Article 5 # 3'2023

© Volodymyr Fedorov, Candidate of Technical
Sciences (Ph.D.), ORCID: 0000-0002-1085-5112,
© Oleksii Korpach, Candidate of Technical Scienc-es (Ph.D.), ORCID: 0000-0002-2496-4395,
© Dmytro Yashchenko, Candidate of Technical
Sciences (Ph.D.), ORCID: 0000-0003-3674-0089,
© Volodymyr Bosenko, Candidate of Technical
Sciences (Ph.D.), e-mail: в,
ORCID: 0000-0003-2126-3902
National Transport University
DOI: 10.33868/0365-8392-2023-3-275-36-41

Abstract. Armored vehicles are widely used for combat operations, for which it is extremely important to be as inconspicuous as possible. There are different types of masking, one of which is reducing the level of external noise. For the Novator armored car, a highly effective muffler of the exhaust gases of the internal combustion engine was devel-oped. The Novator armored car has a pickup-type body, a gross weight of 9,000 kg and a Ford F8 turbodiesel engine with a power of 300 hp. The uniqueness of the developed muffler is that it seeks to return all the sound waves that entered it back to the intake pipe. This effect is achieved due to the specific structure of the silencer housing. The case is an ellipsoid of rotation.At the same time, the section of the intake pipe (the pipe that goes into the muffler) is placed in the first focus of the ellipsoid of rotation, and the sound waves propagate to the inner wall of the elliptical body, reflect from it, con-verge at the second focus, and then continue to move to the opposite wall, reflect from it, converge in the first focus and spread further back into the intake pipe. In the intake pipe, there is partial interference of the reflected sound waves when they meet the incoming waves, and the final absorption by the sound-absorbing material. At the same time, exhaust gas-es, bouncing off the walls of the muffler, leave the latter through the exhaust pipe.
At the same time, the exhaust pipe exits the ellipsoid of rotation coaxially with the intake pipe, which enters the pipe tel-escopically with a gap. Taking into account the directional diagram of sound energy radiation at the exit from the ex-haust pipe, a proposal was made to create a muffler not as a full ellipsoid of rotation, but in the form of a half ellipsoid of rotation. Such a solution will make the muffler significantly cheaper and much more compact, which is essential for a military vehicle.
Keywords: armored car, “novator”, masking, camouflage, silencer, ellipsoid of rotation, directional diagram, acoustic efficiency, sound waves, sound absorbing material.

1. Barracuda MCS Specifications. (2015). Retrieved from
2. “Novator” Specifications. (2019). Retrieved from
3. “Novator” Specifications. (2019) Retrieved from
4. Fedorov, V. V. (2010). Hlushnyk shumu. Silencer. Patent No. 89377, bulletin “Industrial Property” No. 2.