159: Chapter 159 Plasma Discharge Experiments

Early the next morning, before dawn on Science Island, the main experimental building housing the east device was already brightly lit.

Chen Youhua arrived at the Main Control Hall right on time.

The place seemed even more crowded today than in previous days. Almost every workstation was occupied, with everyone intently staring at the screens in front of them, whispering as they performed final parameter confirmations and system status checks.

The huge circular main screen no longer displayed complex data streams, but was clearly divided into several zones.

They respectively displayed the final status of each system in the device, the main target parameters for this experiment, and a reserved window for core plasma diagnostic data.

Academician Yang Zhenyu was already standing by the command console in the center of the hall, engaged in final communication with several subsystem leads.

He was wearing a slightly formal shirt today, his brows slightly furrowed.

Seeing Chen Youhua enter, he nodded, signaling him to come over.

"Youhua, you're here. How are you feeling?" Academician Yang's voice was lower than usual.

"Ready." Chen Youhua answered concisely, standing in an open position beside Academician Yang.

Engineer Yang quickly handed him a headset to facilitate listening to reports from various locations.

"Attention all units, we are now two hours before the experiment."

Academician Yang spoke into the microphone, his voice echoing throughout the hall via the amplification system.

"According to the final experimental plan, perform one last full system self-check and status confirmation. Report any abnormalities immediately."

With the order given, the atmosphere in the Main Control Hall became even heavier.

Only the clicking of keyboards, the occasional internal communication prompt, and the very low voices of Researchers giving status reports could be heard.

"Vacuum team reporting, the base vacuum of the vacuum chamber meets the standard, residual gas analysis is normal."

"Cryogenic system reporting, superconducting magnets have fully entered the superconducting state, magnetic field strength is stable."

"Power system reporting, toroidal field and poloidal field power supplies are ready, capacitor energy storage is sufficient."

"Heating system reporting, neutral beam injector preheating is complete, radio frequency system frequency is locked."

"Diagnostic system reporting, all diagnostic equipment calibration is normal, data acquisition sequence is loaded."

...

One calm report after another came in, indicating that this massive system was step-by-step entering the predetermined experimental state.

Chen Youhua's gaze quickly scanned the key parameters on the main screen, comparing them with the optimization targets and safety thresholds stored in his mind.

Everything seemed to be on the scheduled track.

Time ticked by.

When there were thirty minutes left until the scheduled start time, Academician Yang picked up the microphone again.

"Experiment leads, perform a final confirmation of the experimental sequence."

Each subsystem lead confirmed one by one that the command sequence was correct.

Ten minutes left.

You could hear a pin drop in the hall.

Chen Youhua could feel his heartbeat accelerating slightly; this was an instinctive reaction when facing a major challenge, but his breathing remained steady, and he was still calm.

Academician Yang took a deep breath and scanned the entire room.

He spoke into the microphone, issuing the command in a steady and powerful voice.

"I hereby order, the nth plasma discharge experiment of the east device, start now. Execute according to the predetermined program."

Once the order was given, it was as if an invisible switch had been pressed.

On the huge screen in the Main Control Hall, numbers representing energy began to pulse, and complex curves began to be drawn.

"Start injecting working gas..."

A set of pressure parameters on the screen began to rise slowly.

"Toroidal field magnetic field established and stable..."

"Poloidal field coils energized, forming the initial magnetic field configuration..."

"Ohmic heating started, generating initial plasma current..."

A waveform diagram in the center of the main screen showed a bright curve suddenly rising, marking the successful generation of the initial plasma inside the vacuum chamber.

"Plasma breakdown successful! Current rising steadily!"

The monitoring Researcher reported, his voice tinged with suppressed excitement.

Chen Youhua stared intently at the curves representing plasma current and density, which were steadily climbing along the predetermined trajectory.

"Neutral beam injection started!"

"Ion cyclotron resonance heating started!"

"Electron cyclotron resonance heating started!"

With each command, more energy was injected into the invisible, high-temperature plasma constrained within the magnetic field.

The curves representing plasma temperature and density began to climb with a steeper slope.

The hall was filled only with the sound of Researchers at their stations staring at screens and occasionally reporting key data.

"Plasma core electron temperature has exceeded 30 million degrees!"

"Density has reached 80% of the target value!"

"Plasma current is stable!"

"Signs of H-mode transition observed!"

Good news kept coming, but everyone's heart was still hanging in the balance.

The most critical steady-state high-confinement operation phase was approaching, which was also the phase most prone to various instabilities.

Chen Youhua's gaze was like the most precise radar, quickly switching between several small windows representing key parameters such as edge turbulence, radiation power, and divertor heat load.

His brain worked at high speed, performing millisecond-level comparisons between real-time data and his model predictions.

Suddenly, the voice of the Researcher in charge of boundary diagnostics rose by a notch.

"ELM precursor activity detected at the boundary! The frequency is increasing!"

Almost simultaneously, the curve representing the divertor target heat load began to show violent jagged jitter, and the peak value was continuously spiking!

"ELM burst! Heat load peak is approaching the warning threshold!"

The voice of the engineer from the divertor team became tense.

Everyone's heart was in their throat.

Large ELMs are a byproduct of the high-confinement mode, but the huge energy they release instantaneously is a great test for divertor materials.

Academician Yang's expression was grave, but he did not immediately order intervention.

Because this was a new model, he did not know what would happen after it started running.

He had predicted several possible situations in advance; at this moment, he was thinking about which situation this belonged to and how to deal with it.

And at this critical moment.

Chen Youhua spoke extremely fast but clearly.

"The peak duration is within the predicted range, and the spatial distribution matches the simulation. No manual intervention needed for now, observe its natural decay, pay attention to the next cycle!"

His calm judgment gave the command center confidence.

Sure enough, after a dozen milliseconds, the violent heat load peak began to decay rapidly.

The device successfully withstood this shock.

However, the challenge was not over.

In the subsequent attempt to push plasma parameters to higher target values, the Researcher in charge of radiation monitoring reported.

"Core radiation rate is abnormally increasing! Impurity accumulation might have occurred!"

Impurity accumulation would cool the plasma, leading to performance degradation or even termination of the experiment.

"It might be that the first-wall material has been sputtered in." Someone whispered.

Chen Youhua immediately turned his gaze to the relevant spectral diagnostic data, quickly analyzing the impurity composition and radiation distribution.

"It's not the first-wall material," he quickly refuted.

"Look at the characteristic spectral line intensities of carbon and oxygen; it's more like residual background gas in the vacuum chamber being ionized. Try slightly increasing the RF heating power in the edge region and use shear flow to sweep the boundary."

The heating system immediately executed the fine-tuning.

A few minutes later, the upward trend of the core radiation rate was contained and began to slowly decline.

"It's effective!" Someone couldn't help but whisper.

Sudden small issues kept appearing, only to be resolved one by one through the close cooperation of the entire team and the precise judgments occasionally provided by Chen Youhua.

The experimental time passed bit by bit in a thrilling manner.

Finally, the predetermined long-pulse high-confinement operation time target was achieved!

"Start the decay of the plasma current flat-top segment!"

"Gradually reduce heating power according to the program!"

"Safe soft termination of plasma!"

When the curve representing plasma current steadily fell back to zero and all data curves on the main screen calmed down, the Main Control Hall fell into a brief silence.

Immediately, not knowing who started it, enthusiastic applause erupted like a tidal wave, quickly sweeping across the entire hall!

Researchers stood up from their seats one after another, their faces filled with tired but incomparably excited smiles, high-fiving and hugging each other!

Success!

A near-perfect long-pulse high-confinement operation experiment!

Academician Yang Zhenyu let out a long sigh of relief, a look of relief and gratification finally appearing on his tense face, and the wrinkles at the corners of his eyes smoothing out.

He patted Chen Youhua's shoulder hard.

Chen Youhua also smiled, a weight lifted off his heart.

He looked around at these cheering scientific Researchers and truly felt the immense sense of achievement and satisfaction brought by the verification of theoretical models in engineering practice.

As the applause subsided slightly, Academician Yang picked up the microphone, his voice slightly hoarse from excitement but full of strength.

"I announce that the nth plasma discharge experiment of the east device is a complete success! Thank you all for your hard work and excellent performance! Everyone has worked hard!"

Even louder cheers and applause rang out again.

Academician Yang put down the microphone, turned to Chen Youhua, and held his hand tightly.

"Youhua, thank you so much, your model and those optimization suggestions played a key role in this experiment! Especially the pre-judgment of ELM and impurity behavior, which helped us avoid several potential interruptions!"

Chen Youhua was taken aback; he hadn't actually pre-judged them; every judgment he made was based on real-time reasoning through various data.

Although Academician Yang might have misunderstood something, Chen Youhua still replied humbly.

"This is the result of everyone's joint efforts."

"The experimental data is very valuable; we need to analyze it in detail next to see which parts fully met expectations and where there are deviations; this can provide a more precise direction for the next step of optimization."

"Right! Data analysis starts immediately!" Academician Yang nodded heavily.

"Let's go, Youhua, let's go see the preliminary summary data! I can't wait to see how beautifully we ran this time!"

In the Main Control Hall, the Researchers, after the excitement, had already quickly returned to their seats and begun intense post-experiment data processing and analysis.

For them, the success of the experiment was not the end, but the starting point for another more in-depth study.