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

2. What is going to happen if you followed a truck moving a wind turbine component up to a hill?
How long will it take you to pass a truck carrying a wind turbine blade?

3. Vehicle Performance Why vehicle performance important?
Determines all highway design and traffic operations
Defines how transportation engineers must react to advancing vehicle technologies
The single most important factor in defining the tradeoff between mobility (speed) and safety

5. Forces acting on a road vehicle

8. Power required to overcome air resistance

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

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

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

12. Tire deformation (90%) Pavement penetration (4%)
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).

15. Example Problem

16. Solution

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

18. Speed differential
When 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.

19. Stopping sight distance

20. 1. Source: Highway Engineering, Paul H. Wright/ Karen K. Dixon, 2004

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

22. Example Problem
Two 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%)?

23. Solution

24. 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

25. 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

26. Elements of passing sight distance for two-lane highways Source: A Policy on Geometric Design of Highway and Streets, AASHTO, 2004

27. Highway Design Standards
Design Traffic Volume: road should be designed for an acceptable level of service (LOS) and a specific traffic volume.
LOS A LOS B
Source: A Policy on Geometric Design of Highway and Streets, AASHTO, 2004

28. LOS C LOS D
LOS E LOS F

29. Capacity Analysis Base Conditions for LOS lane 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/u
Where q = flow in veh/h, u = speed in mi/h (km/h) and, k = density in veh/mi (veh/km).

30. Design Speed
Selected speed used to determine the various design features of the roadway.
Type of Roadway
Terrain
Rural
Urban
US (mi/h)
Metric (km/h)
Freeway
Level 70
110
50 min
80 min
Rolling
Mountainous
50–60
80–100
Arterial
60–75
100–120
30–60
50–100
40–50
60–80
Collector
40–60
60–100
30+
50+
30–50
50–80
20–40
Local
20–30
Source: A Policy on Geometric Design of Highways and Streets, AASHTO,2004.

31. 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, and
fp = driver population factor.

32. Peak-Hour Factor Where: PHF = peak-hour factor,
V = hourly volume for hour of analysis,
V15= maximum 15-min flow rate within peak hour
4 = number of 15-min periods per hour

33. Passenger Car Equivalents (PCEs) for Extended Freeway Segments
Heavy Vehicle Adjustment Large 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.
Passenger Car Equivalents (PCEs) for Extended Freeway Segments
Factor
Type of Terrain
Level
Rolling
Mountainous
ET (trucks and buses)
1.5
2.5
4.5
ER (RVs)
1.2
2.0
4.0

35. Example
A 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.

36. 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, *6=4484
New volume: 4,560
PT=76/4560=0.017 or 1.7%

37. Safety Issues Vehicle 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%
45,435
100.0%
Table Vehicles Involved in Fatal Crashes by Vehicle Type - State : USA, Year : 2009
Source: NHTSA-Fars

38. Fatalities by Vehicle Type
Year
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
2008
14,646
10,816
682
2009
13,095
10,287
503
Table Persons Killed, by Person Type and Vehicle Type, State : USA
Source: Source: NHTSA-Fars

39. Crash Rates
Year
Vehicle Type
Passenger Cars
Light Trucks
Large Trucks
Involvement Rate per 100 Million VMT
Involvement Rate per 100,000 Registered Vehicles
2000
1.76
21.76
2.17
26.91
2.43
62.26
2001
1.73
21.41
2.13
26.42
2.31
61.38
2002
1.7
21.03
2.14
26.49
57.86
2003
1.65
20.19
26.18
60.86
2004
1.58
19.27
2.05
25.00
2.22
59.99
2005
1.56
18.62
2.02
24.19
58.37
2006
1.5
17.72
1.93
22.82
54.04
2007
1.42
16.57
1.85
21.63
2.04
51.32
2008
1.3
14.73
1.67
19.01
1.8
45.4
Table Vehicles Involved in Fatal Crashes, State : USA
Source: Source: NHTSA-Fars

40. 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.

41. 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.

42. 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.

43. Short Video about 37 Degree Turning Radius for Blade Truck
Other videos: