NEXT MEETING
(noon)_______________________________________________________
Location: Cellar Restaurant, 2 Union Square, Chattanooga, TN 37402 (basement of Tallan Building at M.L.King & Carter Streets)
Monday, May 16: "Ozone and Fine Particulates" - Errol Reksten, Chattanooga Air Pollution Control Bureau
Errol Reksten from the Chattanooga Air Pollution Control Bureau will discuss ozone and fine particulates. He will talk about what is being done in Southeast Tennessee and North Georgia to reduce ozone and fine-particulate emissions, as well as plans for future steps. Reksten says that based on new, more stringent criteria, the federal government recently identified Hamilton County and 17 other Tennessee counties as non-attainment areas for ozone. He defines smog as a mixture of various pollutants, including ground-level ozone, which occurs naturally and from reactions among chemicals produced by the burning of fossil fuels. Reksten says fine particulates include dust, soot and other tiny bits of solid materials released into the air. He says particulates are produced by many sources, including the burning of diesel fuel by trucks and buses, incineration of garbage, mixing and applying fertilizers and pesticides, road construction, industrial processes, and fireplaces and woodstoves.
OUR PREVIOUS MEETING _______________________________________________________
Location: Cellar Restaurant, 2 Union Square, Chattanooga, TN 37402 (basement of Tallan Building at M.L.King & Carter Streets)
Monday, May 16: "Ozone and Fine Particulates" - Errol Reksten, Chattanooga Air Pollution Control Bureau
Errol Reksten from the Chattanooga Air Pollution Control Bureau will discuss ozone and fine particulates. He will talk about what is being done in Southeast Tennessee and North Georgia to reduce ozone and fine-particulate emissions, as well as plans for future steps. Reksten says that based on new, more stringent criteria, the federal government recently identified Hamilton County and 17 other Tennessee counties as non-attainment areas for ozone. He defines smog as a mixture of various pollutants, including ground-level ozone, which occurs naturally and from reactions among chemicals produced by the burning of fossil fuels. Reksten says fine particulates include dust, soot and other tiny bits of solid materials released into the air. He says particulates are produced by many sources, including the burning of diesel fuel by trucks and buses, incineration of garbage, mixing and applying fertilizers and pesticides, road construction, industrial processes, and fireplaces and woodstoves.
OUR PREVIOUS MEETING _______________________________________________________
May 9: "Aerodynamic Drag Reduction of
Heavy Vehicles" - Dr. David Whitfield, UTC SimCenter
Dr. Whitfield told us that the UTC SimCenter staff
and U.S. Xpress joined into application-driven research that has been in
progress for many years and is funded by the U.S. Department of Energy to reduce
the aerodynamic drag on heavy vehicles. Conducting this research involves
the use of complex equations for analysis of wind drag and other forces at many
nodes or spaces simulated by creating a computerized web-like grid around the
form to be studied. Depending on the specific problem, there may be from
six to 18 equations at each grid node at each time step. This can result
in the computation of millions of calculations. Some of the equations
include Time-Dependent Navier-Stokes Equation that describe how the velocity,
pressure, temperature, and density of a moving fluid are related.
Different equations for solving shear stress such as two-equation turbulence
models are used. Some calculations they have added to the study are
for:
* Dual tires
* Tires with tread
* Dual tires in tandem
* Full truck with and without rotating tires
* Full truck in a wind tunnel vs. full truck in free air (real solution)
* Splash and spray from a rotating tire
With the need for such extreme computational requirements, a robust computer is a must. The SimCenter now has the 8th largest computer among U.S. Universities, the 29th largest in the United States and the 42nd largest in the world (based on November 2004 data). They have over 800 processors connected together and working jointly to solve equations for this and other projects (some classified). They already had experience modeling rotating round things from their work in the aircraft industry and experience in drag reduction from their work on submarine designs. The challenge in modeling a truck is that the round rotating tires also have "squash" where they rest on the pavement. Dr. Whitfield told us their equations not only account for the truck moving through air, but also the yaw created by cross winds. The three main areas where drag might be reduced is the gap between the cab and the trailer, the underbody and the wheels, and the base or end of the trailer. But this doesn't rule out small drag reduction changes like making the driver's outside door handle flush with the cab. Dr. Whitfield told us this could reduce drag by 1% at high speeds. The gap between the cab and the trailer must be there in particular lengths to allow the truck to turn. Mud flaps can reduce drag more if they are placed closer to the rear of the truck trailer, but they may be knocked off or damaged when the truck backs up to a loading dock. Some design changes may cause other problems. Dr. Whitfield told us that If they reduce the drag around the tires, then the brakes may overheat in some situations. US Xpress is helping UTC to consider only practical design changes in their models to reduce drag.
FUTURE MEETINGS (noon in the Tallan Cellar Restaurant unless another time or location is indicated) __________
Monday, May 23: "Mass Notification of Emergency Conditions" - Vic Humm, Safety Technology International, Inc.
May 30: No Meeting - Memorial Day
Saturday, June 4: CEC Summer Social -- Pizza in the Park, 10 am to 2 pm
(Location: Chester Frost Park, Pavilion #3)
Monday, June 6: “Advances in Refining Coal for Power Production" - Dale Bradshaw, Advanced Coal Technology (ACT)
June 13: No meeting because of Joint Meeting on June 15 with the Chattanooga Technology Council
Wednesday, June 15: "Situational Awareness System for Chattanooga Metropolitan Airport Emergencies" Ken Martin, National Safe Skies Alliance
Joint meeting of Chattanooga Technology Council and Chattanooga Engineers Club
Location and time of lunch to be announced.
Monday, June 20: "New Chattanooga State Incentives" Dr. James L. Catanzaro
Monday, June 27: (TBA by Judy Driggans)
July 4: No meeting - Independence Day
Monday, July 11: 12:30 pm Tour of Chattanooga Group, Inc., a local manufacturer of medical equipment and a division of Encore Medical Corp.
WHERE WE MEET _________________________________________________________
We will usually meet at the Cellar Restaurant in the basement of the Tallan Building at the corner of M. L. King Blvd. and Carter Street. Lunch at the Cellar Restaurant is a hot buffet for $10 and the meal is available at 11:30 a.m. Parking is available free at the Days Inn across Carter Street, but you will need a note in your windshield that you’re attending the Chattanooga Engineers Club meeting. You may also park one hour free in the garage behind the Tallan building if you have your ticket stamped in the Cellar Restaurant. The second Monday of each month will be at a location to be announced.
QUESTIONS, SUGGESTIONS? ______________________________________________
If you have any questions or suggestions about program items please contact Judy Driggans at 423-751-7616 or by email at jdriggans@comcast.net. You can find references to other Chattanooga Engineers Club members at our web site: www.ChattanoogaEngineersClub.org.
* Dual tires
* Tires with tread
* Dual tires in tandem
* Full truck with and without rotating tires
* Full truck in a wind tunnel vs. full truck in free air (real solution)
* Splash and spray from a rotating tire
With the need for such extreme computational requirements, a robust computer is a must. The SimCenter now has the 8th largest computer among U.S. Universities, the 29th largest in the United States and the 42nd largest in the world (based on November 2004 data). They have over 800 processors connected together and working jointly to solve equations for this and other projects (some classified). They already had experience modeling rotating round things from their work in the aircraft industry and experience in drag reduction from their work on submarine designs. The challenge in modeling a truck is that the round rotating tires also have "squash" where they rest on the pavement. Dr. Whitfield told us their equations not only account for the truck moving through air, but also the yaw created by cross winds. The three main areas where drag might be reduced is the gap between the cab and the trailer, the underbody and the wheels, and the base or end of the trailer. But this doesn't rule out small drag reduction changes like making the driver's outside door handle flush with the cab. Dr. Whitfield told us this could reduce drag by 1% at high speeds. The gap between the cab and the trailer must be there in particular lengths to allow the truck to turn. Mud flaps can reduce drag more if they are placed closer to the rear of the truck trailer, but they may be knocked off or damaged when the truck backs up to a loading dock. Some design changes may cause other problems. Dr. Whitfield told us that If they reduce the drag around the tires, then the brakes may overheat in some situations. US Xpress is helping UTC to consider only practical design changes in their models to reduce drag.
FUTURE MEETINGS (noon in the Tallan Cellar Restaurant unless another time or location is indicated) __________
Monday, May 23: "Mass Notification of Emergency Conditions" - Vic Humm, Safety Technology International, Inc.
May 30: No Meeting - Memorial Day
Saturday, June 4: CEC Summer Social -- Pizza in the Park, 10 am to 2 pm
(Location: Chester Frost Park, Pavilion #3)
Monday, June 6: “Advances in Refining Coal for Power Production" - Dale Bradshaw, Advanced Coal Technology (ACT)
June 13: No meeting because of Joint Meeting on June 15 with the Chattanooga Technology Council
Wednesday, June 15: "Situational Awareness System for Chattanooga Metropolitan Airport Emergencies" Ken Martin, National Safe Skies Alliance
Joint meeting of Chattanooga Technology Council and Chattanooga Engineers Club
Location and time of lunch to be announced.
Monday, June 20: "New Chattanooga State Incentives" Dr. James L. Catanzaro
Monday, June 27: (TBA by Judy Driggans)
July 4: No meeting - Independence Day
Monday, July 11: 12:30 pm Tour of Chattanooga Group, Inc., a local manufacturer of medical equipment and a division of Encore Medical Corp.
WHERE WE MEET _________________________________________________________
We will usually meet at the Cellar Restaurant in the basement of the Tallan Building at the corner of M. L. King Blvd. and Carter Street. Lunch at the Cellar Restaurant is a hot buffet for $10 and the meal is available at 11:30 a.m. Parking is available free at the Days Inn across Carter Street, but you will need a note in your windshield that you’re attending the Chattanooga Engineers Club meeting. You may also park one hour free in the garage behind the Tallan building if you have your ticket stamped in the Cellar Restaurant. The second Monday of each month will be at a location to be announced.
QUESTIONS, SUGGESTIONS? ______________________________________________
If you have any questions or suggestions about program items please contact Judy Driggans at 423-751-7616 or by email at jdriggans@comcast.net. You can find references to other Chattanooga Engineers Club members at our web site: www.ChattanoogaEngineersClub.org.