Fuel Injection Valve Inlet Geometry for Pressure Loss Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fuel injection valves for gasoline engines face challenges in minimizing pressure loss near the valve seat, leading to inefficient fuel intake and increased spread and adhesion of fuel, which affects exhaust performance and particulate matter generation.
Innovation Solution
A fuel injection valve design featuring injection holes with a long axis and short axis configuration, where the long axis intersects with the seat portion, reducing pressure loss and maintaining high fuel pressure within the injection holes to minimize spray spread and adhesion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a round chamfered portion is formed at the opening edge of the injection hole inlet, then peeling of fuel inside the injection hole is suppressed, but pressure loss in the vicinity of the valve seat is not sufficiently reduced
Solution Approach 1:
The injection hole inlet is formed with a curved surface instead of a sharp edge. Specifically, a portion of the inlet is rounded with a radius of curvature R1 (0.05-0.2 mm), creating a smooth transition that prevents fuel peeling while minimizing pressure loss. This curved geometry allows fuel to flow smoothly into the injection hole without abrupt directional changes.
Solution Approach 2:
Different regions of the injection hole inlet have different geometric properties. The inlet portion closest to the valve seat has a specific curvature radius R1, while other portions may have different characteristics. This localized optimization allows the rounded portion to suppress fuel peeling at the critical inlet region without unnecessarily increasing pressure loss in other areas of the injection hole.
2Ease of manufacture
If the injection hole has a circular cross section, then manufacturing is simplified, but fuel intake efficiency near the valve seat is insufficient
Solution Approach 1:
The injection hole has a circular cross-section overall for ease of manufacturing, but the inlet portion features a localized curved surface with radius R1. This combines the manufacturing simplicity of a circular hole with the flow efficiency of a curved inlet, allowing fuel to enter efficiently without complex overall geometry.
3Shape
If fuel pressure is reduced near the injection hole outlet, then fuel spray spread increases, but fuel adhesion to combustion chamber surfaces worsens
Solution Approach 1:
The curved inlet surface is designed to maintain high fuel pressure throughout the injection hole by reducing pressure loss at the inlet. This preliminary pressure maintenance ensures that when fuel reaches the outlet, sufficient pressure remains to control spray characteristics and prevent adhesion to combustion chamber surfaces.
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 fuel intake efficiency, suppresses fuel spread and adhesion, and improves exhaust performance by maintaining high fuel pressure and reducing particulate matter generation.
Implementation Method 1
at least one fuel injection hole among the plurality of injection holes is configured in a shape such that an injection hole inlet has a long axis and a short axis, and the long axis is directed in a direction in which an extension line intersects with the seat portion
Data Source
AI summary
An object of the present invention is to provide a fuel injection valve that can be used in a gasoline engine and can take fuel into an injection hole with a small pressure loss near a seat portion on which a valve is seated. Thus, the present invention provides a fuel injection valve for a gasoline engine which includes: a plurality of injection holes; and a seat portion that opens and closes a fuel passage to the plurality of injection holes in cooperation with a valve. At least one fuel injection hole among the plurality of injection holes is configured in a shape such that an injection hole inlet has a long axis and a short axis, and the long axis is directed in a direction in which an extension line intersects with the seat portion.