Soot Load Estimation Using Pressure Drop Segmentation

The patent transforms the pressure drop measurement approach by introducing dimensionless parameters (Euler number, Reynolds number) and applying mathematical transformations to the governing equations. This allows the system to maintain closed-loop feedback while significantly improving soot load prediction accuracy across varying operating conditions by making the solution independent of specific flow and temperature conditions.

The patent introduces intermediate computational steps including calculating dimensionless numbers (Euler, Reynolds), determining pressure drop coefficients, and applying mathematical transformations as intermediaries between the raw pressure drop measurement and the final soot load estimation. These intermediaries enable more accurate predictions by accounting for complex flow dynamics without requiring additional physical sensors.

The patent changes the approach from using empirical correlations directly to using dimensionless parameters (Euler number Eu = 2ΔP/ρu² and Reynolds number Re = ρuD/μ) that capture the essential physics across different conditions. By expressing pressure drop in terms of these dimensionless groups and solving the governing equations analytically, the method achieves both broad applicability and high accuracy under dynamic conditions.

The patent replaces empirical mechanical correlations with an analytical solution based on fundamental fluid mechanics principles. By deriving the soot load from first principles using the Euler and Reynolds numbers, the system achieves universal applicability across different temperatures, flow rates, and filter geometries without relying on condition-specific empirical data.

The patent segments the total pressure drop into distinct components: inlet/outlet contraction losses, inlet/outlet channel losses, and permeable layer losses. By dividing the pressure drop analysis into these segments and applying appropriate loss coefficients to each, the method accurately accounts for all major pressure drop contributions while maintaining a systematic and manageable analytical framework.

The patent introduces pressure drop coefficients (K values) for different loss mechanisms as intermediaries that quantify the contribution of each segment (inlet, outlet, channels, permeable layers) to the total pressure drop. These coefficients serve as mediators that translate geometric and flow parameters into accurate pressure drop predictions for each segment, enabling comprehensive accounting without excessive complexity.

The patent implements a closed-loop feedback system that continuously monitors pressure drop and calculates real-time soot load estimates. This feedback enables the control system to determine the optimal regeneration timing based on actual filter conditions, triggering regeneration only when soot load reaches thresholds that balance filter protection with energy efficiency, thereby avoiding both over-regeneration and under-regeneration.

The patent employs dynamic soot load estimation that adapts to changing operating conditions (flow rate, temperature, pressure) in real-time. By continuously updating the soot load calculation based on current operating parameters and historical data, the system dynamically adjusts regeneration timing to optimize the balance between filter protection and energy consumption, rather than using fixed schedules.

The continuous feedback mechanism monitors actual soot accumulation and compares it against failure thresholds, enabling the system to schedule regeneration at the precise moment when it becomes necessary for filter protection. This ensures regeneration is performed infrequently enough to minimize energy consumption but frequently enough to prevent filter failure, optimizing the trade-off between these two objectives.

The system performs preliminary soot load estimation and trend analysis to predict when regeneration will be needed, allowing proactive scheduling before critical loading occurs. This preliminary action enables optimization of regeneration timing to minimize energy consumption while ensuring filter durability, rather than reacting only after threshold exceedance.