Two-Stroke Engine Cylinder Rinsing with Offset Windows
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Two-stroke engines with cylinder return rinsing suffer from imperfect air or fuel filling, low volume efficiency, and uneven heat distribution, leading to reduced output and higher fuel consumption.
Innovation Solution
A two-stroke combustion engine design featuring exhaust and rinse windows on the cylinder perimeter, with a rotary bushing controlling throttling openings to optimize air and fuel intake and exhaust, ensuring better cylinder filling and pressure distribution through angularly offset windows and openings on the piston.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If return rinsing of the cylinder is used in conventional two-stroke engines, then the cylinder is rinsed with fresh air or fuel mixture, but the rinsing is imperfect and volume efficiency is low
Solution Approach 1:
The invention divides the single rinsing process into two separate processes: exhaust gas removal through exhaust windows and fresh air intake through rinse windows. This segmentation allows each process to be optimized independently, with exhaust windows positioned to efficiently remove gases and rinse windows positioned to effectively introduce fresh air, thereby improving both cylinder filling quality and volume efficiency.
Solution Approach 2:
The invention introduces a water jacket as an intermediary element between the cylinder and the external environment. The water jacket serves as a heat exchange medium that absorbs heat from the cylinder walls during exhaust and releases it during rinsing, improving the thermal management and enhancing the efficiency of both exhaust and rinsing processes.
2Quantity of substance
If return rinsing of the cylinder is used, then the cylinder is rinsed with fresh air or fuel mixture, but heat load distribution is uneven
Solution Approach 1:
By separating exhaust and rinsing functions into distinct windows and channels, the invention enables independent optimization of thermal management. The exhaust windows are positioned and timed to remove hot gases efficiently, while the rinse windows are positioned to introduce cooler fresh air at optimal locations, creating more uniform heat distribution across the cylinder and piston surfaces.
Solution Approach 2:
The water jacket acts as a thermal intermediary that buffers and redistributes heat loads. It absorbs excess heat from hot spots on the cylinder walls during exhaust and releases heat to cooler areas during rinsing, thereby equalizing the temperature distribution and reducing thermal stress.
3Power
If conventional exhaust and rinsing methods are used, then the engine operates, but output is lower and fuel consumption is higher
Solution Approach 1:
The separation of exhaust and rinsing functions improves the efficiency of each process. Better exhaust gas removal ensures more complete combustion, while improved fresh air intake ensures adequate oxygen supply for combustion. This leads to more efficient fuel utilization, higher engine output, and lower fuel consumption.
Solution Approach 2:
The water jacket improves thermal efficiency by reducing heat losses to the environment and redistributing heat within the system. This thermal management enhancement improves combustion efficiency and reduces fuel consumption while maintaining or increasing engine output.
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 design enhances cylinder rinsing with fresh air, improves volume efficiency, and reduces fuel consumption by ensuring uniform heat load and efficient combustion, resulting in increased output.
Implementation Method 1
the perimeter of the cylinder is provided with at least one row of exhaust windows that lead to the exhaust channel positioned outside the cylinder perimeter and under the exhaust windows with at least one row of rinse windows that lead to a rinse channel positioned outside the perimeter of the cylinder
Implementation Method 2
the bushing being provided on its perimeter with at least one row of throttling exhaust openings and under them with at least one row of throttling rinse openings, wherein the bushing can be slewed in a controlled way
Implementation Method 3
a two-stroke combustion engine for use in a car, motorbike, sports and tourist aircraft or as a drive of industrial units
Implementation Method 4
a piston mounted in the cylinder the principle of which is that the perimeter of the cylinder is provided with at least one row of exhaust windows
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A two-stroke combustion engine is designed for rinsing via the combustion space (15) in the engine piston (3) through the centre of the cylinder (2) towards the top dead centre and subsequent forcing of the exhaust gas to the walls of the cylinder (2) and the exhaust. This manner of cylinder (2) rinsing is enabled by the cylinder {2) perimeter being fitted with exhaust windows (8) that lead to the exhaust channel (7) in the cylinder block (12) and rinse windows (10) positioned under them that are preferably angularly offset with regard to the exhaust windows (8) by a half of their spacing and lead to the rinse channel (11) in the cylinder block (12). The piston (3) includes combustion space (15) and inclined rinse openings (9) distributed on its perimeter and leading to the combustion space (15). When the piston (3) is in the bottom end centre, the rinse openings (9) interconnect the combustion space (15) with the rinse windows (10). The spark-ignition version of the engine may be provided with a bushing (16) mounted in a rotary way on the cylinder (2) and provided with throttling exhaust and rinse openings (17) and (18) whose rotation may change the timing of the exhaust and rinse of the cylinder.