Exhaust Gas Manifold Layout for Compact Heated Catalyst Flow
Solution Overview
Problem
Existing exhaust gas processing devices face challenges in reducing size while maintaining efficient gas flow and preventing interference between components such as diffusion tubes and electrically heated catalysts.
Innovation Solution
The device incorporates a manifold that changes the direction of exhaust gas flow, a heater positioned upstream to heat the gas, and a case design with an inlet-side cut-out to allow unobstructed gas passage, along with a double tube structure to prevent heat loss and optimize catalyst activation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the diffusion tube is inserted deeper into the inner tube, then the size reduction is achieved, but the diffusion tube interferes with the electrically heated catalyst
Solution Approach 1:
The patent extracts the diffusion tube from the conventional inner tube structure and repositions it as an outer tube surrounding the heater assembly. This extraction allows the diffusion tube to be separated from the heater, eliminating interference while maintaining compact size through the nested configuration of the outer tube around the heater and catalyst carrier.
Solution Approach 2:
The patent changes the spatial arrangement from a linear insertion (diffusion tube inside inner tube) to a radial configuration (diffusion tube as outer tube surrounding heater). This dimensional change allows both components to coexist without interference while achieving size reduction through the compact nested structure.
2Volume of moving object
If the size of exhaust gas processing device is reduced, then compactness is achieved, but flow of exhaust gas is inhibited
Solution Approach 1:
The patent segments the exhaust gas flow path into distinct regions: an inlet passage for exhaust gas entry, a reaction chamber containing the heater and catalyst carrier, and an outlet passage for processed gas. This segmentation allows efficient flow through compact spaces by directing gas flow along defined pathways rather than requiring large open spaces.
Solution Approach 2:
The patent employs a nested structure where the heater is positioned within the reaction chamber, which is surrounded by the diffusion tube (outer tube). This nested arrangement maximizes space utilization while maintaining adequate flow passages, achieving both compact size and efficient exhaust gas flow.
3Loss of time
If heater is positioned upstream of catalyst carrier, then catalyst activation is improved, but heat loss increases
Solution Approach 1:
The patent introduces the reaction chamber as an intermediary structure between the heater and the surrounding environment. The reaction chamber acts as a thermal insulator that directs heat from the heater to the catalyst carrier while minimizing heat loss to the external environment, thus improving catalyst activation efficiency.
Solution Approach 2:
The patent utilizes the thin-walled reaction chamber structure as a thermal barrier. The chamber walls provide thermal insulation that retains heat within the reaction zone, preventing excessive heat loss while still allowing the heater to effectively activate the catalyst carrier positioned within the same chamber.
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 configuration achieves a compact size without inhibiting gas flow, ensures rapid catalyst activation, and maintains efficient purification capabilities by minimizing interference and overheating risks.
Implementation Method 1
a heater provided on upstream of the first catalyst carrier in a flowing direction of the exhaust gas, the heater being configured to heat the exhaust gas that has entered from the manifold and that is to be guided to the first catalyst carrier
Implementation Method 2
a first catalyst carrier into which the exhaust gas that has been guided from the outlet of the manifold flows, the first catalyst carrier being configured to purify the exhaust gas that is flowing in the second direction
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An exhaust gas processing device (1) is provided with: a manifold (10) configured to change a travelling direction of exhaust gas (G) from a first direction (P) to a second direction (Q); a first catalyst carrier (25) into which the exhaust gas (G) that has been guided from the manifold (10) flows, the first catalyst carrier (25) being configured to purify the exhaust gas (G) that is flowing in the second direction (Q); a heater (22) provided on the upstream of the first catalyst carrier (25) in the flowing direction of the exhaust gas (G), the heater (22) being configured to heat the exhaust gas (G) that has entered from the manifold (10); and a case (20) accommodating the first catalyst carrier (25) and the heater (22), wherein an inlet-side opening portion (20a) of the case (20) is inserted into the manifold (10) to a position facing an inlet (10a) of the manifold (10), and the inlet-side opening portion (20a) is formed with an inlet-side cut-out portion (20c) configured to allow passage of the exhaust gas (G).