids behave during flow, and our understanding of silo flow
has been changed forever.
In the glass and ceramic industries, Jenike’s approaches have influenced the
design and effectiveness of solids handling and batch preparation facilities
throughout the world. Engineering firms have adopted design strategies for fine
and cohesive powders to achieve reliable flow. Equipment manufacturers have
benefited through the inclusion of features that minimize problems while
delivering the desired throughput. Even when problems
have arisen at operating facilities, such as a loss of batch homogeneity or
furnace feed reliability, Jenike’s strategies have been deployed as
modifications to help systems realize their economic potential.

Using bench-scale tests to measure flow properties.
Making a Difference
“Some advances are made by serendipity, but the more radical improvements usually come about by dedicated
study, based upon insight and a fundamental analysis of the underlying
factors,” said Lyn Bates, director of the British Materials Handling Board in a
tribute accompanying the naming of Andrew Jenike as the leading Bulk Technology
Pioneer of the Twentieth Century. “The result of Jenike’s outstanding work was
to change the design of bulk storage hoppers, silos, and other storage and
processing vessels from an empirical technique to a formal engineering
procedure with a predictable outcome.”

In addition to this recent award, Jenike received the Humboldt
Scholarship in 1976. In 1989, he was elected Fellow of the American Society of
Mechanical Engineers (ASME), and in 1993 he received the Solids Handling Award
from the Institute
of Mechanical Engineers
(the first non-UK person to do so). He received the Particle Technology Award
from the American Institute of Chemical Engineers (AIChE) in 1998.
Fundamental phenomena like mass and funnel
flow were bound to be discovered sooner or later by someone equipped to make
the necessary observations. However, it was Andrew Jenike who first made the
discovery, and he formulated vital theories in his own practical way. He
initiated a completely new field of research that will continue to challenge
new generations of scientists for many years to come.
For more information, contact Jenike & Johanson, Inc. at 400
Business Park Dr., Tyngsboro, MA 01879; (978) 649-3300; fax (978) 649-3399;
e-mail the authors at jwcarson@jenike.com or rbarnum@jenike.com; or visit www.jenike.com. Links