Optimizing Truck Fleet Aerodynamics for Green Logistics Ltd.

Thesis Abstract

This study addresses the escalating fuel consumption and greenhouse gas emissions associated with long-haul trucking by examining aerodynamic optimization strategies for a commercial fleet operated by Green Logistics Ltd., a mid-size logistics provider serving regional and national routes. Despite advances in vehicle design, real-world aerodynamic gains are often underexploited due to operational constraints, vehicle heterogeneity, and disparate route profiles. The aim is to quantify, model, and validate aerodynamic interventions that produce measurable reductions in drag, fuel use, and emissions without compromising payload capacity or schedule integrity. Specific objectives are to (i) identify aerodynamics features with the greatest potential for drag reduction across the fleet, (ii) develop a decision-support framework linking retrofitting options, route characteristics, and load profiles, (iii) quantify fuel and emission savings from implemented modifications under representative operating conditions, and (iv) evaluate the cost-benefit profile and payback periods for different intervention packages. The study adopts a mixed-methods design anchored in both empirical testing and operational data analytics. The population comprises 250 turnkey-trailer configurations and 60 tractor-trailer combinations in Green Logistics Ltd.’s fleet, with a purposive sample of 40 tractors and 120 trailers selected to reflect variability in model year, aerodynamic add-ons, and typical route profiles. Data collection combines controlled wind-tunnel or CFD-derived aerodynamic drag coefficients for representative tractor-trailer configurations, onboard telematics and fuel consumption records over a 12-month rolling window, and on-road performance data (speed, elevation, cargo weight, and braking events) from 2000 trips. Instruments include high-fidelity CFD simulations, a standardized aerodynamic retrofit checklist, fuel flow meters, telematics data loggers, and maintenance records. Validity and reliability are ensured through triangulation across CFD results, dynamometer measurements, and real-world fuel data, with instrument calibration aligned to ISO 17025 guidelines for measurement accuracy. Ethical considerations address fleet data privacy and proprietary design information, with institutional approvals and non-disclosure agreements in place. The analysis integrates computational fluid dynamics outputs with empirical fuel data within a multi-stage modeling framework. At the configuration level, regression analysis (weighted least squares) quantifies the relationship between aerodynamic features (underbody streamlining, gap sealants, trailer side skirts, roof deflectors) and drag coefficient reductions, controlling for vehicle mass and speed. At the fleet level, a mixed-effects model assesses how retrofits influence fuel economy across routes with differing grade profiles and traffic conditions. A cost-benefit model, incorporating net present value (NPV) and payback period calculations, evaluates retrofit packages under various fuel price scenarios. The theoretical foundation draws on the Theory of Planned Behavior to examine operator acceptance of aerodynamic modifications and the Aerodynamic Drag Reduction framework to interpret the measured drag reductions, supplemented by the Diffusion of Innovation theory to anticipate adoption patterns within fleet operations. A meta-analysis of prior empirical studies accompanies the empirical work, culminating in a conceptual model that links retrofit decisions to fuel savings, emissions reductions, and operational feasibility. Expected findings indicate that trailer undercarriage and side-skirt enhancements yield the most consistent drag reductions across vehicle variants, with an average drag coefficient decrease of 7.5% (range 4–12%) and corresponding fuel economy improvements of 6–9% under typical long-haul conditions. Roof deflectors show moderate gains in hilly terrains, while aerodynamic gap seals contribute marginal benefits in well-maintained road networks. The cost-benefit analysis is projected to demonstrate favorable payback periods (2–4 years) for modular retrofit kits, with higher returns on routes exhibiting persistent high-speed cruising and frequent headwinds. The study contributes to knowledge by delivering a data-driven, fleet-wide optimization framework for aerodynamic interventions in a real-world logistics setting, bridging the gap between laboratory aero-design results and daily operations. It provides a validated methodology for assessing aerodynamic retrofits, a decision-support tool for fleet managers, and a policy-relevant model for translating drag reductions into measurable environmental and economic gains. The conclusion emphasizes that targeted, modular aerodynamic enhancements can yield substantial fleet-wide fuel savings and emission reductions without compromising service levels. Recommendations include prioritizing side-skirt and undercarriage upgrades for immediate implementation, developing operator training to improve acceptance and consistent use of retrofits, and establishing continuous monitoring protocols to recalibrate models with evolving vehicle technologies and route patterns.