Urea Injection Plate Structure for Exhaust Gas Decomposition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing exhaust gas treatment systems require complex structures for urea water evaporation and often result in incomplete mixing of urea water with exhaust gas, leading to inefficient decomposition and potential clogging.
Innovation Solution
Incorporation of an inclined plate with a convex portion for urea water adhesion and a concave portion for exhaust gas flow in the exhaust passage, promoting efficient evaporative decomposition of urea water into ammonia.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a heater is used to evaporate and decompose urea water, then decomposition efficiency is improved, but device complexity increases due to electrical current requirements
Solution Approach 1:
The exhaust gas itself serves as the heating source to evaporate and decompose urea water, eliminating the need for external heaters and electrical current. The high-temperature exhaust gas directly contacts the urea water on the inclined plate, enabling self-heating and decomposition without additional energy input devices
Solution Approach 2:
The heating function is extracted from the exhaust gas and directly applied to the urea water contact surface. The exhaust gas flow path is designed to maximize heat transfer to the inclined plate where urea water adheres, separating the heating function from complex electrical heater systems
2Productivity
If urea water is injected into the exhaust passage, then ammonia generation is enabled, but mixing with exhaust gas causes difficulty in contacting the impingement surface
Solution Approach 1:
The inclined plate features a convex curved surface that promotes urea water adhesion and prevents immediate mixing with exhaust gas. The curved geometry allows urea water to spread and maintain contact with the heating surface while the exhaust gas flows over it, ensuring effective heat transfer and decomposition
Solution Approach 2:
The inclined plate is positioned at an angle relative to the exhaust gas flow direction, creating a three-dimensional configuration where urea water adheres to the slanted surface. This angular arrangement allows simultaneous contact between urea water, heated surface, and exhaust gas flow without complete mixing
3Stability of the object's composition
If urea water mixes with exhaust gas before reaching the impingement body, then homogeneity is improved, but contact with the decomposition surface is reduced
Solution Approach 1:
Urea water is injected and adheres to the inclined plate before significant mixing with exhaust gas occurs. This preliminary positioning on the heated surface ensures that decomposition begins immediately upon contact, maintaining both adequate mixing over time and effective surface contact for efficient ammonia generation
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
Enhances urea water decomposition with a simple structure, preventing clogging and ensuring effective ammonia generation for NOx reduction in the exhaust gas.
Implementation Method 1
promoting efficient evaporative decomposition of urea water into ammonia
Implementation Method 2
exhaust gas flows; an injection unit that injects urea water into the exhaust passage
Data Source
AI summary
An exhaust gas treatment equipment includes an exhaust passage through which exhaust gas flows, an injection unit that injects urea water into the exhaust passage, an inclined plate that is disposed within the exhaust passage and is inclined with respect to a virtual plane orthogonal to an injection direction in which the injection unit injects urea water, and an opposing plate provided downstream of the inclined plate in the exhaust passage so as to face the inclined plate and, together with the inclined plate, forms an injection space into which the urea water is injected. The inclined plate includes a convex portion that is formed on a facing surface that faces the injection unit and onto which the urea water is injected, and a concave portion that is formed on a back surface opposite to the facing surface and serves as a flow path for the exhaust gas.