NanoJet™ Eductor Nozzles

Why a 45° Upward Angle Near the Floor?

For maximum mixing efficiency and plume generation, NanoJet nozzles should be positioned 10–20 cm off the tank floor and oriented at a 45° upward angle. The upward trajectory directs the high‑velocity jet diagonally into the water column, creating a rising plume that avoids immediate wall or floor impingement. As the plume rises, it entrains surrounding water at a 10:1 ratio (entrained water : jet flow), generating a large, slow‑rising convection cell that enhances gas exchange across the entire tank.

45° Upward vs. 45° Downward – Both Are Relevant

Both angles can be combined (upward nozzles on one manifold, downward on another) depending on tank goals — for maximum off‑gassing and oxygen stability, the 45° upward orientation is preferred.

The Eductor Effect: Baseline Turbulence from Liquid Alone

A standard hydraulic eductor using unaerated water already generates significant turbulence by forcing liquid through a Venturi throat: velocities rise from <2 m/s to 15–25 m/s, entraining 3–5 parts ambient fluid per 1 part primary flow.

The NanoJet Advantage: Adding Bubbles to an Already Turbulent Base

The NanoJet starts with the 3–5× multiplier of a standard liquid eductor and adds nano‑bubbles (<200 nm) + micro‑bubbles (10–50 µm). The effect is synergistic, not merely additive.

Performance by Incoming Pressure: 2 Bar to 6 Bar

Higher pressure increases jet velocity, bubble shearing, and plume reach. The table below presents per‑nozzle performance across the operating range.

Nozzle Dimensions & Performance Curves

Configuration: Standard 25mm (1 inch) feed pipe. Interchangeable nozzle apertures from 5mm to 12mm diameter. Values shown at 4 Bar nominal operating pressure.

Performance Curves: Velocity vs. Pressure by Nozzle Size

Flow Rate Curves: L/min vs. Pressure by Nozzle Size

Nozzle Selection Guide by Application

Key Engineering Formulas

Why Higher Pressure Increases Bubble‑Induced Turbulence (BIT)

• Higher Reynolds number: Re ~ ρvD/μ at 6 Bar exceeds 2×10⁵ → fully turbulent eddy cascade.
• Energy dissipation rate (ε) ∝ v³/D: from 2 Bar (12 m/s) to 6 Bar (26 m/s), ε increases ~10×, producing intense bubble wake turbulence.
• Bubble density & size: 6 Bar yields up to 3×10⁷ bubbles/mL – three orders of magnitude higher than coarse bubble aeration.
• Slip velocity & Reynolds stresses: nano‑bubbles remain suspended with significant relative motion, adding turbulence absent in single‑phase flow.
• Smaller nozzle apertures (5-6mm): Increase shear rate, producing finer bubbles but reducing total flow. Best for deep tanks.
• Larger nozzle apertures (10-12mm): Maximize circulation and entrainment, ideal for shallow tanks and sludge suspension.

Off‑Gassing: How Larger Bubbles Strip Noxious Gases

Micro‑bubbles coalesce into larger bubbles (1–5 mm) as they rise. At the surface, these bubbles act as gas‑lift carriers, removing CO₂ → raises pH, H₂S (Hydrogen Sulfide) → highly volatile, transferred into rising bubbles, and excess Ozone (O₃) → off‑gassed to prevent residual oxidant damage.

The 45° upward angle maximizes vertical path length, allowing 30–50% higher stripping efficiency compared to 2 Bar operation, especially at 4–6 Bar.

The Final Condition: An Oxygenated, Stable Water Body

After off‑gassing, the water remains saturated with stable, long‑lived nano‑bubbles (half‑life weeks) due to high internal pressure (Young‑Laplace: ΔP = 2γ/r). Oxygen supersaturation >200% is achievable, preventing anoxic zones and maintaining aerobic biology across the tank. 5–6 Bar operation with 5-7mm nozzles maximizes nano‑bubble population and oxygen retention time.