From years to a week: China unveils superfast software for hypersonic weapon design
China’s new software simulates scramjet physics in one week versus years, marking high-fidelity leap in hypersonic engine research
Chinese scientists have developed revolutionary software capable of fully simulating the extreme physics of supersonic fuel combustion in just one week.
Previously, the same task could take a supercomputer years to complete, they said.
It modelled its internal dynamics across hundreds of millions of computational cells – more than 20 times the resolution typical of current global research.
Despite the staggering complexity, the full simulation was completed in only seven days.
This simulation technology has provided critical support for the model design of a classified national project, according to a report on the website of the Institute of Mechanics in January.
Generally speaking, air-breathing hypersonic cruise missiles use scramjet technology to fly with power throughout their journey. Compared with boost-glide missiles, they are smaller, faster and harder to intercept.
The United States began researching air-breathing hypersonic technology as early as the 1950s but has struggled to make it work.
For hypersonic flight in near space – namely anything that travels at Mach 5 or faster – scramjets are more efficient and reusable than rocket motors or turbojet engines. The engines work by compressing incoming air through shock waves created at the intake.
However, at extreme speeds, the intense heat and pressure physically alter the air itself, causing molecules to vibrate, break apart or become ionised.
These changes, collectively known as thermal and chemical non-equilibrium effects, can disrupt compression, ignition and thrust.
Much of the research over the past half-century has assumed the incoming airflow is in an equilibrium state, a simplification that can lead to discrepancies between computational results and experimental data. It can even cause inaccuracies in predicting ignition delays.
While the type of fuel – hydrogen versus hydrocarbons – is known to significantly influence these non-equilibrium effects, research on hydrocarbon fuels like ethylene under such conditions has been scarce, primarily because of the high computational cost of modelling complex chemical reactions.
To capture the intricate microscale phenomena, Yao’s team developed a thermochemical non-equilibrium Dynamic Zone Flamelet Model (DZFM) combined with the Zonal Non-equilibrium Model (ZNM).
Their findings were published in the March issue of the journal Combustion and Flame.
For validation, the team ran a massive simulation of the HyShot II engine, a scramjet flight experiment, splitting its interior into 221 million individual cells.
Each cell’s temperature, pressure, velocity and chemical reactions were precisely calculated. This level of detail represented a major advance from the fewer than 10 million cells typically used in global research.
The results were astounding. A simulation of this complexity would normally take years to complete. The new model finished it in just 168 hours, or one week.
The findings have immediate, tangible consequences for missile design. The study found that, under real non-equilibrium conditions, both combustion efficiency and net thrust were lower. Traditional equilibrium assumptions may overestimate engine performance.
In one test case using hydrogen fuel, non-equilibrium conditions caused efficiency to drop by 8.9 per cent and thrust by 21.6 per cent.
By identifying where older models were too optimistic, the software allows engineers to refine fuel injection, combustion chamber geometry and cooling systems.
This ultimately could lead to engines that are not only faster but also viable for reliable powered flight.
Controversy haunts likely death of China’s hypersonic weapons expert Fang Daining
The distinguished academic continued working after he was disgraced by a kissing scandal but rarely appeared in public
The South China Morning Post could not confirm the online claims.
Some social media users said they were told not to photograph the obituary, a claim the SCMP was also unable to verify.
Fang, who studied super-strong materials for spacecraft and advanced engines at Beijing Institute of Technology (BIT), a key defence research university, “died of illness on February 27”, the obituary said.
“Fang’s passing is a major loss to China’s mechanics community, the field of advanced materials and structures, and higher education. We mourn his death with deep sorrow.”
