(完整word版)物理性污染控制习题答案第二章.pdf
《(完整word版)物理性污染控制习题答案第二章.pdf》由会员分享,可在线阅读,更多相关《(完整word版)物理性污染控制习题答案第二章.pdf(10页珍藏版)》请在淘文阁 - 分享文档赚钱的网站上搜索。
1、1/10物理性污染控制习题答案第二章噪声污染及其控制1.什么是噪声?噪声对人的健康有什么危害?答:噪声是声的一种,是妨碍人们正常活动的声音;具有声波的一切特性;主要来源于固体、液体、气体的振动;产生噪声的物体或机械设备称为噪声源。噪声对人的健康危害有:引起耳聋、诱发疾病、影响生活、影响工作。2.真空中能否传播声波?为什么?答:声音不能在真空中传播,因为真空中不存在能够产生振动的弹性介质。3.可听声的频率范围为2020000Hz,试求出 500 Hz、5000 Hz、10000 Hz 的声波波长。解:,c=340m/s,3400.6815003400.068250003400.003431000
2、0cfmmm4.声压增大为原来的两倍时,声压级提高多少分贝?解:220lg,20lg20lg20lg 200020lg 26()pppeeeLLpppppLLLdBppp5.一声源放在刚性面上,若该声源向空间均匀辐射半球面波,计算该声源的指向性指数和指向性因数。解:22S4=2 DI=10lg10lg 23.01WS2SWSIrQQIr半全,半全6.在一台机器半球辐射面上的5 个测点,测得声压级如下表所示。计算第5 测点的指向性指数和指向性因数。测点1 2 3 4 5 声压级/dB 85 87 86 84 89 解:2/100.18.58.78.68.48.91110lg(10)10lg(10
3、10101010)86.6()510.110220.10.10.1(8986.6)010101.7420.1102010lg10lg1.742.4LnpiLdBpniLpLLIppppQILpppDIQ.7.已知某声源均匀辐射球面波,在距声源 4m处测得有效声压为 2Pa,空气密度 1.23/kg m。使计算测点处的声强、质点振动速度有效值和声功率。解:2222,000,20ppDVeeIDc DWIS WSp u Sp cu Se eeccS tpueAuueec233223229.8 10(/)1.2 3400224.9 10/1.2 3402220009.8 10441.97()peIW
4、 mcppupeeAAum secccWISW8.在半自由声场空间中离点声源2 m 处测得声压的平均值为88 dB,(1)求其声功率级和声功率;(2)求距声源 5m 处的声压级。解:(1)按球面波考虑0.1120.1 1051.5020lg1120lg118820lg 211105()101010100.032()WpIWWpLLLLrLLrdBWWW(2)20lg1110520lg 51180()pWLLrdB9.已知空气密度0=1.213/kg m、空气声速c=340/m s。若两不相干波在声场某点的声压幅值分别为 5Pa 和 4Pa,问在该点的总声压(有效声压)和平均声能密度是多少?解:
5、文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8
6、Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L
7、10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV
8、10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1
9、E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码
10、:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6
11、B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5
12、 ZY8Y4X6B3D63/10222225441()12414.5()2222434.51.4610(/)221.23400pppPaApApPaepeDWmc10.在半自由声场中,一点声源辐射球面波。气温20、相对湿度 20%。在距声源 10m处,测得 10000 Hz 的声压级为 100 dB,问 100m处该频率的声压级为多少分贝?解:100220lg10020lg0.0062 100102121101 =100-20lg10-0.006290=79.4(dB)rLLrrppr11.某测点的背景噪声为65 dB,周围有三台机器,单独工作时,在测点处测得的声压分别为 70 dB、76 d
13、B、78 dB,试求这三台机器同时工作时,在测点的总声压级。解:0.10.10.1 700.1 6510.10.10.1 760.1 6520.10.10.1 780.1 6530.1 77.10lg(1010)10lg(1010)68.35()10lg(1010)10lg(1010)75.64()10lg(1010)10lg(1010)77.78()10lg(10LpLpBPaLpLpBPaLpLpBPaPLdBLdBLdBL780.1 75.640.1 68.351010)80.16()dB12.某点附近有 2 台机器,当机器都未工作时,该点的声压级为50 dB,若同时工作时,该点的声压级
14、为 60 dB,若其中 1 台工作时,则该点的声压级为55 dB,试求另 1 台机器单独工作时,该点的声压级为多少?解0.10.10.1 550.1 5010.10.10.1 600.1 53.35210lg(1010)10lg(1010)53.35()10lg(1010)10lg(1010)58.94()LpLpBPaLpLpBPaLdBLdB13.在某测点处噪声的倍频带声压级列于下表,计算该噪声的总声压级。中心频率/Hz 63 125 250 500 1000 2000 4000 8000 声压级 dB 98 101 103 102 99 92 80 60 解0.19.810.110.31
15、0.29.99.28.06.0110lg1010lg(1010101010101010)108.1()pinLpiLdB14.某声压在指定测点处,测得治理前,后的声压级如表中所示。计算治理前后的总响度和响度下降的百分率。中心频率/Hz 500 1000 2000 4000 8000 治理前声压级 dB 85 95 93 90 80 治理后声压级 dB 75 85 85 80 75 查图 2-11响度指数解文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8
16、H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6
17、文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8
18、Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L
19、10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV
20、10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1
21、E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码
22、:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D64/10倍频程 F=0.3 治理前响度指数分别为N1=18(sone),N2=50(sone),N3=55(sone),N4=50(sone),N5=30(sone)治
23、理后N1=10(sone),N2=23(sone),N3=29(sone),N4=23(sone),N5=22(sone)治理前总响度maxmax=()iNNFNN前=55+0.3(18+50+55+50+30-55)=99.4(sone)治理后总响度maxmax=()iNNFNN后=29+0.3(10+23+29+23+22-29)=52.4(sone)响度下降百分率为N-N99.4-52.4=100%=100%47%N99.4后前前15.在空间某处测得环境噪声的倍频程声压级如下表,求其线性声压级和A计权声压级。fe/Hz 63 125 250 500 1000 2000 4000 8000
24、 LP/dB 90 97 99 83 76 65 84 72 解(1)0.199.79.98.37.66.58.47.2110lg1010lg(1010101010101010)101.6()pinLpiLdB查图 2-12(2)A 计权后各中心频率声压值dB(A)分别为:90-26.2=63.8 97-16.1=80.9 99-8.6=90.4 83-3.2=79.8 76-0=76 65+1.2=66.2 84+1.0=85 72-1.1=70.9 0.16.388.099.047.987.66.628.57.09110lg1010lg(1010101010101010)92.3()pin
25、LpiLdB A16.在铁路旁某处测得:当货车经过时,在 2.5min 内的平均声压级为72dB;客车通过 1.5min内的平均声压级为68dB;无车通过时环境噪声约为60 dB;该处白天 12h 内共有 65 列火车通过,其中货车 45 列、客车 20 列,计算该地点白天的等效连续声级。解货车 72dB对应时间为 2.5*45/60=1.875h 客车 68dB对应时间为 1.5*20/60=0.5h 其余时间为 12-1.875-0.5=9.625h 文档编码:CH8H5R1E1L10 HV10B10P7L10F5 ZY8Y4X6B3D6文档编码:CH8H5R1E1L10 HV10B10P
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 完整 word 物理 污染 控制 习题 答案 第二
限制150内