Roof-mounted Roller Belt Drag Reduction Apparatus
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Transportation vehicles face significant fuel consumption due to viscous drag forces generated by air resistance, which is particularly challenging for vehicles with large contact areas like trucks and trains, where shape modifications are not feasible, leading to inefficient fuel use and increased pollution.
Innovation Solution
A viscous drag reduction apparatus comprising a pair of rollers connected to a vehicle's roof, a frictional belt wrapped around the rollers, and a motor system controlled by a drag controller that adjusts belt speed based on wind and vehicle speed to optimize drag reduction, allowing the apparatus to harness and convert drag forces into energy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If the shape of the vehicle is modified to be more streamline, then viscous drag resistance is reduced, but the vehicle shape cannot be modified for vehicles with large contact area such as trucks and trains
Solution Approach 1:
The invention divides the vehicle surface into multiple segments with multiple belts arranged in rows and columns. Each belt segment independently interacts with the airflow, allowing the system to be applied to large surface areas of trucks and trains without requiring overall shape modification. This segmentation enables drag reduction on vehicles where complete shape redesign is not feasible.
Solution Approach 2:
The invention introduces belts as intermediary elements between the airflow and the vehicle surface. These belts act as mediators that interact with the boundary layer airflow, generating vortices that reduce viscous drag. This intermediary approach allows drag reduction without modifying the fundamental shape of the vehicle, making it applicable to trucks and trains with fixed large-contact-area designs.
2Force
If a belt system is installed on the vehicle roof, then viscous drag is reduced, but the apparatus complexity increases
Solution Approach 1:
The belt system is designed to be self-driven by the airflow itself. The relative motion between the airflow and the belts automatically generates the driving force, eliminating the need for external motors or power sources. This self-service mechanism significantly reduces apparatus complexity while maintaining effective drag reduction functionality.
Solution Approach 2:
The belts are designed with variable speeds that can be adjusted based on operating conditions. The system transitions from a static configuration to a dynamic one where belt speeds can be optimized for different vehicle speeds and airflow conditions, improving performance without requiring overly complex control mechanisms.
3Use of energy by moving object
If the belt speed is increased to reduce drag, then fuel efficiency improves, but energy consumption by the motor increases
Solution Approach 1:
The invention converts the harmful viscous drag force into a beneficial driving force for the belts. The airflow that would normally create drag instead drives the belts to rotate, generating vortices that further reduce drag. This converts what was previously a pure energy loss into a useful effect, improving fuel efficiency without requiring additional motor energy input.
Solution Approach 2:
The system employs periodic vortex generation through the rotating belts, creating oscillating flow patterns that enhance mixing and reduce boundary layer thickness. This periodic action is more energy-efficient than continuous high-speed rotation, as it leverages the unsteady nature of the flow to achieve drag reduction with lower average belt speeds.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The apparatus effectively reduces viscous drag resistance by up to 50%, leading to improved fuel efficiency and reduced air pollution, with the potential to convert drag energy into electric energy for vehicle use.
Implementation Method 1
a belt having a frictional surface and partially wrapped around the pair of rollers, such that the pair of rollers allow the belt to rotate in response to an air flow generated around the vehicle when the vehicle is in motion
Implementation Method 2
a reverse flow cover connected to the front end of the roof of the vehicle and extending to a top of the belt so as to block an air back flow generated by the belt when rotating
Data Source
AI summary
Described herein are a viscous drag reduction apparatus and a method. The apparatus includes a pair of rollers connected to a supporting surface on a roof of the vehicle, a belt having a frictional surface and partially wrapped around the pair of rollers, such that the pair of rollers allow the belt to rotate in response to an air flow generated around the vehicle when the vehicle is in motion, the pair of rollers having a length in an axial direction that is at least as long as a width of the belt, an assembly of the pair of rollers and the belt being at least partially recessed with respect to a top line of the roof, and a reverse flow cover connected to the front end of the roof of the vehicle to block an air back flow generated by the belt when rotating.