Case Study: Regulation of Noise Produced by a Rotary-screw
Propulsion Unit in an All-terrain Vehicle
Umar Vahidov, Alexander Belyaev, Vladimir Makarov
a
, Dmitriy Mokerov and Yuri Molev
Nizhny Novgorod State Technical University n.a. R.E. Alekseev, Minin St., 24, Nizhny Novgorod, Russian Federation
Keywords: Rotary-screw Propulsion Unit, Ice, Interaction, Noise Level.
Abstract: The study presents methods developed to calculate permissible level of acoustic radiation produced by a
rotary-screw propulsion unit on ice. The study is based on the papers of the researchers who studied acoustic
waves generated by construction and road vehicles. The authors of the study applied the aforementioned
theories to the case of interaction between a rotary-screw propulsion unit and ice. The paper provides general
measuring methods and evaluates how every type of interaction between propulsion unit components and ice
affects overall level of generated acoustic pressure. The results and conclusions obtained during the research
can be used to help manufacturers select the parameters of the rotary-screw propulsion unit which contribute
to reduction of noise inside the cabin of an all-terrain vehicle.
1 INTRODUCTION
One way to increase population mobility and
transport accessibility in less-populated regions is to
develop all-terrain vehicles. However, there is one
issue that remains unresolved, and challenges the
development of such vehicles: poor ride comfort due
to high noise and vibration levels [Shashurin, 2010].
Multiple research papers studying technical
condition of all-terrain vehicles have established that
acoustic impact on vehicle drivers considerably
exceeds permissible values reducing efficiency of all-
terrain vehicles and affecting the occupants [SanPiN
2.2.4.3359-16, SN 2.2.4/2.1.8.562-96, SP
51.13330.2011].
2 THEORETICAL RESEARCH
Noise generated by all-terrain vehicles has three main
sources: engine and transmission, vibration
fluctuations caused by uneven road surface, and a
rotary-screw propulsion unit. Design of most all-
terrain vehicles is currently based on wheeled
vehicles permitted to participate in road traffic,
suggesting that cabin, engine, transmission units and
assemblies comply with enforceable requirements to
a
https://orcid.org/0000-0002-4423-5042
Figure 1: Noise level measured in the cabin of snow and
swamp-going vehicle “Uzola” manufactured by LLC “All-
Terrain Vehicles Plant” in Zavolzhye. [https://zvm-nn.ru].
548
Vahidov, U., Belyaev, A., Makarov, V., Mokerov, D. and Molev, Y.
Case Study: Regulation of Noise Produced by a Rotary-screw Propulsion Unit in an All-terrain Vehicle.
DOI: 10.5220/0009570605480551
In Proceedings of the 6th International Conference on Vehicle Technology and Intelligent Transport Systems (VEHITS 2020), pages 548-551
ISBN: 978-989-758-419-0
Copyright
c
 2020 by SCITEPRESS – Science and Technology Publications, Lda. All rights reserved

Figure 2: Noise level measured in the cabin of a multi-
functional rescue vehicle with a rotary-screw propulsion
unit produced by Research and Education Centre
“Transport”, Nizhny Novgorod State Technical University
n.a. R.E. Alekseev.
noise level on the road. Also, perfectly smooth ice
rules out noise caused by deformation, and bending
of body and rotary-screw propulsion unit components
[Nikitin, 2004, Abramova, 2018, Erasov, et al. 2019].
Considering the abovementioned, overall level of
noise generated by the rotary-screw propulsion unit in
an all-terrain vehicle cabin can be calculated from the
following overall noise level equation [SN
2.2.4/2.1.8.562-96]:
)
1,0
10
0,1
lg(1010
n
1i
1,0
10 lg10
K P
i
LL
L
L
L
+=

=
=


(1)
where L
K
is overall noise level in the all-terrain
vehicle cabin with rotary-screw propulsion unit
switched off, and LP is the sought-for noise level
produced by the rotary-screw propulsion unit. From
which we obtain the following:






−
+=−

)(1,0
101lg10
PK
LL
K
LL
(2)
or:






−
=−
−

)(1,0
101
)(1,0
10
КРK
LLLL
)LL(,)
КР
)LL(,
K
−=−
−

10110lg(
10
K
)LL(,
Р
L)L
K
+−=
−

11010lg(
10
(3)
In his paper “Measurement of noise in the cabins
of construction and road vehicles” [Shashurin, 2010],
A.E. Shashurin states that equation for cabin noise
level generated by a linear source of acoustic
vibrations, i.e. by a rotary-screw propulsion unit, can
be sought from the following equation:
,2lg10)1lg(10
0
lg10lg10
2
lg10
++−+
++−+
+−=
K
r
r
A
S
r
L
arctg
Р
L
D
L

(4)
where L/2r – ratio of the noise source length to the
distance from the source to the cabin (for rotary-
screw propulsion units, this ratio equals to 3),  -
diffuse field approximation factor, r
0
– distance from
the cabin floor to the ground surface (r/r
0
ratio for
rotary-screw propulsion unit vehicles is 1, because
noise is generated at the point where rotary-screw
propulsion unit has contact with the ground surface)
S – total area of the all-terrain vehicle cabin, which
can vary from 10 to 50 square meters depending on
the design; A – equivalent sound absorption surface
of the cabin, which equals to the total area of the cabin
multiplied by sound absorption factor  (0,3 [11] for
low-frequency acoustic vibrations produced by a
propulsion unit),  – cabin sound insulation factor,
when critical sound insulation frequency for the walls
(f
gr
), equal to 100-200 Hz, is lower than the sound
frequency f (up to 500Hz) calculated from the
following equation:
dB
gr
f
ffM
3015325,0lg
136
500
lg5
0,1*2,1
01,0*1000*500*14,3
lg20
3lglg5
r
lg20
−=++
++=
=+++








= 


(5)
where М is a factor equal to the ratio of the acoustic
blanket weight (blanket density multiplied by its
thickness) to the air weight between the driver and the
cabin walls (air density multiplied by the distance
from the driver to the cabin wall), and  - loss factor
equal to 0,25 [Shashurin, 2010];
According to [Shashurin, 2010] 10lg(S/A) ratio
varies from 20 to 12dB, 10lg(1-
К
) ratio from 0 to 4
dB varies from 20 to 12dB. Therefore, maximum
sound level generated by a propulsion unit in the
Case Study: Regulation of Noise Produced by a Rotary-screw Propulsion Unit in an All-terrain Vehicle
549

ground surface contact area shall be calculated
according to the following formula:
,L)L
K
)LL(,
D
K
1911010lg(
10
++−=
−

(6)
Minimum sound level shall be as follows:
K
)LL(,
Р
L)L
K
+−=
−

11010lg(
10
(7)
The 19 dB difference indicates that current cabins
reduce sound level generated by propulsions units of
all-terrain vehicles approximately by 19 dB.
Solution of these equations is presented in Figure
3.
Figure 3: Relationship between the maximum permissible
sound level produced by a propulsion unit and the sound
level inside the all-terrain vehicle generated w/o the
propulsion unit with no sound insulation of the cabin (1)
and with standard sound insulation (2).
3 EXPERIMENTAL RESEARCH
Research conducted on various propulsion units of
all-terrain vehicles shows that current design of the
propulsion units does not always keep the generated
sound within the acceptable limits.
4 CONCLUSIONS
The results show that propulsion units with acoustic
radiation under 70dB have almost no effect on the
sound level in the cabin. Propulsion units with
acoustic radiation of 90-100dB produce the noise
which considerably influences acoustic comfort in the
cabin, and those with radiation level over 105 dB
become the only source of noise around the driver.
Figure 4: Sound level generated by a rotary-screw
propulsion unit on the concrete.
Figure 5: Sound level produced by a rotary-screw
propulsion unit on marsh.
Figure 6: Sound level generated by a rotary-screw
propulsion unit on water and sand.
Since the technical regulations in force [GOST
23941-79, GOST 27408-87, GOST Р 51401-99]
stipulate a 80 dB limit for the permissible noise level
in the cabin. We can use the obtained data to develop
VEHITS 2020 - 6th International Conference on Vehicle Technology and Intelligent Transport Systems
550

requirements to a rotary-screw propulsion unit
installed in various types of vehicles.
ACKNOWLEDGEMENTS
This study was conducted in continuation of the
research conducted in the "Nizhny Novgorod
scientific and practical school of transport snow" in
the framework of cooperation between the Nizhny
Novgorod state technical University. R. E. Alekseeva
and LLC All-Terrain Vehicles Plant.
REFERENCES
Abramova, E., Mashorin, G., Molev, Y. and Sogin, A.,
2018 The simulations of helical blade interaction with
ice. MATEC Web of Conferences 245, 17002
GOST 23941-79 Noise. Methods for determination of noise
characteristics. General requirements.
GOST 27408-87 Methods for statistical processing of data
in determination and control of machine emitted noise
level.
GOST Р 51401-99 Noise of machines. Determination of
sound power levels of noise sources using sound
pressure. Engineering method in an essentially free
field over a reflecting plane.
Erasov, I., Kuklina, I., Mokerov, D. and Molev, Yu, 2019.
Simulation of noise generated by a rotary-screw mover
as a result of friction. IOP: Conference Series Earth and
Environmental Science 695, 012027.
Lipin, A., Molev, Y., Mokerov, D., Strizhak, A. and
Khudyakov, V., 2019 Ways of decreasing noise impact
on operator by changing rotary-screw propulsion units
natural frequency of vibration. IOP: Journal of
Physics: Conference Series 1177: 012040
Nikitin, S.A., 2004 Snowblower with optimized vibration
and sound characteristics. PhD thesis. Voronezh, 159 p.
SanPiN 2.2.4.3359-16 "Sanitary-epidemiological
requirements to physical factors in the workplaces"
SN 2.2.4/2.1.8.562-96 "Noise at Workplaces, in Residential
and Public Spaces, and in Areas of Residential
Development"
SP 51.13330.2011 Sound Protection. Updated SNiP version
dd. 23-03-2003
Shashurin, A.E., 2010. Case study: Interior noise reduction
with sound-insulating cabins in construction vehicles:
PhD thesis. Baltic State Technical University
"Voenmeh" D.F. Ustinov. St. Petersburg, 178 p.
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