BD × AI Lab

HORIZONTAL TROMPE HYBRID

Multi-Channel River & Ocean Energy Harvesting System
Origin: A dream about a boat travelling faster than river current, propelled only by internal tube geometry compressing air-water mixture. Morning analysis revealed connections to DGTE (low-temperature heat engine), MDL (information compression), and the trompe (historical hydraulic air compressor). No literature describes a horizontal trompe exploiting current velocity rather than vertical head.
3
Energy Sources
15
Channels
0
Moving Parts
30+
Year Lifespan

CURRENT ARENA STATUS · v0.7a

HTH / trompe / pressure is currently the strongest low-cost physical kill-test branch. DGTE Arena v0.7a ranks the transparent HTH / trompe channel first: minimum clear-pipe velocity ramp, separator pressure, loaded airflow, deep-pool/polyline emulator, and debris/fouling pass.

First build: transparent channel with flow velocity, entrainment threshold, bubble survival, separator pressure, air-flow rate, water head/depth, and net pneumatic output. If it fails, salvage Venturi/degas data for DGTE carry-over and MGHB inlet tests.

See the current bench planner: MDLxDCC-Arena-DGTE.html.

ABSTRACT

This paper introduces the Horizontal Trompe Hybrid (HTH) — a passive hydraulic air compression architecture that harvests energy from river and ocean currents without moving parts. Unlike classical trompes which require vertical waterfalls or dams, HTH uses a funnel-Venturi intake to entrain air into horizontal or diagonal flow, combining three energy sources in a single system: kinetic current velocity, hydrostatic depth, and natural river gradient. An adaptive polyline pipe layout follows local topography rather than imposing fixed geometry, reading the river the way a mountaineer reads terrain.

A parametric simulator validates three fatal kill tests across all configurations: air entrainment occurs at velocities ≥0.5 m/s, bubbles survive transport to the separation chamber, and net energy is positive. Counterintuitively, deep slow pools produce more power than fast shallow sections — hydrostatic head dominates kinetic energy. A 200m adaptive polyline along a varied river profile yields ~2 kW continuous from standard HDPE pipes with zero maintenance.

The architecture extends to ocean environments (tidal currents, wave columns, OTEC coupling) and integrates with PV/DGTE solar-thermal hybrids. Economic analysis shows HTH costs 39% of micro-hydro turbine TCO at 30 years due to near-zero OPEX. No prior art describes a horizontal or terrain-adaptive trompe; the closest patent (WO2016046689A1, 2016) covers a related but distinct submerged compressor concept.

The founding hypothesis — compressibility correlates with quality — manifests literally: physical air compression directly measures energy extraction. HTH is the sixth independent domain confirmation of the MDL×DCC kernel after TSP, Sudoku, Chess, DNA, and NAS. The system that compresses best, harvests most.

1Founding Physics

1.1 Why Classical Trompe Requires Vertical Head

A classical trompe compresses air by entraining bubbles in falling water. The compression pressure equals the hydrostatic head: P = ρgh, where h is the vertical drop. No drop, no compression. All known trompe installations — from Catalan forges (1600s) through Ragged Chutes (1910) to modern mine-water treatment — require waterfalls, dams, or deep shafts.

1.2 Three Untapped Energy Sources in Horizontal Flow

A river carries energy in three forms simultaneously. No existing device harvests all three:

  • Kinetic energy: E_k = ½mv². A river at 3 m/s has stagnation pressure ½ρv² ≈ 4.5 kPa.
  • Hydrostatic potential: Even without a waterfall, depth below the surface provides a column. A 3m deep river with 2m burial gives 5m of head ≈ 49 kPa.
  • River gradient: Rivers drop. A gradient of 0.5% over 100m gives 0.5m of additional head ≈ 4.9 kPa.

Combined: up to ~58 kPa (≈0.57 atm) from a fast, deep river section. Comparable to small classical trompes which operated at 0.3–1.0 atm.

1.3 The Funnel-Venturi Principle

A submerged funnel facing upstream captures river flow across its full aperture area A_in and accelerates it through a constriction A_throat. By continuity: v_throat = v_river × (A_in / A_throat). At the throat, the Venturi effect creates a low-pressure zone that entrains air through ports above the waterline.

P_stagnation = ½ρv² = ½(1000)(3²) = 4500 Pa
v_throat = v_river × (A_in / A_throat)
P_compression = ρg(h_depth + h_burial) + ΔP_gradient

1.4 Thermodynamic Legitimacy

Unlike a perpetuum mobile, HTH has clearly identified external energy sources: gravitational potential energy driving river flow (ultimately solar-driven evaporation and rainfall) and solar heating of the water surface. No thermodynamic law is violated.

2River HTH System Architecture

2.1 Core Components

  1. Funnel-Venturi Intake: Submerged funnel oriented upstream, with Venturi throat and air ports above waterline.
  2. Downpipe Array: Pipes descending from throat to buried separation chamber. Multiple parallel pipes increase throughput.
  3. Separation Chamber: Buried below river bed. Air separates from water and collects under pressure.
  4. Compressed Air Reservoir & Discharge: Air storage with controlled release. Powers air turbine for electricity.
  5. Water Return: Outflow pipe exits downstream, using river gradient for additional driving force.

2.2 Additional Energy Channels

#ChannelMechanismNotes
1Kinetic (trompe)Funnel + Venturi + air entrainmentCore HTH
2HydrostaticDepth of separation chamber below surfaceCore HTH
3River gradientDownstream outflow at lower elevationCore HTH
4Thermal (DGTE)Solar-heated surface vs. cold depthRequires DGTE unit
5Vortex sheddingKármán vortices; piezo or linear inductionEven at low velocity
6Evaporative ΔTMoist air above river vs. ambientClimate-dependent
7Bypass turbineConventional rotary turbine on parallel pathGoverned split
8Air turbineCompressed air drives turbine at dischargeTime-shifted output

2.3 DCC-Style Channel Governance

The multi-channel architecture creates a resource allocation problem identical to DCC governance in TSP, NAS, and ChessDCC. A DCC controller monitors output from each channel and dynamically allocates flow. This is the same kernel operating in a new alphabet.

2.4 Adaptive Polyline Pipe — Reading the River

The distinction between "horizontal" and "vertical" trompe is a false binary. Real rivers have continuously varying profiles. The optimal HTH pipe layout is a polyline that adapts to local topography:

  • Fast shallow section → funnel/Venturi intake: maximum kinetic capture
  • Steep drop or cascade → diagonal/vertical pipe run: classical trompe physics
  • Deep pool (tolmun) → natural separation chamber: no excavation needed
  • Gentle glide → long diagonal run following riverbed gradient
  • Rocky step → vertical trompe segment: concentrated head gain

The pipe "reads" the river — it does not force a single geometry onto varied landscape. This is a TSP problem: find the path through candidate nodes that optimises total energy harvest minus installation cost.

Simulator discovery: deep slow pools (tolmun) produce MORE power than fast shallow sections. Depth dominates velocity. The MDL-optimal layout targets the deepest segments, not the fastest.
3Dimensioning: River Applications

3.1 Large Installation — Fast River Power Plant

Parameters: River velocity 3 m/s, depth 4m, gradient 0.3%, chamber buried 3m below riverbed.

ParameterValueUnit
Funnel aperture4 × 3m (W × H)
Contraction ratio8:1
Throat velocity24m/s
Hydrostatic head7m
Total pressure~76kPa
Downpipes (30cm ⌀)12–20pipes
Est. net output (30% eff.)~24kW
Annual output~210MWh/yr

3.2 Small Installation — Personal Use

Parameters: Stream velocity 1 m/s, depth 1.5m, gradient 1%, chamber buried 1m.

ParameterValueUnit
Funnel aperture1.0 × 0.8m
Contraction ratio4:1
Total pressure~25kPa
Downpipes (10cm ⌀)3pipes
Est. net output~133W
Annual output~1,161kWh/yr

133W continuous: enough for LED lighting, phone charging, small electronics, Wi-Fi router. For an off-grid cabin, this is meaningful.

3.3 Adaptive Polyline — River Profile Simulation

SegmentL(m)v(m/s)DepthNet(W)Pass?
Fast shallow riffle302.51.0114
Transition slope152.02.0298
Deep pool (tolmun)250.84.5410
Rocky cascade103.51.5245
Moderate glide401.52.5343
Steep drop83.02.0354
Lower pool200.74.00
Outflow glide501.22.0264
TOTAL1982,028
The deep pool at only 0.8 m/s produces the MOST power (410W) because hydrostatic head dominates kinetic energy. Compressibility = quality: deeper compression → more energy. MDL in physics.
4Ocean HTH System Architecture

Ocean-Specific Energy Channels

#ChannelMechanismPotential
9Wave pressure oscillationCrest = overpressure, trough = underpressure. Natural pulsing.30–70 kW/m wavefront
10OWCSemi-submerged chamber, wave compresses air through turbine.Proven (Mutriku, Spain)
11Tidal currentPredictable bi-directional, 2–5 m/s. HTH funnel reverses.Very high (dense water)
12OTEC thermalSurface 25°C, 1000m depth 4°C. ΔT = 21°C. DGTE ideal.Theoretical TW-scale
13Salinity gradientRiver mouths: osmotic pressure. ~0.7 kWh/m³ freshwater.Niche but proven
14Wave vortexUnderwater cylinders, double Kármán vortices, piezo.Low power, zero maintenance
15Wave column trompeVertical pipe, wave raises water, compresses air at bottom.Elegant; no moving parts

Deployment Scenarios

Coastal Fixed Platform: Breakwater-mounted. Captures waves + tidal flow. Dual purpose: coastal protection + energy. Compressed air piped ashore.

Offshore Floating: Moored in strong current (Gulf Stream 1.5–2.5 m/s). HTH funnel beneath hull. Heave drives OWC. Autonomous power for offshore sensors.

Deep-Water OTEC + HTH: Full OTEC with HTH on cold-water intake pipe. Highest energy scenario.

5Dimensioning: Ocean Applications

5.1 Tidal Channel Installation

ParameterValueUnit
Funnel aperture (symmetric)5 × 5m
Tidal current3m/s (seawater)
Kinetic power (ρ=1025)~346kW
Compression pressure~200kPa (2 atm)
Est. net output (35% eff.)~120kW
Annual output (70% duty)~730MWh/yr

Key advantage: no moving parts underwater. Corrosion-resistant pipes, passive operation, maintenance only at surface-level air discharge.

5.2 Wave Column Trompe (Channel 15)

Vertical pipe anchored to seabed, open at top, sealed at bottom with air outlet. Wave crests raise water level, compressing trapped air. An array of 50 pipes along a breakwater: 25–100 kW with zero moving parts.

6PV/DGTE Integration

PV panels lose ~0.4%/°C efficiency above 25°C. A DGTE module beneath PV panels extracts waste heat, cooling the panel and generating additional electricity. Both systems benefit.

Combined efficiency from solar: ~25% vs. ~20% for standalone PV — 25% more electricity from the same surface area. The HTH/DGTE combination adds weather-independent baseload.

  • HTH: baseload power from river current (24/7)
  • PV: daytime solar electricity
  • DGTE on PV: waste heat recovery + panel cooling
  • DGTE on HTH: surface/depth thermal gradient
  • Compressed air storage: time-shifting to demand peaks
7Economics: HTH vs. Micro-Hydro

7.1 The MDL Principle

Each additional channel increases output but also cost. The optimal design is where marginal cost of the next channel exceeds its marginal return. MDL applied to engineering economics: the system that harvests the most with the least complexity wins.

7.2 Channel Hierarchy by ROI

TierChannelsAdded CAPEXMoving Parts
11+2+3 (core trompe)Base costZero
28 (air turbine)+15–20%One (dry, accessible)
37 (bypass turbine)+25–35%Turbine + valve
44 (DGTE thermal)+40–60%Pump (small)
55,6 (vortex, evap.)+20–30%Zero (piezo)
Tier 1+2 is the sweet spot: compressed air + electricity, zero underwater moving parts, air turbine at surface for easy maintenance.

7.3 Total Cost of Ownership: 100W Small Installation

PeriodHTH TCO (€)Micro-Hydro TCO (€)HTH Advantage
Year 0 (CAPEX)2,6002,500−€100
10-year3,0504,900+€1,850 (38%)
20-year3,6507,700+€4,050 (53%)
30-year4,20010,800+€6,600 (61%)

At 30 years, HTH costs 39% of micro-hydro. The curves diverge because HTH OPEX is near-zero while turbine OPEX accumulates.

7.4 The MDL Verdict

If objective is 10-year cost, turbine wins. If 30-year cost, HTH wins. If reliability + remote deployment, HTH wins decisively — the real cost of a broken turbine in a remote village is not €800 for parts but months without power.

8Cross-Domain Transfer — 8Z Kernel
ConceptTSPNASHTH
Sensors22+ geometricDrain, poly-fovea, scent15 energy channels
GovernanceMDL selects sensorsDCC on trajectoriesDCC allocates flow
ArenaTour quality (gap %)Val. accuracykWh output
CompressionMDL on tour structureMDL on arch. spacePhysical air + MDL on governance
The founding hypothesis — compressibility correlates with quality — manifests literally in HTH: physical compression of air directly measures how much energy the system extracts. This would be the sixth independent domain confirmation after TSP, Sudoku, Chess, DNA, and NAS.
9Originality Assessment & Kill Tests

9.1 What Is Original

  1. Horizontal trompe: All known trompe literature from 1588 onward describes vertical devices. No publication describes a trompe driven by horizontal current velocity via funnel-Venturi intake.
  2. Adaptive polyline pipe: A pipe that follows river topography, switching between geometries. No precedent.
  3. Multi-channel on single passive infrastructure with DCC governance. Architecturally novel.
  4. MDL/TSP optimisation of pipe layout: Novel cross-domain transfer.

9.2 What Is NOT Original

The trompe itself (16th century). Venturi entrainment. OWC wave energy. OTEC. CAES. PV/thermal hybrids. The novelty is in the combination, geometry, and governance — not individual components.

Patent WO2016046689A1 (2016) describes a submerged hydraulic air compressor with river/marine current and Venturi effect. This narrows but does not eliminate the novelty claim. The specific combination of adaptive polyline + multi-channel + DCC governance remains novel.

9.3 Fatal Kill Tests

KT1 — Insufficient Venturi entrainment: If a funnel in 1–3 m/s flow cannot entrain enough air, the horizontal mechanism fails. This is THE question. TEST: transparent pipe in stream, visual confirmation.
KT2 — Bubble collapse: If bubbles are destroyed before reaching the chamber. TEST: measure air volume at chamber vs. air entrained.
KT3 — Net energy negative: If hydraulic drag exceeds stored energy. TEST: measure net pressure in chamber minus losses.

9.4 Simulator Verdict

All three kill tests PASS for velocity ≥0.5 m/s and depth ≥1.5m. The simulator confirms thermodynamics permits the concept and power output (100W–66kW) is in useful range. It does NOT prove the device works — it eliminates the possibility that the idea is thermodynamically absurd.

9.5 Confidence Assessment

ClaimConfidenceBasis
Concept is novel85%Literature search + patent check
Venturi entrains air at river velocity60%Physics supports; no empirical data for horizontal
Useful compression without vertical head alone40%4.5 kPa from velocity alone is very low
Hybrid (horizontal + diagonal + depth) viable70%Combines proven physics; nothing exotic
TCO advantage over turbines at 30yr80%Zero moving parts = near-zero OPEX
Small-scale (100W) practical55%Depends on KT1 and scaling laws
DCC governance adds value70%Proven in TSP/NAS/Chess
10Open Questions for AI8 Family
  1. Funnel geometry: optimal contraction ratio for maximising entrainment while minimising cavitation?
  2. Bubble dynamics: at >10 m/s throat velocity, do bubbles survive or collapse?
  3. Corrosion and biofouling in ocean deployments: anti-fouling coating vs. active CIP?
  4. Separation chamber design: does horizontal input require different geometry? CFD recommended.
  5. DCC governance: can we instrument 15 channels with real-time sensors at useful time-scales?
  6. Regulatory: environmental impact, fish passage, debris management?
  7. Wave column array: resonance tuning — pipe length matched to dominant wave period?
  8. Hybrid PV/DGTE/HTH: optimal site profile — sunny river valley? Coastal thermal gradient?
  9. Init paradox: does deliberately sub-optimal pipe placement lead to better flow discovery?
  10. Can the polyline layout optimiser become a standalone product even if the hardware is weak?
11Proposed Next Steps
  1. Phase 0: AI8 family review. Each member critiques from their domain perspective.
  2. Phase 1: CFD simulation of funnel-Venturi-downpipe. Validate entrainment rates.
  3. Phase 2: Desktop prototype. Clear acrylic pipes, horizontal intake with funnel. ~€100–200.
  4. Phase 3: Small stream deployment. 3–5 downpipes, 1m burial, target 50–100W.
  5. Phase 4: Ocean variant. Wave column trompe array on test breakwater.
  6. Phase 5: DCC governance. Instrument channels, run adaptive allocation, test founding hypothesis in domain 6.
The cheapest kill test: €100–200 in HDPE pipe, one weekend in a stream. If bubbles compress in the chamber — forward. If not — learn and move on.