Steam Generator Enveloping Bypass Channel for Waste Heat Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing steam generators for waste heat recovery in internal combustion engines face challenges in efficiently evaporating working media with varying heat demands, leading to potential overheating and increased production costs due to complex designs.
Innovation Solution
A steam generator design featuring a heat exchanger channel enveloping a bypass channel, with a coil-like heat exchanger and tubular housing, allowing for low flow resistance and reduced mechanical stresses, along with a control member for managing heat flow, and enhanced thermal insulation using metal foam, to optimize heat transfer and compactness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a heat exchanger is designed with high heat transfer area to ensure efficient evaporation of working medium, then heat transfer efficiency is improved, but the device complexity and manufacturing cost increase
Solution Approach 1:
The heat exchanger is nested within the housing structure, with the heat exchanger channel enveloping the bypass channel. This nested arrangement allows the heat exchanger to be integrated into the existing housing without requiring additional external components, thereby reducing device complexity while maintaining high heat transfer efficiency through the extended heat exchanger surface area.
Solution Approach 2:
The heat exchanger is configured in a coil-like manner that extends in multiple dimensions within the housing. This three-dimensional coiled structure maximizes the heat transfer surface area within the available volume, improving heat transfer efficiency without proportionally increasing the overall device footprint or complexity.
2Ease of manufacture
If a compact heat exchanger design is used to reduce device size and cost, then manufacturing cost is reduced, but flow resistance increases
Solution Approach 1:
The steam generator is divided into two separate channels: a heat exchanger channel for heat transfer and a bypass channel for flow. This segmentation allows the heating fluid to flow through a dedicated path with optimized geometry that minimizes flow resistance, while the heat exchanger channel provides sufficient heat transfer surface area without compromising the overall compact design.
Solution Approach 2:
The bypass channel acts as an intermediary flow path that connects the inlet and outlet of the steam generator, providing a low-resistance route for the heating fluid. This intermediary channel ensures that even with the compact heat exchanger design, the flow resistance remains acceptable by offering an alternative efficient flow path.
3Loss of energy
If the heat exchanger is tightly coupled with the housing to improve thermal insulation, then thermal insulation is improved, but mechanical stress increases
Solution Approach 1:
The heat exchanger is extracted as a separate component that can be independently positioned within the housing, rather than being permanently fused or tightly constrained. This extraction allows the heat exchanger to be thermally coupled with the housing for insulation purposes while maintaining enough freedom to accommodate thermal expansion and contraction, thereby reducing mechanical stress on the components.
4Reliability
If a bypass channel is added to reduce flow resistance and prevent overheating, then reliability is improved, but device complexity increases
Solution Approach 1:
The bypass channel is merged with the heat exchanger channel in a nested arrangement, where the heat exchanger channel envelops the bypass channel. This merging allows both channels to share the same housing space and structural support, reducing the overall increase in device complexity while still providing the reliability benefits of the bypass path for preventing overheating and managing flow resistance.
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
The design achieves efficient heat transfer, reduces the risk of overheating, and lowers production costs while maintaining high energy efficiency, enabling effective waste heat recovery in internal combustion engines.
Implementation Method 1
a heat exchanger (3) arranged in a heat exchanger channel (2), wherein the heat exchanger channel (2) envelops a bypass channel (4)... the heating fluid, which supplies the heat needed to evaporate the working medium, can be fed through the heat exchanger channel (2), so that it impinges on or flows around the heat exchanger (3) arranged therein
Implementation Method 2
enhanced thermal insulation using metal foam
Data Source
AI summary
A steam generator (1) is provided for a Rankine cycle, especially for a waste heat recovery device (37) of an internal combustion engine (36), and preferably in a motor vehicle. The steam generator includes: a heat exchanger channel (2), in which a heat exchanger (3) is arranged, and a bypass channel (4) for bypassing the heat exchanger channel (2). A heating fluid can flow through the heat exchanger channel (2) and bypass channel (4) during the operation of the steam generator (1). A medium to be evaporated can flow through the heat exchanger (3) during operation of the steam generator (1). A compact structural shape with high energy efficiency is achieved with the heat exchanger channel (2) enveloping the bypass channel (4).