Method and device for determining combustion noise parameters
A method and a device for determining combustion noise parameters, comprising acquiring a cylinder pressure sequence which comprises cylinder pressures corresponding to different crank angles φ and corresponding moments t φ ; calculating a first parameter sequence according to the cylinder pressure sequence, wherein the first parameter sequence is a parameter sequence in a time domain, and the first parameter sequence comprises one or more of a top surface cylinder force sequence, a top surface cylinder force rise rate sequence, a side surface cylinder force sequence and a side surface cylinder force rise rate sequence; and determining a target parameter for representing combustion noise in the cylinder according to the first parameter sequence.
1. A method for determining combustion noise parameters, characterized in that said method comprises:
acquiring a cylinder pressure sequence, wherein said cylinder pressure sequence comprises cylinder pressures corresponding to different crank angles φ and corresponding moments t φ ;
calculating a first parameter sequence according to said cylinder pressure sequence, wherein said first parameter sequence is a parameter sequence in a time domain, and said first parameter sequence comprises one or more of a top surface cylinder force sequence, a top surface cylinder force rise rate sequence, a side surface cylinder force sequence and a side surface cylinder force rise rate sequence;
wherein the top surface cylinder force in said top surface cylinder force sequence is F top =P c ·S top , the top surface cylinder force rise rate in said top surface cylinder force rise rate sequence is
F
.
top
=
d
F
t
o
p
d
φ
,
the side surface cylinder force in said side surface cylinder force sequence is F side =P c ·S side , the side surface cylinder force rise rate in said side surface cylinder force rise rate sequence is
F
.
s
i
d
e
=
d
F
side
d
φ
;
S top is an equivalent area of a cylinder top surface and S side is an equivalent area of a cylinder side surface; and
determining a target parameter for representing combustion noise in a cylinder according to said first parameter sequence.
2. The method according to claim 1 , characterized in that determining the target parameter for representing combustion noise in the cylinder according to said first parameter sequence comprises:
calculating a second parameter sequence corresponding to said first parameter sequence in a frequency domain; and
determining the target parameter for representing combustion noise in the cylinder according to said second parameter sequence.
3. The method according to claim 2 , characterized in that determining the target parameter for representing combustion noise in the cylinder according to said second parameter sequence comprises:
obtaining a corresponding third parameter sequence according to said second parameter sequence;
performing frequency weighting on said third parameter sequence to determine a target parameter for representing combustion noise in a cylinder;
wherein if said first parameter sequence comprises a top surface cylinder force sequence and/or a side surface cylinder force sequence, said third parameter sequence obtained by using
L
F
=
10
lg
(
F
′2
F
0
2
)
comprises a corresponding top surface cylinder force level sequence and/or a side surface cylinder force level sequence, said target parameter comprises a corresponding top surface cylinder force value L F top ′ and/or a side surface cylinder force value L F side ′, and F 0 is a reference force;
if said first parameter sequence comprises a top surface cylinder force rise rate sequence and/or a side surface cylinder force rise rate sequence, said third parameter sequence obtained by using
L
F
.
=
10
lg
(
F
.
′2
F
.
0
2
)
comprises a corresponding top surface cylinder force rise rate sequence and/or a side surface cylinder force rise rate sequence, and said target parameter comprises a corresponding top surface cylinder force rise rate value L {dot over (F)} top ′ and/or a side surface cylinder force rise rate value L {dot over (F)} side ′, and {dot over (F)} 0 is a reference force rise rate.
4. The method according to claim 1 , characterized in that acquiring the cylinder pressure sequence comprises:
acquiring a first cylinder pressure sequence according to a target crank angle interval;
determining said cylinder pressure sequence according to the relationship between the crank angle and the corresponding moment;
or,
acquiring a second cylinder pressure sequence according to a target time interval;
determining said cylinder pressure sequence according to the relationship between said crank angle and the corresponding moment.
5. The method of claim 4 , characterized by further comprising:
setting the position of the crankshaft when the highest cylinder pressure is reached for the first time in the cylinder as the position of the crank angle φ=0°, for the process of acquiring said first cylinder pressure sequence or said second cylinder pressure sequence.
6. A device for determining combustion noise parameters, characterized in that the device comprises:
an acquisition unit configured to acquire a cylinder pressure sequence including cylinder pressures P c corresponding to different crank angles φ and corresponding moments t φ ;
a calculation unit configured to calculate a first parameter sequence according to the cylinder pressure sequence, wherein said first parameter sequence is a parameter sequence in a time domain, and said first parameter sequence comprises one or more of a top surface cylinder force sequence, a top surface cylinder force rise rate sequence, a side surface cylinder force sequence and a side surface cylinder force rise rate sequence;
wherein the top surface cylinder force in said top surface cylinder force sequence is F top =P c ·S top , the top surface cylinder force rise rate in said top surface cylinder force rise rate sequence is
F
.
top
=
d
F
t
o
p
d
φ
,
the side surface cylinder force in said side surface cylinder force sequence is F side =P c ·S side , and the side surface cylinder force rise rate in said side surface cylinder force rise rate sequence is
F
.
s
i
d
e
=
d
F
side
d
φ
;
S top is the equivalent area of the cylinder top surface and S side is the equivalent area of the cylinder side surface;
a determination unit configured to determine a target parameter for representing combustion noise in a cylinder according to the first parameter sequence.
7. The device according to claim 6 , characterized in that the determining unit is specifically configured to:
calculate a second parameter sequence corresponding to said first parameter sequence in a frequency domain;
determine a target parameter for representing combustion noise in the cylinder according to the second parameter sequence.
8. The device according to claim 7 , characterized in that said determining unit is further specifically configured to:
obtain a corresponding third parameter sequence according to said second parameter sequence;
perform frequency weighting on said third parameter sequence to determine a target parameter for representing combustion noise in a cylinder;
wherein if said first parameter sequence comprises a top surface cylinder force sequence and/or a side surface cylinder force sequence, said third parameter sequence obtained by using
L
F
=
10
lg
(
F
′2
F
0
2
)
comprises a corresponding top surface cylinder force sequence and/or a side surface cylinder force sequence, said target parameter comprises a corresponding top surface cylinder force value L F top ′ and/or a side surface cylinder force value L F side ′, and F 0 is a reference force;
if said first parameter sequence comprises a top surface cylinder force rise rate sequence and/or a side surface cylinder force rise rate sequence, said third parameter sequence obtained by using
L
F
.
=
10
lg
(
F
.
′2
F
.
0
2
)
comprises a corresponding top surface cylinder force rise rate sequence and/or a side surface cylinder force rise rate sequence, and said target parameter comprises a corresponding top surface cylinder force rise rate value L {dot over (F)} top ′ and/or a side surface cylinder force rise rate value L {dot over (F)} top ′, wherein {dot over (F)} 0 is a reference force rise rate.
9. The device according to claim 6 , characterized in that said acquisition unit is specifically configured to:
acquire a first cylinder pressure sequence according to a target crank angle interval;
determine said cylinder pressure sequence according to the relationship between the crank angle and the corresponding moment;
or,
acquire a second cylinder pressure sequence according to a target time interval;
determine said cylinder pressure sequence according to the relationship between said crank angle and the corresponding moment.
10. The device according to claim 9 , characterized in that the acquisition unit is specifically configured to:
set the position of the crankshaft when the highest cylinder pressure is reached for the first time in the cylinder as the position of the crank angle φ=0°, for the process of acquiring said first cylinder pressure sequence or said second cylinder pressure sequence.