Flooded Evaporator Diffuser for Stable Refrigerant Distribution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Flooded evaporators face challenges in maintaining even refrigerant flow distribution during part load operations or varying conditions, leading to flow separation and inefficiencies due to changes in pressure differentials and refrigerant densities.
Innovation Solution
A heat exchanger with a refrigerant flow diffuser featuring a movable element and a stationary element, where the moving element adjusts under pressure forces to maintain constant pressure difference between the diffuser and the shell, ensuring optimal flow distribution across the diffuser length.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the diffuser geometry is optimized for full load operation, then refrigerant flow distribution is improved at maximal flow, but flow distribution deteriorates during part load operation
Solution Approach 1:
The patent applies the dynamics principle by making the diffuser geometry adaptive through a movable element that responds to pressure changes. The movable element shifts position based on the pressure differential between upstream and downstream sides, dynamically adjusting the opening geometry to maintain optimal flow distribution across varying load conditions. This transforms the static diffuser into a dynamic system that self-adjusts to different operating regimes.
Solution Approach 2:
The patent implements parameter changes by varying the opening geometry parameters (area, shape, position) in response to changing operating conditions. The movable element changes the effective opening parameters based on pressure differential, allowing the diffuser to adapt its geometric parameters to maintain optimal performance both at full load and part load operations.
2Productivity
If smaller section openings are provided in the entering section to preserve constant flow at high pressure, then flow distribution is improved at full load, but flow separation occurs at part load due to high variations in individual opening flows
Solution Approach 1:
The movable element dynamically adjusts the opening geometry in response to pressure differential changes. At part load, when pressure differential decreases, the movable element shifts to increase the opening area, preventing flow separation and maintaining stable flow distribution across all sections of the diffuser.
Solution Approach 2:
The system incorporates feedback through the pressure-dependent movement of the movable element. The pressure differential between upstream and downstream sides provides automatic feedback that drives the movable element to the appropriate position, ensuring flow distribution uniformity is maintained through self-regulation without external control systems.
3Productivity
If the diffuser geometry is fixed to optimize nominal operating conditions, then performance is improved at reference conditions, but performance deteriorates when operating conditions vary significantly from reference conditions
Solution Approach 1:
The diffuser transitions from a fixed geometry design to a dynamic geometry design where the movable element adjusts the opening configuration based on real-time pressure conditions. This allows the diffuser to maintain optimal performance across a wide range of operating conditions, not just at the reference design point.
Solution Approach 2:
The diffuser achieves multi-functionality by being able to operate optimally under both full load and part load conditions, as well as various intermediate operating states. The movable element enables the single diffuser structure to perform the function of multiple different geometric configurations, making it universally applicable across different operating scenarios.
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 solution ensures consistent refrigerant flow distribution across the heat exchanger, maintaining efficiency even during part load operations and varying conditions by dynamically adjusting the geometry of the diffuser openings in response to pressure changes.
Implementation Method 1
the moving element being movable with respect to the stationary element under action of a pressure force exerted by the refrigerant flow
Implementation Method 2
a pressure force exerted by the refrigerant flow so that the refrigerant flow going through the openings is adjusted
Implementation Method 3
the moving element is laid on the stationary element closing the openings
Data Source
AI summary
A heat exchanger, such as a flooded evaporator, comprises a shell extending along a longitudinal axis (X), an inlet pipe and an outlet pipe, through which respectively enters (F1) and exits (F2) a refrigerant flow, and a bundle of pipes crossing the shell along the longitudinal axis (X), and comprising a refrigerant flow diffuser provided inside the shell downstream the inlet pipe, the refrigerant flow diffuser extending along the longitudinal axis (X) and comprising openings through which the refrigerant flows. The refrigerant flow diffuser comprises a moving element and a stationary element, the moving element being movable with respect to the stationary element under action of a pressure force (FP) exerted by the refrigerant flow so that the refrigerant flow going through the openings is adjusted and a differential refrigerant pressure between refrigerant pressure downstream (P2) and upstream (P1) the refrigerant flow diffuser is kept constant.