Formalization of a methodology for measuring of the noise from small sports airports.
Badida, Miroslav ; Herczner, Peter ; Konkoly, Jozef 等
Abstract: The phenomenon of aircraft noise is not only cover of a
major international airport, where is the traffic dense and intense as
the transport of cargo and passenger aircraft, but also a problem of
small sport airports that have less traffic overall. The proposed
methodology has been developed for small sport airport and has been
successfully tested on a small airport on sports aeroelub airport
Kamenica nad Cirochou. Key words: environment, noise, small sport
airports, air traffic
1. INTRODUCTION
This methodology will try to work comprehensively mapping all the
essential elements that affect the calculation of the level of aircraft
noise contours and noising from air traffic. Requirements for the
calculation of aircraft noise can vary greatly depending on the nature
of the airport, weather conditions, airport-type and other factors.
Three separate parts of assessing aircraft noise process are shown in
Fig. 1.
[FIGURE 1 OMITTED]
The proposed methodology implements all the necessary tools to
calculate the noise level, which is emitted into the environment in the
vicinity of airports.
2. DESCRIPTION OF AIR TRACK
Location of aircraft around an airport is defined fixed network
coordination system. X and Y coordinates are designated as ground
coordination system of coordinates and altitude as coordinate the
opening climb of the aircraft, after reaching the point of [M.sub.c], as
shown in Fig. 2.
[FIGURE 2 OMITTED]
[FIGURE 3 OMITTED]
Coordinate system starting position is always at the measurement
point Mc. The measurement point is shown in Fig. 3. N-distance of the
aircraft's position will vary depending on the speed of the
aircraft. The size of the grid and the network itself is determined
individually, always in direct contact with the aircraft type, aircraft
speed and the individual needs of the observer. According to the results
obtained, which are measured from the observation point is calculated in
the simulation time during the stress level while passing aircraft.
3. CALCULATION OF AIRCRAFT NOISE
3.1 Basic calculation When measurements are generally used for
spectral filter A weighting filter, which is close to approaching the
sensitivity of the human ear and the time constant introduced
"SLOW" air noise. Sound pressure is time-variable function
that creates the output variable for the time value of the load. The
resulting calculation of sound pressure level as a time variable
function is then defined as:
[L.sub.A](t)= 10 x log p[(t).sup.2]/[p.sup.2.sub.0]. (1)
Total measurement is always dependent on many factors. These
factors alone have an impact on the measured values at the measurement
point and then to calculate the actual noise and its impact on the
environment. One factor which is introduced is the mean noise or
equivalent noise level [L.sub.eq]. Equivalent noise level is the energy
average sound level spriememenej during the measurement interval. It is
defined as sound pressure level of continuous steady sound that within a
time interval measurement t=[t.sub.2]-[t.sub.1], has the same mean
square sound pressure as a reference sound, which varies over time. The
basis for the determination of measurement interval or the reference
time and land - the sound pressures [L.sub.A(t)]. The actual calculation
of equivalent sound level [L.sub.eq(t)] is then defined as:
[MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] (2)
3.2 Speed correction
Correction speed adjusts the speed of the aircraft itself. It is
used when the speed of a certain segment of take-off runway is
significantly different than the other segments, and thus significantly
changed the reference speed Vref, which are contained in the database
NPD. Around the track section is hereby set performance engine, so
engine power and speed of the aircraft.
[DELTA]V = 10 X log([V.sub.ref]/[V.sub.seg](resp. [V.sub.seg.kol]))
(3)
3.3 Correction of the tilt plane
Noise from air traffic is not only of themselves but the overall
engine noise from the flight itself. Very significant impact on the
noise of the airplane has a location, design and installation of engines
on the aircraft. The increase in noise occurs when the aircraft itself
is tilted and is significantly affected by the conduct of the process of
reflection, refraction and scattering effects of noise on hard surfaces
of take-off runway. The actual impact is then the uneven dispersion of
the sound environment around the airport. It is then necessary to
correct the slope of the aircraft itself. The actual calculation of the
correction will be performed by the calculation formula, which contains
the basic angles of inclination and length distance placing the engine
on the wing.
[MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] (4)
3.4 Total correction
Sedation after the summation of all of the corrections is then
calculated as the sum of all of the corrections in chapters 3.2 to 3.3.
[L.sub.korr] is then calculated according to:
[L.sub.korr] = [DELTA]V + [DELTA]I([epsilon]) (5)
3.5 The value of the load after correction L max
Load value is always evaluated after accounting adjustments. For
the actual calculation is used the equivalent sound level [L.sub.eq] if
it is then added the necessary corrections. The actual calculation will
be performed using the equation:
[L.sub.max = [L.sub.eq] (t) + [summation (i)] [L.sub.korr](6)
The total amount [L.sub.korr] examines all the disruptive effects
of different types of noise in the same buffer [L.sub.eq]. This variety
is introduced only for certain types of airports, always depending on
the type of airports, especially in civil and military and the nature of
the take-off runway and its individual segments.
4. PRACTICAL APPLICATION
The airport, where the measurements were carried out, is located
east of the city Humenne. It is a civilian sport airport, which is
incorporated into the network Aeroclub Slovakia. The airport is located
in greenfield areas noah of the village of Kamenica nad Cirochou.
The airport has two runways no. 07 take-off, and no. 25. These are
located north of the buildings around the hangar. 150 m. runways are
located in flat areas with no more inclination surface of the track
itself.
[FIGURE 4 OMITTED]
5. MEASUREMENT RESULTS
In different parts of the table zou can see the values for the
correction, if it was necessary to modify the resulting data on the
speed and tilt correction aircraft Tab. I.
The noise descriptors measured in the individual measuring points,
which were placed in the take-off runway is stated the following
conclusions:
--measurement of aircraft noise around the Aeroclub of Kamenica nad
Cirochou at the measuring points 1 to 4 is shown that there are not
exceeded immission values for determining values of environmental noise
at all measuring points in a set time interval,
--it is not necessary to determine the correction for the
acceleration of aircraft on take-off runway, because it did not reach
maximum speed defined for this type of aircraft,
--the need to establish correct tilt of the aircraft because the
aircraft has located the propulsion unit in front and not on the wings,
--noise, which was due to the surrounding environment, is the noise
from the remote village of Kamenica Cirochou. Noise from the building
reconstruction and traffic is negligible and has no impact on the
measured values of air traffic at the airport Aeroclub Kamenica nad
Cirochou,
--there is no need to introduce any measures to reduce noise
emitted from traffic at the airport Aeroclub Kamenica nad Cirochou.
We can assume that if the future does not change the flight
schedule, it stops at the Airport aircraft at a higher power has taken
place or reconstruction of the runway take-off from turf to asphalt, we
can assume that the noise will increase the burden of air transport and
the airport itself. We assume that the noise emissions from aircraft,
which are emitted into the environment, will increase the airport. The
type of aircrafts, which operated at the airport, it is a ZLIN and
Cessna engine, which rank among the older types of single aircraft. For
these aircraft we assume that the future will improve their motor units,
and in conjunction with the team likely will sound and the noise emitted
to the environment around the airport over Aeroclub Kamenica nad
Cirochou. This paper was created under the project KEGA no. 3/7426/09.
6. REFERENCES
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prostredie. Vienala, Kosice, 1998. ISBN 80-7099-335-9
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international conference Modern Technologies in
Manufacturing.--Cluj-Napoca: MTeM, 2009 P. 321-324.--ISBN 97379370704
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posudzovania akustrickej situacie v okoli zeleznicnych trati In:
Mechanical Engineering 2007: proceedings of abstracts: Bratislava,
November 2007, Bratislava: STU, 2007. ISBN 978-80-227-2768-6
Herczner, P.; Romanova, M.; Lumnitzer, E.: Analf, za metodiky NMBP
Route 96 a jej aplikscia pri rekondtrukcii krizovatky ciest 1. Triedy.
In: 9. Banskostiavnicke dni 2007-volen TU, 2007. ISBN 978-80-228-1786-8
Lumnitzer, E.; Badida, M.: The usage of dynamic visualisation by
industrial noise source analysis. In: Acta Mechanica Slovaca. Roc. 13,
c. 1 (2009), s. 20-24.--ISSN 1335-2393
Tab. 1. Summary results plus of the corrections
Measuring Measurement [L.sub.Asmax, [L.sub.Aeq, 2h] [DELTA]V
point time 2h] [dB] [dB]
[h] [dB]
1 9:00-11:00 97,6 67,4 --
2 9:00-11:00 88,2 59,3 --
3 9:00-11:00 91,5 65,6 --
4 9:00-11:00 88,3 59,3 --
Measuring [DELTA]I(epsilon] [L.sub.korr] [L.sub.Aeq, 2h, korr]
point [dB] [dB] [dB]
1 -- -- 67,4
2 -- -- 59,3
3 -- -- 65,6
4 -- -- 59,3
