Presenter Information

Mir Atiqullah
Emmanuel Nnamani

Start Date

6-6-2017 12:00 AM

Description

Short Abstract:

Aerodynamic drag of tractor-trailers using add-on devices were studied using CFD simulations and wind tunnel testing on scale-model. Five external attachments were tested for effectiveness: (i) front fairing, (ii) trailer top, (iii) side skirt, (iv) gap cover and (v) trailing end oval. The resulting aerodynamic drag coefficients were significantly lower.

Full Abstract:

Aerodynamic drag has significant influence on fuel consumption in large tractor-trailers. The primary objective of the current study is to reduce aerodynamic drag using add-on devices. Two approaches have been employed to measure the effectiveness of these devices: CFD simulation and scale model testing in wind tunnel. A 3D full-scale model was developed in SOLIDWORKS package. In addition, a scale model prototype was constructed to perform wind tunnel tests. Five external attachments were tested for effectiveness: (i) front fairing, (ii) trailer top, (iii) side skirt, (iv) gap cover and (v) rear end oval. The drag reducing effects of the attachments were measured at various air speeds using both CFD and wind-tunnel simulations. The drag reducing effects of the various add-on devices and agreements between the results from CFD and wind tunnel testing were recorded. The resulting drag coefficients (C¬d) were significantly lower than those without add-ons. The wind tunnel model was limited to 15 inches in length, compared to over 70 feet for a real tractor-trailer. Tests were also conducted for various yaw angles for their effects on drag. This study demonstrated the importance of optimizing a tractor-trailer shape by streamlining the airflow around and over the tractor-trailer assembly.

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Jun 6th, 12:00 AM

Aerodynamic Drag Reduction of Class 8 Tractor-Trailers using External Attachments

Short Abstract:

Aerodynamic drag of tractor-trailers using add-on devices were studied using CFD simulations and wind tunnel testing on scale-model. Five external attachments were tested for effectiveness: (i) front fairing, (ii) trailer top, (iii) side skirt, (iv) gap cover and (v) trailing end oval. The resulting aerodynamic drag coefficients were significantly lower.

Full Abstract:

Aerodynamic drag has significant influence on fuel consumption in large tractor-trailers. The primary objective of the current study is to reduce aerodynamic drag using add-on devices. Two approaches have been employed to measure the effectiveness of these devices: CFD simulation and scale model testing in wind tunnel. A 3D full-scale model was developed in SOLIDWORKS package. In addition, a scale model prototype was constructed to perform wind tunnel tests. Five external attachments were tested for effectiveness: (i) front fairing, (ii) trailer top, (iii) side skirt, (iv) gap cover and (v) rear end oval. The drag reducing effects of the attachments were measured at various air speeds using both CFD and wind-tunnel simulations. The drag reducing effects of the various add-on devices and agreements between the results from CFD and wind tunnel testing were recorded. The resulting drag coefficients (C¬d) were significantly lower than those without add-ons. The wind tunnel model was limited to 15 inches in length, compared to over 70 feet for a real tractor-trailer. Tests were also conducted for various yaw angles for their effects on drag. This study demonstrated the importance of optimizing a tractor-trailer shape by streamlining the airflow around and over the tractor-trailer assembly.