Researchers at Perm National Research Polytechnic University (PNRPU) have identified an optimal granular fuel blend for ramjet engines used in rockets and jet aircraft. This update was conveyed to socialbites.ca by the institution’s press service.
The ramjet design favors simplicity and a streamlined set of components. Its thrust comes from fuel combustion and the resulting jet exhaust. The platform comprises a diffuser, a combustion chamber, and a nozzle, complemented by auxiliary fuel delivery and ignition systems. Such engines find application on cruise missiles and unmanned aerial vehicles that operate at speeds between 2,400 and 6,100 kilometers per hour (roughly Mach 2 to Mach 5).
Polytechnic researchers conducted detailed calculations on fuel substances and their various mixtures, evaluating temperature, density, and mass fractions. To determine the most suitable fuel composition, scientists employed a specialized simulation to predict how these blends would perform under flight conditions at an altitude of around 30 kilometers.
As part of the study, experts selected widely used rocket fuel components (HMX, ammonium perchlorate, divinyl copolymer) and explored lesser-known yet promising additives with high thermal energy content (azepines) — measures of the energy released during fuel combustion per unit mass.
Granular fuel is not currently standard in ramjet configurations. However, Perm Polytechnic’s findings indicate that such an approach is feasible and effective when the fuel mixture is carefully optimized for performance.
Marketing the concept, Grigory Dotkin, a graduate student in the Department of Rocketry and Aerospace Engineering and Energy Systems at PNIPU, explained that granular fuel offers fluidity and the ability to regulate flow. Each granule combines an oxidizer particle with a fuel coating, a structure that is difficult to replicate with separate feed systems. In addition, mixing fuel components can reduce the required air intake for the afterburner, enabling ramjets to operate at higher altitudes and within thinner atmospheric layers.
(Citation: socialbites.ca, reporting from the institution’s press service)
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