Codex Energy Gas Turbine

Gas Turbine

The Gas Turbine burns fuel gas in a Brayton cycle: compressor, combustion, turbine and generator along one shaft. It is the high-power gas plant of tier II. Half of the fuel's heat leaves as hot exhaust, which Heat Ports hand to an Industrial Boiler: with a steam turbine behind it that is a combined-cycle power plant.

How it works

1. The compressor delivers the air: each Compressor Blade allows 75 mB/t of fuel.
2. The combustion liners burn the fuel: each Combustion Liner up to 150 mB/t. The fuel flow is the smallest of the fuel setpoint, the liners, the compressor and the fuel in the tank.
3. Heat = fuel × the gas's heat per mB.
4. The turbine blades turn up to 0.45 of that heat into rotor energy (times the blade efficiency, which is 100 % at the rated speed), but at most 450 E/t per Rotor Blade.
5. The generator takes the energy out of the rotor: each Generator Coil up to 600 E/t at the rated speed of 3,600 rpm, less at lower speed.
6. Exhaust: 0.5 of the heat leaves as hot exhaust through the Heat Ports. What no Heat Port takes in the tick goes up the stack.

Building

Shown size: 5 wide, 5 high, 7 deep (adjustable: Width 5–15, Height 5–15, Depth 6–16).

One example of many: within the rules on this page, size and arrangement are up to you; the Build Projector shows the plan in every allowed size.

	Key	Block	Count
	A	Gas Turbine Casing	118
	B	Industrial Sight Glass	8
	G	Rotor Blade	8
	D	Rotor Shaft	5
	E	Combustion Liner	4
	C	Compressor Blade	4
	H	Generator Coil	2
	J	Energy Output Port	1
	F	Gas Input Port	1
	I	Heat Port	1
	0	Gas Turbine Controller	1

Step by step

Each picture adds one layer, from the bottom up; the newest layer is bright. The controller wall faces you on the left.

Step 1: Layer 1

Parts in this step: Gas Turbine Casing (A) ×35

Step 2: Layer 2

Parts in this step: Gas Turbine Casing (A) ×17, Industrial Sight Glass (B) ×2, Rotor Blade (G) ×2, Combustion Liner (E) ×1, Compressor Blade (C) ×1, Gas Turbine Controller (0) ×1, Generator Coil (H) ×1

Step 3: Layer 3

Parts in this step: Gas Turbine Casing (A) ×15, Rotor Shaft (D) ×5, Rotor Blade (G) ×4, Industrial Sight Glass (B) ×3, Combustion Liner (E) ×2, Compressor Blade (C) ×2, Gas Input Port (F) ×1, Heat Port (I) ×1

Step 4: Layer 4

Parts in this step: Gas Turbine Casing (A) ×17, Industrial Sight Glass (B) ×3, Rotor Blade (G) ×2, Combustion Liner (E) ×1, Compressor Blade (C) ×1, Generator Coil (H) ×1

Step 5: Layer 5

Parts in this step: Gas Turbine Casing (A) ×34, Energy Output Port (J) ×1

Rules

• Size: at least 5 wide, 5 high and 6 deep, at most perf.maxStructureSize (default 16, allowed 5–32) in every direction. Width and height must be odd.
• Edges and corners: only Gas Turbine Casing.
• Walls: Gas Turbine Casing, Industrial Sight Glass, Inspection Hatches, the ports and the controller.
• Controller: in a wall face, front facing out, with the inside behind it. The wall with the controller is the front: the shaft runs from it to the back wall.
• Shaft: the centre line of the inside, front to back, is all Rotor Shaft.
• Stages: around the shaft, the slices of the inside (the layers across the shaft) must follow this order from the front: compressor blades → combustion liners → rotor blades → generator coils. Each stage needs at least one block, a slice may hold only one stage, and slices with only air may lie in between.
• Ports: Gas Input Port (fuel gas and oxygen), Energy Output Port, Heat Port (exhaust heat out). Any number, in wall faces; each works only on its outer face.

Fuel

Gas	Heat per mB (HU)	compressed
Natural gas	8	10
Hydrogen	6	7
Syngas	4	5

• The turbine takes every gas that burns, also compressed gas from the Gas Compressor, which gives about a quarter more heat. Syngas comes from the Gasifier, natural gas from the Gas Derrick, hydrogen from the Electrolyzer.
• Oxyfuel: with oxygen in its oxygen tank (16,000 mB), 1 mB of oxygen for every 2 mB of fuel, the heat is 1.25 times higher. Without enough oxygen for the whole fuel of the tick, it burns with air.
• The tank holds one gas at a time.
• The server's volt.fuelConsumptionMultiplier (default 1.0, allowed 0.01–100.0) makes it burn more gas for the same heat.

Sizing: compressor, liners, blades, coils

• Compressor and liners: one liner burns as much as two compressor blades allow. Two compressor blades per liner use the liners fully.
• Rotor blades: each blade carries up to 450 E/t of shaft power. Eight blades are plenty for the fuel of four liners.
• Coils: the rotor only reaches its rated speed when the coils fit the shaft power. Plan about one coil per 600 E/t of shaft power, where shaft power = fuel × heat per mB × 0.45.

For the fuel of the example (four liners and four compressor blades allow four times 75 mB/t):

Fuel	Heat (HU/t)	Shaft power (E/t)	Best coils	Output (E/t, about)
Natural gas	2,400	1,080	2	1,036
Compressed natural gas	3,000	1,350	2	1,200
Hydrogen	1,800	810	1 or 2	600
Syngas	1,200	540	1	505

• Too many coils hold the rotor far below its rated speed, the blades work badly and the output collapses; the screen says "Generator overloaded: fewer coils or more steam/fuel". With four coils a 5×5 turbine gives only about a quarter of what two coils give on natural gas.
• Too few coils cannot take all the energy: the rotor runs above its rated speed, the blades lose efficiency, and with even less load it reaches the overspeed trip.

Tip

The Build Projector counts the coils The example and the Build Projector place as many coils as natural gas at full fuel flow carries at rated speed: two for the 5×5 example, the free places of the coil slice stay air. For syngas take one of them out (see the table).

Operation in depth

• Fuel setpoint: the - and + buttons change it by 5 mB/t, from 0 up to the most the liners and the compressor allow.
• Generator I/O engages or disengages the coils, as in the Steam Turbine.
• Inertia grows with compressor and turbine blades, coils and shaft; the rotor spins up slowly and coasts down slowly.
• Overspeed: above 4,200 rpm a warning sign appears and the status says "Overspeed: …". At 4,800 rpm the overspeed trip closes the fuel valve until the rotor is back below 3,600 rpm. The S button switches the trip off, at the risk of a rotor burst; with safety.safeMode (default false) it stays on. See Incidents.
• A full buffer stops the coils from taking energy; the rotor then speeds up and trips. That is normal when nobody takes the energy.
• The server's volt.generatorOutputMultiplier (default 1.0, allowed 0.01–100.0) scales the output.

Combined cycle

Put a Heat Port into the turbine's wall and the Heat Port of an Industrial Boiler right against it, face to face. The boiler takes up to 40 HU/t per Heat Exchanger Tube and makes one mB of steam from every HU, which a Steam Turbine turns into about one E.

• Natural gas at full flow in the example gives half of its heat (see the table above) as exhaust; a boiler with 30 tubes (30 × 40 HU/t) takes all of it.
• Per mB of natural gas: about 3.6 E from the gas turbine plus 4 HU exhaust, which become about 4 E in the steam turbine.
• A Stirling Generator or a Foundry can also take the exhaust heat.

The screen

• Status: "Running", "Stopped", "Overspeed: …", "Tripped (overspeed): fuel cut off", "Generator overloaded: …" or the structure error.
• Bars for Fuel (with the name of the gas) and Energy.
• Speed, Fuel flow, Fuel setpoint, Power, Blade efficiency (0.45 times the blade efficiency: what share of the heat reaches the rotor), Exhaust heat (HU/t), Generator, Protection and Oxygen (oxyfuel +25 %).
• The diagram: compressor → combustion (heat) → rotor → generator (power), and combustion → exhaust → boiler (the heat a Heat Port handed on).
• Buttons: - and + for the fuel setpoint, I/O for the generator, S for the trip.

Error messages

Message	What to do
The controller must sit in a wall, front facing out	Put the controller into a wall face, front outwards, with the inside behind it.
Structure too small (…)	Build at least 5 wide, 5 high and 6 deep.
Structure too large or not closed near …	Close the wall at the position shown, or build smaller.
The turbine cross-section must be odd (…)	Make width and height odd.
Wrong block at … (expected: Rotor Shaft)	The centre line of the inside must be Rotor Shaft.
Wrong block at … (expected: Air, Compressor Blade, Combustion Liner, Rotor Blade, Generator Coil)	Only these blocks around the shaft.
Wrong block at … (expected: Gas Turbine Casing)	Only Gas Turbine Casing on edges and corners.
Blades and coils in the same slice near …	A slice holds parts of two stages; keep one stage per slice.
Stages out of order near … (compressor, combustion, turbine, generator)	Order the slices from the front: compressor, liners, rotor blades, coils.
Missing parts: … ×1	Every stage needs at least one block.
Port not allowed here: …	Only the Gas Input Port, Energy Output Ports and Heat Ports work.
Second controller at …	Remove the other controller.

Building the parts

	Redstone Dust
			→ Gas Turbine Controller

			→ Gas Turbine Casing

			→ Compressor Blade

	Blaze Rod
Blaze Rod	Blast Furnace	Blaze Rod	→ Combustion Liner
	Blaze Rod

Rotor Shaft, Rotor Blade and Generator Coil are the same as in the Steam Turbine.

When you break the controller, fuel, oxygen, energy and the rotor's speed are lost.

In the world

While formed, the shaft and both kinds of blades are hidden and a rotor is drawn that turns at the real speed. Flames burn behind the glass with the fuel flow, and exhaust rises from the roof when no Heat Port takes it.