Exhaust Braking System Temperature Control for After-Treatment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The risk of the after-treatment system temperature falling to undesirable low levels during vehicle operation, particularly on downhill slopes, which can lead to reduced exhaust purification efficiency and potential poisoning of catalysts due to sulfur reactions, resulting in suboptimal or no exhaust treatment until the system is reheated.
Innovation Solution
Prioritizing the activation of the exhaust braking system over other auxiliary braking systems to utilize the heating effect and maintain a desired temperature in the after-treatment system, ensuring continued efficient exhaust treatment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If the vehicle uses auxiliary braking systems on downhill slopes, then the braking performance is improved, but the after-treatment system temperature falls to undesirable low levels
Solution Approach 1:
The patent converts the harmful cooling effect of exhaust braking into a beneficial heating effect for the after-treatment system. By prioritizing exhaust braking over other auxiliary braking systems, the exhaust stream's thermal energy is preserved to maintain catalyst temperature, transforming what would be a harmful temperature drop into a useful heating mechanism for exhaust treatment.
Solution Approach 2:
The exhaust braking system serves dual purposes: providing braking force for the vehicle and simultaneously heating the after-treatment system through the exothermic oxidation of soot particles in the exhaust stream. The system uses its own exhaust stream as both the braking medium and the heat source, eliminating the need for separate heating mechanisms.
2Use of energy by moving object
If the after-treatment system temperature is low, then fuel consumption is reduced, but exhaust purification efficiency decreases and catalysts may be poisoned by sulfur
Solution Approach 1:
The control system continuously monitors the temperature in the after-treatment system and adjusts braking system selection based on temperature feedback. When temperature drops below optimal levels, the system prioritizes exhaust braking to restore temperature, creating a closed-loop control mechanism that maintains purification efficiency while managing fuel consumption.
Solution Approach 2:
The system dynamically changes the operational parameters of the braking systems based on after-treatment temperature conditions. By switching between exhaust braking and other auxiliary braking systems according to temperature thresholds, the system optimizes both fuel consumption and exhaust purification efficiency under varying operating conditions.
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
This approach effectively maintains the after-treatment system temperature, preventing reduced exhaust purification and potential catalyst poisoning, ensuring consistent and optimal exhaust treatment performance even in situations where cooling occurs, such as on downhill slopes.
Implementation Method 1
Prioritizing the activation of the exhaust braking system over other auxiliary braking systems to utilize the heating effect and maintain a desired temperature in the after-treatment system
Implementation Method 2
The function in connection with treatment of exhaust streams is often controlled by chemical reactions
Implementation Method 3
a so-called catalytic purification process may be used, so that after-treatment systems in e.g. vehicles and other vessels usually comprise one or more catalysts
Implementation Method 4
the exhaust stream is led e.g. through a filter structure where soot particles are caught from the exhaust stream passing through, for storage in the particulate filter
Implementation Method 5
sulphur which is normally contained in fuel such as e.g. diesel may react chemically with the active coating, often consisting of precious metals or other metals, which components in the after-treatment system usually comprise, so that the metal coating may become at least temporarily poisoned
Data Source
Figure 1A
Figure 1B
Figure 2
AI summary
The present invention pertains to a method when driving a vehicle (100), wherein said vehicle (100) comprises a combustion engine (101) and an exhaust system with an after-treatment system (200), for after-treatment of an exhaust stream resulting from said combustion engine (101), wherein said vehicle (100) also comprises an exhaust braking system (215) and at least one auxiliary braking system (117) separate from the first exhaust braking system. The method comprises: on request for activation of said first auxiliary braking system (117), at least to activate said exhaust braking system (215). The invention also relates to a system and a vehicle.