ENGR 340 Wind Energy & Transportation (Part II) Nadia Gkritza CCEE

09-29-2011

What is going to happen if you followed a truck moving a wind turbine component up to a hill?

http://www.youtube.com/watch?v=8J8wrorY4G8&feature=related

How long will it take you to pass a truck carrying a wind turbine blade? http://www.youtube.com/watch?v=Q_Qp_DasGo0

Vehicle PerformanceWhy vehicle performance important?Determines all highway design and traffic operationsDefines how transportation engineers must react to advancing vehicle technologiesThe single most important factor in defining the tradeoff between mobility (speed) and safety

Forces acting on a road vehicle

Power required to overcome air resistance

What would you guess the drag coefficient of an Audi S4?

1. 0.25 2. 0.30 3. 0.37 4. 0.40 5. 0.47 6. 0.57

What would you guess the drag coefficient of a 2005 Hummer H2?

1. 0.25 2. 0.30 3. 0.37 4. 0.40 5. 0.47 6. 0.57

What would you guess the drag coefficient of a 2007 Honda Insight?

1. 0.25 2. 0.27 3. 0.37 4. 0.40 5. 0.47 6. 0.57

Sources: Tire deformation (90%) Pavement penetration (4%) Friction, other sources (6%)

Coefficient of rolling resistance:

frl = coefficient of rolling resistance and is unit less, and

V = vehicle speed in ft/s (m/s).

Example Problem

Solution

Figure . Performance Curves for Standard Trucks (200 lb/hp)Source: Highway Capacity Manual 2000. Copyright, National Academy of Sciences, Washington, D.C. Reproduced with permission of Transportation Research Board

Speed differentialWhen a grade is longer than its critical length, it will

cause the speed reduction for heavy vehicle by at least 10 mi/h.

For example, the speed of a truck entering a grade of 5 percent at 55 mi/h will decrease by about 43 mi/h for a grade length of 1,000 ft and to about 27 mi/h for a grade length of 6,000 ft.

Stopping sight distance

What would you guess the perception/reaction time of a typical racer?

1. 0.10s 2. 0.20s 3. 0.30s 4. 0.40s 5. 0.50s

Example ProblemTwo drivers each have a reaction time of 2.5 seconds. One is obeying a 55-mi/h speed limit, and the other is traveling illegally at 70 mi/h. How mush distance will each of the drivers cover while perceiving/reacting to the need to stop, and what will the total stopping distance be for each driver (using practical stopping distance and assuming G=-2.5%)?

Solution

Passing Sight Distance Two-lane highways. The passing vehicle should be able to see sufficient distance

ahead, upcoming traffic to complete the passing maneuver without cutting off the passed vehicle before meeting the opposing vehicles.

Actually, it is harder to passing a long vehicle which exceed 150 feet.

Source: A Policy on Geometric Design of Highway and Streets, AASHTO, 2004

Table PSD values determined by Harwood and Glennon for specific passing scenarios

Source: NCHRP Report 605, Passing Sight Distance Criteria, 2008, Douglas W. Harwood, David K. Gilmore, Karen R. Richard, Joanna M. Dunn, Carlos Sun

Elements of passing sight distance for two-lane highways

Source: A Policy on Geometric Design of Highway and Streets, AASHTO, 2004

Highway Design StandardsDesign Traffic Volume: road should be designed for

an acceptable level of service (LOS) and a specific traffic volume.

LOS A LOS B

LOS C LOS D

LOS E LOS F

Capacity AnalysisBase Conditions for LOSlane widths, lateral clearances, access frequency (non access controlled highways), terrain; traffic stream conditions such as the effects of heavy vehicles (large trucks, buses and RVs), and driver population characteristics.Density: measure of LOS

k=q/uWhere q = flow in veh/h, u = speed in mi/h (km/h) and, k = density in veh/mi (veh/km).

Design SpeedSelected speed used to determine the various design features of the roadway.

Type of Roadway Terrain

Rural Urban

US (mi/h) Metric (km/h) US (mi/h) Metric (km/h)

Freeway

Level 70 110 50 min 80 min

Rolling 70 110 50 min 80 min

Mountainous 50–60 80–100 50 min 80 min

Arterial

Level 60–75 100–120 30–60 50–100

Rolling 50–60 80–100 30–60 50–100

Mountainous 40–50 60–80 30–60 50–100

Collector

Level 40–60 60–100 30+ 50+

Rolling 30–50 50–80 30+ 50+

Mountainous 20–40 30–60 30+ 50+

Local

Level 30–50 50–80 20–30 30–50

Rolling 20–40 30–60 20–30 30–50

Mountainous 20–30 30–50 20–30 30–50

Source: A Policy on Geometric Design of Highways and Streets, AASHTO,2004.

Analysis Flow Rate

Where:vp = 15-min passenger-car equivalent flow rate (pc/h/ln),V = hourly volume (veh/h),PHF = peak-hour factor,N = number of lanes,fHV = heavy-vehicle adjustment factor, andfp = driver population factor.

Peak-Hour Factor

Where:PHF = peak-hour factor,V = hourly volume for hour of analysis,V15= maximum 15-min flow rate within peak hour4 = number of 15-min periods per hour

Heavy Vehicle AdjustmentLarge trucks, buses and recreational vehicles have performance characteristics (slow acceleration and inferior braking) and dimensions (length, height, and width) that have an adverse effect on roadway capacity.The adjustment factor fHV is used to translate the traffic stream from base to prevailing conditions.

Factor Type of Terrain  

  Level Rolling MountainousET (trucks and buses) 1.5 2.5 4.5  

ER (RVs) 1.2 2.0 4.0  

Passenger Car Equivalents (PCEs) for Extended Freeway Segments

ExampleA four-lane urban freeway is located on a rolling terrain. The directional peak-hour volume is 3,800 vehicles with 2% large trucks and 4% buses. No recreational vehicles are present. Calculate fHV.

Solution:

Now assume that a bus strike will eliminate all bus traffic… but it is estimated that for each bus removed from the roadway, six additional cars will be added as travelers seek other means for travel. Calculate fHV.

0.917 = 15.206.0+1

1 =

HVf

Example (cont’d) Number of trucks (before): 76 Number of buses (before): 152 Number of passenger cars (before):

3,572 Number of trucks (after): 76 Number of buses (after): 0 Number of passenger cars (after): 3,572

+152*6=4484 New volume: 4,560 PT=76/4560=0.017 or 1.7%

0.975 = 15.2017.0+1

1 =

HVf

Safety IssuesVehicle Type Total Percent

Passenger Cars 18,350 40.4%

Light Trucks 17,902 39.4%

Large Trucks 3,215 7.1%

Motorcycles 4,595 10.1%

Buses 221 0.5%

Other/Unknown 1,152 2.5%

Total 45,435 100.0%Table Vehicles Involved in Fatal Crashes by Vehicle Type - State : USA, Year : 2009Source: NHTSA-Farshttp://www-fars.nhtsa.dot.gov/Vehicles/VehiclesAllVehicles.aspx

Fatalities by Vehicle TypeYear

Occupants by Vehicle Type

Passenger Cars Light Trucks Large Trucks

2000 20,699 11,526 754

2001 20,320 11,723 708

2002 20,569 12,274 689

2003 19,725 12,546 726

2004 19,192 12,674 766

2005 18,512 13,037 804

2006 17,925 12,761 805

2007 16,614 12,458 805

2008 14,646 10,816 682

2009 13,095 10,287 503Table Persons Killed, by Person Type and Vehicle Type, 2000 - 2009 - State : USASource: Source: NHTSA-Farshttp://www-fars.nhtsa.dot.gov/Trends/TrendsGeneral.aspx

Crash Rates

Year

Vehicle TypePassenger Cars Light Trucks Large Trucks

Involvement Rate per 100 Million VMT

Involvement Rate per 100,000

Registered Vehicles

Involvement Rate per 100 Million VMT

Involvement Rate per 100,000

Registered Vehicles

Involvement Rate per 100 Million VMT

Involvement Rate per 100,000

Registered Vehicles

2000 1.76 21.76 2.17 26.91 2.43 62.262001 1.73 21.41 2.13 26.42 2.31 61.382002 1.7 21.03 2.14 26.49 2.14 57.862003 1.65 20.19 2.14 26.18 2.17 60.862004 1.58 19.27 2.05 25.00 2.22 59.992005 1.56 18.62 2.02 24.19 2.22 58.372006 1.5 17.72 1.93 22.82 2.14 54.042007 1.42 16.57 1.85 21.63 2.04 51.322008 1.3 14.73 1.67 19.01 1.8 45.4

Table Vehicles Involved in Fatal Crashes, 2000 - 2008 - State : USASource: Source: NHTSA-Farshttp://www-fars.nhtsa.dot.gov/Trends/TrendsGeneral.aspx

Rail Transportation for Wind Industry Wind Belt Transportation Improvement Project

(TIGER)Reduce transportation costs by 57 % compared to truck, for every wind turbine shipped by rail;Enable to compete with imported wind, provide long-term U.S. manufacturing jobs and stimulate local economies;Reduce emissions costs by 73% and carbon dioxide emissions by 82 % compared to truck, for every wind turbine shipped by rail;Increase highway safety by 58 % compared to truck, for every wind turbine shipped by rail;Reduce highway maintenance costs by 68 % compared to truck;Nearly double the capacity of a primary rail line that serves the states of Iowa, Missouri, and Minnesota

Source: Wind belt transportation improvement project, TIGER discretionary grant application.

Estimated Per-Mile Transportation and Public Cost Comparison for a Complete Wind Turbine, Rail Compared to Truck

Source: Wind belt transportation improvement project, TIGER discretionary grant application.

The Union Pacific Railroad Spine Line lies in the center of the Midwest Wind Belt, enabling rail transportation of wind turbine components to be economically and efficiently distributed throughout the Wind Belt.Source: Wind belt transportation improvement project, TIGER discretionary grant application.

Short Video about 37 Degree Turning Radius for Blade Truck

http://www.isttrailers.com/blade-trailer.cfm

Other videos:http://www.wcax.com/story/14265930/huge-wind-

turbine-parts-travel-through-vermont?redirected=truehttp://www.youtube.com/watch?NR=1&v=AUCECIl-Z4M http://www.youtube.com/watch?NR=1&v=S1uEAv-8Iqc http://www.youtube.com/watch?NR=1&v=JZ4xX3OiGbY

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