🔬 DniproHES Francis Turbine and Generator: Interactive 3D Cutaway

About this simulation

DniproHES Francis Turbine and Generator: Inside a Ukrainian Hydropower Landmark

An interactive, illustrated mechanical study of a vertical-shaft Francis hydroelectric unit inspired by the engineering heritage of the Dnipro Hydroelectric Station in Zaporizhzhia, Ukraine.

Water, electricity and a turning point in Ukrainian industrial history

An enormous hydroelectric turbine is a strangely quiet idea made physical. A river holds gravitational potential energy because its upstream surface stands higher than the water below a dam. The power station provides a controlled route downhill, turning some of that stored energy into motion and then electricity. Inside the powerhouse, much of the work happens out of sight: beneath the generator floor and inside metal passages that must withstand substantial water pressures. This interactive exhibit opens those passages and places the turbine, generator and hydraulic controls in one inspectable three-dimensional assembly.

Our subject is connected to the Dnipro Hydroelectric Station, usually called DniproHES or DniproGES, beside Zaporizhzhia on the Dnipro River. Its early development belongs to the dramatic history of Ukrainian electrification and large-scale twentieth-century engineering. The mechanical arrangement shown here is a teaching reconstruction, not a laser scan or faithful copy of any particular surviving machine. We use historically grounded principles while making smaller parts, colours, accessible gaps and dimensions illustrative. A good museum reconstruction should help a visitor understand how a machine works without pretending that conjecture is original evidence.

A station on the Dnipro

The Dnipro was a natural route and resource long before the construction of the hydroelectric complex. The river's historic rapids around today's Zaporizhzhia constrained navigation and offered the possibility of substantial hydraulic head. The industrial project that became DniproHES began construction in 1927. The first generating units entered operation in 1932; the ceremonial opening of the station is associated with 10 October of that year. Ukrainian state archives preserve extensive photographs and film of the construction, including difficult working conditions, the installation work and the developing machine hall.

Ukrhydroenergo's historical account records that the initial stage included five hydro units rated at 62 MW apiece, producing an initial total of 310 MW. Historical engineering literature identifies the original large units as vertical-shaft Francis turbines. That combination—large water passages, rotating Francis runners, upright mechanical shafts and generators above—is the reason this particular device offers such a revealing museum cutaway. The numbers describe the historical station, not a performance guarantee for our stylised virtual assembly.

The context, and its human cost

DniproHES became a symbol of industrial modernisation, but it should not be reduced to a triumphant diagram of technology. Such works emerged under the Soviet system, with intense labour demands, profound social consequences and political control over industrial priorities. A serious history asks who planned, manufactured, installed, operated and maintained these machines, as well as whose lives and communities were affected by the transformation of the river. Engineering ambition and complicated human history can coexist in the same exhibition.

The station's later life also involved wartime damage, reconstruction and successive modernisation. Different equipment generations must therefore not be blended into a fictional single original machine. Our model deliberately treats the underlying Francis mechanism as the central subject and labels peripheral fittings as interpretative. The exhibit commemorates the engineering heritage situated in Ukraine without claiming that every visible bolt was present in the 1932 powerhouse.

Reading the vertical machine from bottom to top

Begin at the lowest level. A broad draft tube collects water leaving the runner and returns it to the downstream channel. Above it sits the runner: a sculpted bronze-coloured wheel with curved blades. Around the runner is a ring of adjustable wicket gates, enclosed by the spiral-shaped pressure casing. A tall shaft rises through supporting bearings. Finally, the shaft enters the generator, where a magnetic rotor spins inside stationary windings. The service floor and safety rails sit near the top of the arrangement.

These parts form a continuous energy pathway, but they do not all rotate. The runner, turbine shaft and generator rotor share angular motion. The turbine housing, bearings, guide-vane supports and stator remain stationary. Guide vanes make smaller controlled rotations about their own pivots to change the water admission. The distinction is central to both the engineering and the simulation's Operation mode.

1. The pressure inlet and scroll case

Water arrives from an upstream conduit commonly called a penstock. It has substantial pressure because of the elevation difference between the forebay and the tailwater. Rather than firing water against one side of a wheel, a Francis turbine distributes it around the perimeter of the runner. A scroll or spiral casing wraps around the machine, gradually changing its cross-section as water leaves it for the guide apparatus. The decreasing available flow around the spiral helps engineers maintain a suitable distribution to the inner passages.

On the model, follow the inlet branch into the blue-green volute. Individual casing sectors reveal the changing radius of the passage. Open Cutaway mode to remove the near side and inspect the guide-vane annulus. The cross-sections are visual abstractions, not a claim about the historic powerhouse's manufacturing drawings. Real volutes are carefully designed hydraulic structures rather than uniform decorative tubes.

2. Stay vanes, wicket gates and the governor

Water leaving the spiral casing passes fixed support elements and then adjustable guide vanes. Real turbine guide apparatuses combine structural support with careful hydraulic shaping. Each wicket gate turns about its own generally vertical shaft; the collective opening determines admission and the angle at which water approaches the moving runner. At small openings, a narrower flow passage limits discharge. A governor coordinates the gates so the unit responds to demand, operating conditions and protection systems.

Our twenty selectable teaching-scale gates and their pivot collars are arranged around the runner. Gold-coloured levers connect them conceptually to an operating ring, and blue actuator housings indicate how controlled motion can be imposed. Moving the Guide gate opening slider changes both the calculated discharge and the visible gate orientation. This is a physical relationship, not a purely decorative animation, although the displayed actuator geometry and the gate law are simplified.

3. The curved Francis runner

A Francis runner accepts flow with a radial component and redirects it toward an axial outlet. Its blades curve in three dimensions because they must manage both changing flow direction and changing velocity through the rotating passages. The resulting force creates torque about the vertical axis. In a real machine, designers optimise blade geometry against head, flow, speed, cavitation risk, hydraulic losses and mechanical stresses. Runner blades are not simple propeller paddles.

Our model's seventeen thickened curved blades connect an inner hub with circular crown regions. The selected metal colour makes their paths easier to read; it does not establish the alloy of a historical DniproHES runner. In Operation mode the runner rotates together with the generator rotor. The full view is intended to show their common shaft connection, while Cutaway mode makes the radial inlet and downward discharge easier to imagine.

4. The vertical shaft and bearings

The shaft is the mechanical bridge between hydraulic and electrical machines. Torque developed at the runner travels upward along the shaft into the generator rotor. Bearings resist the forces that would otherwise move the shaft sideways, and thrust-bearing arrangements in real vertical hydro units manage the large axial loads. Lubrication, sealing and alignment are crucial: a generator can be enormous, but a small error at a bearing can eventually become a serious reliability problem.

The exhibit includes shaft collars, bearing rings, support braces and inspection access. Some are enlarged for selection and comprehension. The bearings should not be understood as a complete engineering specification; actual bearing and thrust arrangements vary between turbine types and equipment generations. What matters mechanically is the distinction between the stationary supports and the shaft that turns inside them.

5. The draft tube: valuable work after the runner

The draft tube can appear secondary because it sits below the principal rotating wheel. It is actually a vital part of the hydraulic system. Water leaves the runner with remaining kinetic energy. As the diffuser broadens, average velocity can fall, allowing part of the kinetic head to appear as a useful pressure recovery. A well-designed draft tube improves the effective pressure difference experienced by the turbine, but careless geometry can create flow separation, unsteady forces and losses.

The tapered blue liner in the lower section is segmented for inspection. It is deliberately broad enough to convey the diffuser principle. The reconstruction does not resolve the complex swirling flow field that a real turbine can produce at part load. Computational fluid dynamics and scale-model testing are necessary to investigate that flow in an engineering project.

6. Electricity from a rotating magnetic field

The vertical shaft is connected to the generator rotor. A set of excited magnetic poles rotates inside stationary electrical windings. The changing magnetic flux seen by the stator conductors produces alternating electromotive force. The stator comprises iron and insulated copper conductors; the rotor carries the magnetic field. Our model shows a forty-pole teaching configuration to make the frequency calculation especially clear. It should not be taken as documentation of the historic unit's actual pole count.

With a synchronous generator, the frequency relationship is f = P × n / 120, where P is the number of magnetic poles and n is mechanical speed in revolutions per minute. Forty poles turning at 150 rpm produce 50 Hz. In an interconnected electrical grid, the generator must be synchronised and governed appropriately; a large hydro unit cannot freely choose any rotational speed while directly connected to a fixed-frequency grid.

7. Converting head and flow into power

The basic textbook expression for hydraulic power is P_hydraulic = ρ × g × Q × H. Here ρ is water density in kg/m³, g is gravitational acceleration in m/s², Q is volume flow in m³/s and H is the net hydraulic head in metres. The result is watts. To estimate electrical output, multiply by overall turbine-to-terminal efficiency η, then divide by one million to express megawatts.

In symbols: P_electric (MW) = ρgQHη / 1,000,000. The simulation uses 1,000 kg/m³ for water density and 9.81 m/s² for gravitational acceleration. Both are modelling conventions. Actual density varies with conditions, net head changes with flow and water levels, and efficiency varies with the operating point. Drag the head and efficiency sliders and observe how the displayed electric power changes.

8. Where the flow estimate comes from

Flow is not simply invented as an independent number. The interactive model estimates discharge using an orifice-like relation: Q = C_d × A_effective × sqrt(2gH), with a demonstration discharge coefficient of 0.90. The nominal maximum effective inlet area is 6.8 m², and the guide-gate percentage scales that area. In real Francis equipment, discharge curves depend on the coupled hydraulic behaviour of the wicket gates, spiral casing, runner and draft tube. A manufacturer would use measured hill charts or validated performance calculations.

Therefore the reading is a steady-state educational estimate, not DniproHES telemetry, a certified performance prediction or a tool for controlling machinery. Its merit is causality: changing a gate opening affects calculated volume flow, and changes in flow affect power, torque and the water-energy balance. It enables meaningful questions without pretending to solve the full Navier–Stokes equations.

9. A numerical experiment: the energy path

Set the head to 48 m, the gate opening to 76%, overall efficiency to 90%, and speed to 150 rpm. The orifice approximation gives a flow of about 140 m³/s. Multiplying the mass flow by gravitational potential energy per kilogram gives a hydraulic input of roughly 66 MW, and the efficiency estimate converts that to nearly 60 MW of electrical output. Small numerical differences arise from rounding at the displayed precision.

The power balance also has an independent computational route. Start with mass flow in kg/s, multiply by the specific potential-energy change gH in joules per kilogram, then apply efficiency. The script compares this result with the direct hydraulic-power expression. Agreement verifies consistent units and arithmetic, not the validity of the underlying approximation. The independent check guards against a surprisingly common educational mistake: confusing cubic metres per second with kilograms per second.

10. Torque and tip speed

Power alone does not describe the shaft's mechanical burden. For angular velocity ω = 2πn / 60 in radians per second, shaft torque is T = P / ω in newton-metres. The exhibit expresses it in kN·m, so visitors can see how a large power flow can correspond to immense torque at relatively modest rotational speed. At a fixed output, lower shaft speed implies greater torque; this is relevant to the heavy shafts and generator poles characteristic of low-speed hydroelectric machines.

The separate runner-tip-speed readout uses u = 2πrn / 60, with an illustrative outer runner radius of 1.58 m. This is the mechanical circumferential speed, not the water's velocity. Comparing water passage estimates with blade speed is a useful introduction to turbine velocity triangles, but detailed designs require relative flow angles and measured operating points.

11. Material choices and a believable reconstruction

The model uses a restrained materials palette to distinguish function. Bronze-toned curved blades visually separate the runner from the blue enamelled pressure shell. Steel rings and fasteners identify structural connections. Copper-coloured bundles show the generator winding paths; darker iron segments represent magnetic cores. Real components may use different alloys, castings, coatings and surface treatments, and our labels describe the material appearance or general family rather than certified 1932 bills of materials.

The finished GLB exports contain individually named meshes, not a single textured sculpture. Select a runner blade or guide-vane pivot and the inspector names its function and subsystem. That hierarchy also supports hiding and isolating individual elements, showing why mechanical clarity is often more educational than photorealistic dirt alone.

12. Using the five interactive modes

Complete begins with the entire assembly and a free-orbit view. Drag to rotate, scroll or pinch to zoom, and click a visible component to inspect it. Cutaway removes selected outer covering segments, preserving the internal machine geometry rather than replacing the exhibit with a flat diagram. Exploded uses a distance slider to spread actual parts outward; every component returns to its proper position at zero separation. Operation rotates the functional drivetrain and responds to guide gate changes. Assembly progresses through ten mechanical groups from foundation to service deck.

The viewer also offers Focus, Hide, Isolate and Restore controls. Automatic levels of detail are provided for slower devices, and explicit High, Medium and Low settings help classrooms compare smoothness and performance. Because this is a heritage model, engineering honesty takes precedence over artificially impressive component counts: the geometry exists for structural or explanatory reasons.

13. Preservation and looking closely

Hydropower history is material culture: drawings, construction photographs, machine-hall architecture, maintenance practices, tools and the knowledge of operating crews. The Ukrainian national archives and the plant operator provide valuable entry points into the documented history of DniproHES. A preserved or reconstructed unit can make invisible mechanisms legible, but the reconstruction must remain separate from primary evidence. The views and metadata in this exhibit are intentionally open about that distinction.

An interactive cutaway also contributes something that a photograph cannot provide by itself. It allows the visitor to rotate the unit, select one vane among many, trace the energy path, and explore how a generator's electrical frequency relates to mechanical speed. Used alongside original archival photographs, such an exhibit can support rather than supplant historical interpretation.

Ten frequently asked questions

Further reading and provenance

The historical context is supported by the following public sources. The geometry, explanatory writing, formulas, metadata, renders and software are original work created for this exhibit; the listed sources were not copied into the model.

• Ukrhydroenergo, history of DniproHES construction, commissioning and later development: https://uhe.gov.ua/media_tsentr/novyny/istoriya-dniprovskoi-ges-proektuvannya-budivnictvo-vidnovlennya-ta-sogodennya
• Central State Audiovisual and Electronic Archives of Ukraine, historical DniproHES photographic and film holdings: https://old.archives.gov.ua/Sections/Dniproges/
• Nature (1932), “Hydro-electric Power on the Dnieper”: https://www.nature.com/articles/130503c0
• CIGRE regional engineering history, discussion of the first Francis-type vertical-shaft turbine installation: https://bhkcigre.ba/Documents/monografije/SEERC_CIGRE_History_Knjiga_arhiv.pdf
• Leibniz Institute for the History and Culture of Eastern Europe, DniproHES machine hall record: https://ukrainian-destroyed-heritage.leibniz-gwzo.de/items/obj_028.html