LPG Injection Control for Diesel Engine Efficiency

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Solution Overview

Problem

Existing diesel fuel engine systems that inject combustible gases, such as LPG, face inefficiencies due to factors like air filter deterioration, which can reduce the effectiveness of gas injection and lead to lower engine performance compared to diesel fuel combustion alone.

Innovation Solution

A method and system that inject LPG gas into the air intake stream of diesel engines, adjusting the injection rate based on engine parameters like RPM and load, maintaining an optimal LPG concentration of 0.2% to 0.6% by volume, using sensors and a microprocessor to calculate and adjust gas injection rates for improved combustion efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a fixed gas injection rate is used, then the system is simple to operate, but the engine efficiency deteriorates under varying load conditions

Engineering Contradiction:
Improvegas injection controlVSAvoidengine efficiency
Core Design Contradiction:
Ease of operationVSProductivity

Solution Approach 1:

The patent applies dynamics by transitioning from a fixed gas injection rate to a variable injection rate that dynamically adapts to changing engine load conditions. The control system continuously adjusts the gas injection rate based on real-time engine parameters (load, speed, temperature), allowing the system to optimize combustion efficiency across different operating conditions while maintaining ease of operation through automated control.

Inventive Principle:
Principle #15Dynamics

2Power

If the gas injection rate is increased to meet higher load requirements, then the power output improves, but the combustion efficiency decreases due to improper mixing

Engineering Contradiction:
Improvepower outputVSAvoidcombustion efficiency
Core Design Contradiction:
PowerVSLoss of energy

Solution Approach 1:

The patent implements feedback control by continuously monitoring engine parameters (load, speed, temperature) and using this information to adjust the gas injection rate. The control system receives real-time data from sensors, processes this information, and modifies the injection rate accordingly to maintain optimal combustion conditions. This closed-loop feedback mechanism ensures that power output is maximized while combustion efficiency is preserved across varying load conditions.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent applies parameter changes by dynamically adjusting multiple engine parameters including gas injection rate, air-fuel ratio, and ignition timing based on operating conditions. The control system modifies these parameters in coordination to optimize combustion efficiency at different load levels, preventing energy loss from improper mixing while maintaining adequate power output.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If air filter deterioration reduces air intake flow, then the engine protection function is activated, but the gas injection effectiveness is not proportionally decreased

Engineering Contradiction:
Improveengine protectionVSAvoidgas injection effectiveness
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent uses feedback control to compensate for air filter deterioration by continuously monitoring engine parameters and adjusting the gas injection rate accordingly. When air intake flow is restricted, the control system detects the change in engine operating conditions and proportionally adjusts the gas injection rate to maintain optimal combustion effectiveness, preventing the harmful effects of improper mixing while preserving engine protection functions.

Inventive Principle:
Principle #23Feedback

4Device complexity

If a simple solenoid valve is used for gas injection, then the device complexity is low, but the gas injection flow rate cannot be precisely controlled

Engineering Contradiction:
Improveinjection control systemVSAvoidgas injection flow rate control
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent replaces simple mechanical control (solenoid valve) with an electronic control system that uses sensors, microprocessors, and advanced valve mechanisms. This substitution enables precise control of gas injection flow rate through electronic regulation, allowing accurate measurement and adjustment of injection parameters while maintaining acceptable device complexity through integrated electronic control.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

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 enhances diesel fuel combustion efficiency, reduces emissions, particularly particulate matter, and increases power consumption while minimizing fuel consumption, with the ability to auto-tune and adapt to varying engine conditions.

Implementation Method 1

The suction of the venturi is provided by the manifold vacuum or pressure difference

Methodology Applied
Scientific EffectVenturi effect: Venturi Effect

Data Source

PatentEP1971759B1Diesel fuel engine injection system & method therefor
Publication Date: 2020.09.02 DGT IP HLDG PTY LTD
  • EP1971759B1 patent drawingFigure 1
  • EP1971759B1 patent drawingFigure 2
  • EP1971759B1 patent drawingFigure 3

AI summary

There is provided a method of injecting LPG gas into a diesel fuel engine for combustion with diesel fuel therein. The method includes the steps of injecting LPG gas into an air-stream of an engine air intake or manifold, measuring the percentage of LPG gas injected into the airstream or other efficiency gauge, varying the rate of injection of LPG gas into the airstream in response to the measured percentage of LPG gas therein, and injecting the LPG gas at a pre-determined rate so as to maintain an LPG gas concentration in the air intake stream in the range of 0.2% to 0.6% by volume of LPG gas. Also provided is a system for injecting LPG gas into a diesel fuel engine for combustion with diesel fuel therein. The system includes an LPG gas injection device having an outlet disposed in fluid communication with a diesel fuel engine air-inlet and an inlet disposed in fluid communication with an LPG gas source, and an LPG gas injection device controller configured to receive input indicative of an engine performance parameter and configured to the control LPG gas injection rate from the LPG gas injection device outlet such that the diesel engine air-inlet has LPG gas injected therein to form an air-LPG gas mixture having an LPG gas concentration of between 0.2% to 0.6%.