Reducing Agent Content Evaluation via Thermal Change Rate
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for evaluating the effective component content of reducing agents in SCR systems are inadequate, leading to potential misprovision of undesired liquids or concentrations, which can result in inadequate emission control and engine performance issues.
Innovation Solution
A method and system that utilize a heat transfer provision arrangement to determine the effective component content of reducing agents by measuring the mean temperature change rate, prevailing volume, and surrounding temperatures, allowing for accurate and robust evaluation of the reducing agent's quality, including differentiation between intended and unintended liquids.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If resistance-based methods are used to estimate urea concentration, then the measurement can be performed with simple sensors, but the measurement precision is insufficient to reliably differentiate between intended and unintended liquids
Solution Approach 1:
The patent replaces electrical resistance-based sensing with thermal field-based sensing. Instead of using electrical properties to detect urea concentration, the system uses thermal conductivity and heat transfer characteristics of the liquid, which provide more precise differentiation between liquid types and concentrations.
Solution Approach 2:
The patent changes the detection parameter from electrical resistance to thermal properties (thermal conductivity, heat capacity, temperature change rate). This parameter change enables more accurate concentration measurement because thermal properties vary more distinctly between different liquids and urea concentrations compared to resistance.
2Measurement precision
If thermal conductivity-based methods are used to estimate urea concentration, then improved measurement capability is achieved, but the system requires additional temperature sensors and control mechanisms
Solution Approach 1:
The patent makes the heating element serve multiple functions: it acts as both a heating source for thermal conductivity measurement and as a temperature sensor through self-temperature measurement capability. This eliminates the need for separate heating elements and temperature sensors, reducing system complexity while maintaining measurement precision.
Solution Approach 2:
The heating element performs self-temperature measurement, meaning it determines its own temperature without requiring external sensors. This self-service capability reduces the number of components needed and simplifies the overall system architecture while maintaining accurate thermal-based concentration measurement.
3Measurement precision
If multiple temperature measurements are performed to determine concentration accurately, then measurement precision improves, but the evaluation time increases
Solution Approach 1:
The patent uses periodic heating with specific duty cycles to transfer thermal energy to the liquid in controlled intervals. By applying heat periodically rather than continuously, the system achieves sufficient temperature change for measurement while reducing total energy input and measurement time, balancing precision with speed.
Solution Approach 2:
The system performs preliminary temperature equalization by allowing the heating element and liquid to reach thermal equilibrium before the actual measurement begins. This preliminary action ensures accurate baseline temperature readings without requiring extended measurement periods during the actual concentration evaluation.
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 provides a reliable, efficient, and cost-effective means to assess the effective component content of reducing agents, ensuring appropriate emission control and engine performance by accurately identifying any deviations in concentration or liquid type, thereby preventing inappropriate reducing agent supply.
Implementation Method 1
determining a mean temperature change rate for the reducing agent; determining the effective component content of the reducing agent on the basis of the mean temperature change rate
Implementation Method 2
in which a heat transfer provision arrangement is provided
Data Source
Figure 1~2a
Figure 2b
Figure 2c
AI summary
The invention relates to a method for evaluating an effective component content (C) of a reducing agent for engine exhaust gas processing arranged in a container (205) in which a heat transfer provision arrangement (240) is provided, comprising the steps of: - determining (s410; s420) a prevailing volume (V) and temperature (T1) of said reducing agent in said container (205); - determining (s430) a prevailing temperature (T2) of said heat transfer provision arrangement (240); - determining (s440) a prevailing temperature (T3) of a medium surrounding said container (205); - for a predetermined time period, determining (s450) a mean temperature change rate (Tprim) for said reducing agent; and - determining (s460) said effective component content (C) of said reducing agent on the basis of the above determined parameters.