Inline Air Pressure Attenuation for High-Rise Drainage Stacks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solutions for suppressing and alleviating pressure transients in building drainage systems, such as the PAPA™ system and surge tanks, are not effective for high-rise buildings as they require additional space and cannot be integrated directly into the drainage stack, leading to inadequate air pressure attenuation and noise issues.
Innovation Solution
A positive air pressure attenuation device integrated into the main drainage stack, featuring an elastic flexible inflatable reservoir that can withstand high pressures and is designed to be part of the vertical drainage pipe, allowing for in-line installation and effective attenuation of both positive and negative pressure transients.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing pressure attenuation devices (PAPA system, surge tanks) are used, then air pressure transients can be suppressed, but additional space and extra junctions are required, making them unsuitable for integration into drainage stacks
Solution Approach 1:
The pressure attenuation device is merged with the drainage stack by integrating the reservoir directly into the stack structure. The reservoir is positioned within the stack's cross-sectional area, allowing it to perform pressure attenuation functions without requiring separate installation space or additional junctions, thus resolving the contradiction between reliability and device complexity
Solution Approach 2:
The reservoir is nested within the drainage stack structure, utilizing the internal space of the stack. This nesting approach allows the pressure attenuation device to be housed within the existing stack geometry, eliminating the need for external mounting and reducing installation complexity while maintaining effective pressure suppression
2Reliability
If existing pressure attenuation devices are used, then some air pressure attenuation is achieved, but they are ineffective for high-rise buildings with large air volumes and high pressures
Solution Approach 1:
The reservoir is designed with a flexible, expandable structure that can dynamically increase its volume in response to high pressure transients. The reservoir walls are made of elastic material that allows expansion during pressure surges, enabling the device to handle large air volumes and high pressures in high-rise buildings without requiring a permanently large device volume
Solution Approach 2:
The device utilizes changes in the physical parameters of the reservoir (volume, pressure, elasticity) to adapt to different operating conditions. During normal operation, the reservoir maintains a compact state, but during pressure transients, it expands to accommodate large air volumes, thus resolving the contradiction between effectiveness for high-rise buildings and device volume
3Reliability
If a surge tank is placed in parallel to a draining pipe, then pressure surges can be controlled, but the inner pipe cannot be part of the draining system, preventing direct integration into the drainage stack
Solution Approach 1:
The reservoir is merged with the drainage stack to form a single integrated component. The reservoir becomes part of the main drainage path, allowing it to control pressure surges while simultaneously serving as part of the draining system. This eliminates the need for parallel placement and enables direct integration into the drainage stack, resolving the contradiction between reliability and adaptability
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 device reduces air pressure transients by up to 90% and safely dissipates large air volumes, while being compact enough to be installed within the drainage stack, effectively addressing the challenges faced by high-rise buildings and providing additional benefits like equalizing negative reflections.
Implementation Method 1
an elastic flexible inflatable reservoir (8) associated to the inner central portion (6) of the pipe (3A), the reservoir (8) being operable on a positive air pressure transient within the drainage system
Data Source
AI summary
A positive air pressure attenuation device (1) comprising:—a housing (3) with an inner central portion (6) forming a channel (7); and an elastic flexible inflatable reservoir (8) associated to the inner central portion (6), whereby the inner central portion (6) has a wall portion (60) with a plurality of openings (61) forming passages between the channel (7) and the reservoir chamber (8A).