Turbocharger Turbine Counter Torque for Catalyst Warm-Up
Solution Overview
Problem
Turbocharged internal combustion engines require a longer warm-up time for exhaust purification catalysts due to heat energy recovery by the turbocharger, and existing methods to reduce this time are either inefficient or complex.
Innovation Solution
Applying counter torque to the turbine of the turbocharger to recirculate exhaust gas back to the compressor, thereby increasing the temperature of the exhaust gas and reducing warm-up time through a simple control procedure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the catalytic converter is arranged downstream of the turbocharger to increase engine output, then the engine output is improved, but the warm-up time of the exhaust purification catalyst increases due to heat energy recovery by the turbocharger
Solution Approach 1:
The control means determines whether warm-up is needed in advance and, if so, applies counter torque to the turbine before normal operation begins. This preliminary action prevents heat loss during the critical warm-up period by restraining turbine rotation that would otherwise consume exhaust heat energy, thereby reducing warm-up time while maintaining the downstream catalytic converter arrangement for engine output improvement
2Loss of energy
If the pressure difference between turbine inflow and outflow exhaust pressures is controlled to reduce turbine resistance, then the consumption of exhaust heat energy by the turbine is reduced, but a complicated control process is required to maintain the pressure difference within a predetermined range
Solution Approach 1:
Instead of controlling pressure differences through complex multi-parameter regulation, the invention changes the approach by directly applying counter torque to the turbine. This single parameter control (torque application) achieves the same energy conservation goal while dramatically simplifying the control process, eliminating the need for complex pressure differential management
3Productivity
If the turbine rotation is restrained to reduce exhaust heat energy consumption, then the warm-up efficiency is improved, but the engine output may be affected due to the turbocharger's energy recovery function
Solution Approach 1:
The control means dynamically adjusts turbine rotation based on operational conditions. During warm-up, counter torque is applied to restrain rotation and improve warm-up efficiency. During normal operation, the turbine rotates freely to maintain engine output. This dynamic switching resolves the contradiction by optimizing performance for each operational phase
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 method effectively shortens the warm-up time of the exhaust purification catalyst by maintaining high exhaust gas temperature in the exhaust passage, allowing for quicker activation of the catalyst without the need for complex pressure control.
Implementation Method 1
The turbocharger is a device whereby the energy of the exhaust gas is recovered with the use of a turbine to drive a compressor
Data Source
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AI summary
A warm-up system for warming up an exhaust purification catalyst (4) arranged in an exhaust passage (3) of an engine (2) equipped with a turbocharger (1). The warm-up system includes an electric motor (1m) coupled to a turbine (1t) of the turbocharger (1), and control means (5) for operating the electric motor (1m) to apply counter torque to the turbine (1t) when the exhaust purification catalyst (4) needs to be warmed up.