Spa Nozzle Air Entrainment via Sharp Turn Geometry
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing spa nozzles and jets in the hydrotherapy industry have limited air entrainment rates, typically ranging from 0.3 to 1.5, and lack effective control over flow patterns, which restricts the range of tactile sensations that can be provided to users.
Innovation Solution
A spa nozzle design with specific geometric configurations, including a sharp turn in the water inlet conduit and a transition conduit with a diffuser, along with the use of fluidic oscillators for controlling air entrainment, to achieve higher air entrainment rates and temporal control of flow patterns.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional spa nozzle designs are used, then the device complexity is low, but the air entrainment rate is limited to 0.3-1.5
Solution Approach 1:
The nozzle is divided into distinct functional segments: a water inlet conduit with sharp turn, a transition conduit with specific length-to-diameter ratio, and an output conduit. This segmentation allows each section to perform its specific function optimally, with the sharp turn creating flow separation and the transition conduit controlling the reattachment and air entrainment process.
Solution Approach 2:
The invention specifies precise geometric parameters: the transition conduit length L should be 0.06-0.15 times the inlet diameter D, and the sharp turn angle should be 45-90 degrees. By optimizing these parameters, the nozzle achieves maximum air entrainment rates of 2.0-4.0 while maintaining manufacturability.
2Adaptability or versatility
If conventional nozzle designs are used, then the manufacturing is simple, but the range of flow patterns and tactile sensations is limited
Solution Approach 1:
The nozzle design creates dynamic flow patterns through the interaction of water flow with the sharp turn geometry. The flow separation and reattachment processes are inherently dynamic, allowing the nozzle to produce varying flow patterns and tactile sensations depending on operating conditions, while the geometry itself remains static and manufacturable.
3Quantity of substance
If air entrainment rate is increased, then the tactile sensations are enhanced, but the control over flow patterns is reduced
Solution Approach 1:
The nozzle design creates an inherent feedback mechanism where the air entrainment rate is self-regulated by the flow dynamics. As water flows through the sharp turn, the degree of flow separation and subsequent air entrainment is automatically controlled by the balance between inertial forces and pressure gradients, providing stable operation without requiring external control systems.
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 new design achieves air entrainment rates up to twice that of conventional nozzles, providing a wider range of flow patterns and tactile sensations, enhancing user experience and differentiation in the market.
Implementation Method 1
the water flow separates from the conduit wall downstream of the sharp turn to form a free jet
Implementation Method 2
the expanded jet then entrains air from the surrounding environment
Data Source
AI summary
An improved spa nozzle that is capable of entraining high air flow rates from the surrounding environment, said nozzle of the type having a water input conduit of diameter D, a flow output conduit having entry and diameter of DID, a transition conduit having a diameter of ID and a length of PL, and an air entrainment conduit, and wherein the following ratios are defined to describe the relative geometry of the nozzle: α=PL/(DID−ID), β=DID/ID and γ=D/ID, the improvement comprising: the water input, transition and output conduits being configured such that α is in the range of 1.3-5 and β is>1.9.