“Zilch” instead of explosion

They are being developed and tested by specialists of two Moscow academic institutes – Institute of Thermal Physics of Extreme Conditions (United Institute of High Temperatures, Russian Academy of Sciences) and the Institute of Structural Macrokinetics and Materials Science (ISMAN). By clarifying the mechanism of processes taking place in the course of gas combustion, they are learning to control these processes. The findings are extremely promising.

The most important phase of the investigation has become the ISMAN development of the chain-thermal explosion theory. The theory is based on the prerequisite that chain processes in gas-phase combustion play a determinative role not only at a low pressure but at the atmospheric pressure and a higher one. This theory allowed to find inhibitors, which break off chain avalanche, and therefore, in the long run, reduce explosive power. Such an inhibitor turned out to be the mixture of burning gases – propane, butane and propylene – taken at a defined proportion.

To verify the theory in practice, a special blasting chamber is at the disposal of the researchers. The chamber was made in Severodvinsk by specialists who design submarines, of special ultrastrong armored steel, this ideally spherical chamber is capable of standing an explosion of a ton of trinitrotoluene. No wonder – given the internal diameter of 12 meters, the deviations from this value make no more than 10 millimeters at any point of its surface! It is in this chamber equipped with all necessary facilities that the researchers are making experiments. They do not simply let in a large quantity of hydrogen and air and explode it. They use a special reactor – a cone with piezoelectric sensors and some other measurement instrumentation placed along its surface and at the vertex. It is because the drastic reduction of reaction space (at the vertex of cone) enables to “concentrate” energy of explosion and to achieve maximum high pressure – up to 1,000 atmospheres.

It has turned out that introduction into the hydrogen/air combustible mixture of only 1.5 percent of inhibitory mixture allows to reduce the pressure in the cone by 20 times, and sometimes by 30 times, i.e., actually to suppress the explosion! Instead of blowing up, the dangerous mixture simply burns down – and there is zilch in place of explosion!

Having made sure that it is possible in principle to suppress the explosion chemically, the researchers continue their investigations. They examine reaction mechanisms in more detail, look for new inhibitors, try to reduce their quantity – this is important both in terms of ecological and economic considerations. Besides, the authors have now seriously passed on to search of inhibitors for the air/methane mixtures – the need for such investigations is evident: mines and houses with gas-stoves, alas, continue to blow up.

To make the researchers’ effort more effective, a special building has been erected this year around the chamber, so that the researchers did not have to stiffen on their “barrel” (as they call the blasting chamber among themselves) working during a winter snowstorm in freezing wind.