Head Gasket Dam Structure for Uniform Engine Coolant Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The vertical flow method in internal combustion engines leads to a dispersion of coolant flow rates among cylinders, resulting in a lower flow rate towards the downstream cylinders, which affects the temperature balance and efficiency of the engine.
Innovation Solution
The implementation of dam portions in the head gasket, which are strategically placed downstream of the coolant opening portions to block the flow and increase the pressure of coolant upstream, thereby maintaining a consistent flow rate across all cylinders by backing up the coolant flow passage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the vertical flow method is adopted for coolant flow in the in-block water jacket, then the structure is simple and coolant flow is established, but the flow rate disperses among cylinders with lower flow rate towards downstream cylinders
Solution Approach 1:
The in-block water jacket is divided into multiple independent coolant flow passages, with each passage serving specific cylinders. This segmentation ensures that coolant flow is distributed evenly to each cylinder group rather than creating a dispersed flow pattern where downstream cylinders receive less coolant.
Solution Approach 2:
Different sections of the water jacket are designed with locally optimized characteristics - upstream sections have configurations that maintain pressure, while downstream sections have configurations that ensure adequate flow delivery. This local quality adjustment compensates for the natural pressure drop along the flow path.
2Ease of operation
If coolant flows sequentially through cylinder outer peripheral portions from upstream to downstream, then the flow path is straightforward, but the flow rate decreases towards downstream cylinders
Solution Approach 1:
Coolant is pre-cooled in dedicated passages before being distributed to cylinder outer peripheral portions. This preliminary cooling action ensures that coolant maintains its cooling effectiveness throughout the entire flow path, compensating for the natural temperature rise that would otherwise occur during sequential flow through multiple cylinders.
Solution Approach 2:
Intermediate coolant distribution passages act as mediators between the main coolant supply and the cylinder cooling passages. These intermediary passages regulate and redistribute coolant flow to ensure each cylinder receives adequate flow rate regardless of its position in the sequence.
3Ease of manufacture
If the in-block water jacket uses a standard configuration, then manufacturing is simple, but temperature balance of the cylinder block deteriorates
Solution Approach 1:
The water jacket is designed with locally varied cross-sectional areas and flow passage dimensions tailored to the specific thermal requirements of different cylinder positions. Upstream cylinders receive coolant through passages with larger cross-sections, while downstream cylinders have passages optimized for their lower flow rates, ensuring uniform temperature distribution across all cylinders.
Solution Approach 2:
Key parameters of the water jacket configuration - including passage cross-sectional area, passage length, and coolant velocity - are varied along the flow path to compensate for pressure drop and maintain consistent cooling effectiveness. This parameter optimization achieves temperature balance while keeping the overall structure manufacturable.
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 configuration effectively recovers the flow rate of coolant upstream of the dam portions, ensuring a consistent transfer from the in-block water jacket to the in-head water jacket, thereby preventing flow rate dispersion among cylinders and enhancing engine temperature balance.
Implementation Method 1
one or a plurality of dam portions 38 which block the flow of coolant are provided at positions downstream of the coolant opening portions 32
Implementation Method 2
the temperature of coolant in an in-block water jacket rises due to the transfer of heat from a cylinder bore inner wall
Data Source
AI summary
An internal combustion engine is equipped with a cylinder block having a plurality of cylinders and an in-block water jacket, a cylinder head having an in-head water jacket, and a head gasket. The in-block water jacket includes a plurality of cylinder outer peripheral portions. The head gasket includes a plurality of coolant opening portions. The internal combustion engine is configured such that coolant sequentially flows through the cylinder outer peripheral portions along a cylinder bank direction in the in-block water jacket. The head gasket includes one or a plurality of dam portions provided, in such a manner as to block the flow of coolant, at a position downstream of the coolant opening portion corresponding to the cylinder outer peripheral portion located at least most downstream in an in-block coolant flow direction.