NGHIEN cuu-TRAO DOI KHAO SAT DAO DONG RIENG CUA KHOANG HANH KHACH DE DANH GIA DO N CUA XE BUS CO LON LAP RAP TAI VIET NAM STUDY ON MODAL APPROACH OF THE SPACE INSIDE THE BUS BODY TO ASSESS THE NOISE AND VIBRATION OF 45 SEATS BUS ASSEMBLY IN VIETNAM Du Tuan Dat, Nguyen Tien Diing Trudng Dai boc Bach khoa Ha Ndi TOM TAT Trong nhimg ndm qua, cdc nhd sdn xudt to nu&c da lap rdp rdt nhieu ddng xe bus ca l&n Viec nghien cim phdt tnen de tdng tinh tien nghi cho ngu&i ngoi tren xe luon Id vdn de d quan tdm nghien aim, on rung la mot nhimg chi tieu de ddnh gid chdt hcangxe De ddnh gid vd hodn thien ket cdu cho sdn phdm khung vo, viec xdc dinh dao dong rieng nhdm tim r cdc dang vd viing tdn so co khd ndng cong hu&ng la bu&c quan trong qud trinh nghien cu on rung cua xe bus vd la vdn de ddng duac quan tdm nghien cuu Bdi bdo trinh bdy mot so ket qu khdo sdt dao dpng rieng cua khung vo vd khoi khong khoang hdnh khdch cua xe bus 45 cho la rdp tai Viet Nam Nghien cuu ndy tap trung vdo viec xdy dung mo hinh rung on de xdc dinh cdc dang vd vung tdn so dao dpng rieng cua khung vo, ldm ca s& cho bdi todn phdn tich on rung xe bu Tir khoa: Dang dao dpng rieng; Tdn so; Mo hinh phdn tu hihi han; Xe bus 45 cho ABSTRACT In recent years, domestic car manufacturers have assembled many large buses Research and development to increase comfort for people sitting on cars is always a matter of concern, in which noise and vibration are indicators to assess vehicle quality In order to evaluate and improve the structure of the bus body, the specific vibration determination ofeigenmodes and are of resonant frequency is an important step in the noise and vibration study process and that is a matter of concern The paper presents some studied results of vibration of the body and the space inside the bus body of the 45-seat bus assembly in Vietnam This study focuses on building of nois and vibration model to determine the eigenmodes and individual oscillation frequency of bus body as a basis for the noise and vibration analysis of bus Keywords: Modal approach, resonant frequency, FE model 45-seats bus ISSN 0866 - 7056 TAP CHi CO KHi VIET NAM, Sd 1+2 nam 2019 www.cokhivietnam.vn NGHIEN cuu-TRAO DCI TONG QUAN Cdng nghe san xuat khung, vd xe khach ndi chung va xe bus cd ldn d Viet Nam dang dugc thuc hien theo cac qui trinh cdng nghe truyen thdng vdi dac diem chung la: Khung xuong bang thep, bgc vd bang tdn hoac composite, cac khung xuang dugc lien ket vdi bang cac khdp ndi va bu-ldng Khi d td hoat ddng tren dudng, nd lien tuc nhan dupe cac kich thich gay rung ddng tir nhieu ngudn khac Nhimg kich thich gay rung dgng khung vd xe va he qua cua nd la tieng dn khoang xe, gay khd chiu cho ngudi lai va hanh khach, giam tinh tien nghi su dung De giam thieu nhiing tieng dn nay, hien phan tich thyc nghiem am ben xe dang dugc su dung tai cac hang xe nhung vdi chi phi dau tu phdng thi nghiem de phan tich la rat Idn nen viec tinh toan kiem tra bang md phdng trude thir nghiem thyc tien la can thiet Nghien ciiu dn rung d td la mdt van de rgng va rat phiic tap Tuy nhien, nhu cau cang cao ve tinh tien nghi ciia phuong tien viec nghien cim tieng dn tren d td da thu hiit sy quan tam ciia nhieu nha khoa hgc tren the gidi ndi chung va Viet Nam ndi rieng Hien nay, de phan tich bai toan rung dn cd rat nhieu phucmg phap kbac nhau, phuang phap phan tir hiru ban (PTHH) hien dang dupe sir dyng va phd bien [1, 2] thi dl cd tbi danh gia va cai thien tinh tien nghi vl rung dn la nhu cau can thiet cho cac nhdm chung loai san pham Vdi tinh chat nhu vay, viec danh gia rung dn cua xe bus cd ldn thuc su la cin thiet Xuit phat tir nhiing danh gia tren, ttong bai bao nay, nhdm tac gia tap trung nghien ciiu xay dung md hinh cho phep khao sat dn mng cua khdi khdng ben khoang hanh khach cua xe bus co ldn THACO TB120SL-375IIL Cac ket qua budc dau nham khao sat cac dang dao ddngriengcua khung vd bao ngoai va khoi ben vd xe, la ca sd de xac dinh cac tin sd gay cdng hudng cua khung vd va khdi ben khoang hanh khach Md hinh cho phep md rdng nghien ciiu khao sat miic on rung tai tan sd gay cdng hudng, danh gia anh hudng ciia chiing den dp dn tai cac vi tri khoang hanh khach ciia xe bus cd ldn XAY DlTNG M HINH P H A N TU" HUtJ HAN DE PHAN TICH DAO DONG CUA KHOI KHI TRONG KHOANG HANH KHACH XE BUS COf L N Ddi tugng nghien cuu la xe bus co Idn THACO TB120SL-375ni Ciu true cua khung vd xe bao gdm phan khung xuong va tam vd, ben khoang xe cd bd tri ghe ngdi va cac tbiet bi khac a Gia thiet mo hinh phan tu- hihi han Rung dn la mdt chu de mdi nhung van de nghien cuu phat trien ve rung dn tren cac san pham lap rap nude hien cdn rit han che Cac hudng nghien ciru tap trung vao viec xay dung mdt sd md hinh xe khach cd nhd va trung binb, dd viec danh gia tieng dn bang mpt sd thiet b; va thir nghiem phdng thi nghiem [3,4] Ngoai ra, nhu de cap d tren, viec nghien ciiru danh gia vdi timg ddi hipng cu - Cac bd phan khac tren vd xe dupe tbiet ke lien khdi, bd qua cac mdi lap ghep nhu dinh tan, ban, ban ll - San xe lien ket vdi chassi thdng qua cac vi tri bit bu Idng (dugc coi la lien kit ciing) De giam khdi lugng tinh toan, dp phiic tap ciia bai toan ma khdng anh hudng din tin cay ISSN 0866 - 7056 TAP CHi CO KHi VIET NAM, So I +2 nam 2019 www.coldiivietnam.vn NGHIEN cuu-TRAO DOI cua ket qua tinh toan, khoang hanh khach dupe tach rieng vdi cau tnic tdng thd ciia chassi b Xay du-ng mo hinh 3D khung vd vk khoi khdng ben khoang hanh khach cua xe bus co* ldn Md hinh hinh hgc 3D ciia khdi khdng khoang hanh khach duge xay dung theo cac ban ve chi tiet tai lieu thilt kl ky thuat xe bus THACO TB120SL-W375ni cua nha san xuit Vdi bai toan md phdng tieng dn xe khach giudng nam, ddi tugng can quan tam khao sat la khoang hanh khach bao gdm khung vd ben ngoai va khdi khdng ben khoang xe Phan khung xe bao gdm chassi, khung xuong dugc che tao tir cac thep hop cd kich thudc 50x50x2.0mm hoac 40x40x1.4mm ghep cimg vdi Phan vd xe khoang hanh khach dugc cau tao tir cac mang co ban la cac tam tdn cd chieu day tieu chuan mm, rieng ddi vdi tam san xe dugc cau tao tir cac tam nhdm cd dp day 4mm Trong nghien ciiu nay, phan mem Solidworks dugc sir dyng de xay dung md hinh 3D khdi khdng ben khoang hanh khach vi nd cd the lien ket true tiep vdi phan mem phan tich dn rung (Ansys) de giam thieu dugc sai lech chuyen ddi giiia cac md hinh (hinh I) Sau da dung dugc khung xuong va vd xe bus, khdi khdng khoang hanh khach dugc xay dyng bat diu tu ldp cimg cua phin khung vd Md hinh khdi khdng cua khoang hanh khach dugc xay dyng tren ket cau khung hoan chinh, cac cira dong kin, cd ke den phan khdng gian bi chiem chd cua ghe va hanh khach (hinh 2) Hinh Mo hinh chassi vd khung xuang Hinh Mo hinh 3D khung vd bao ngodi vd khdi khdng ben xe bus c Gan vat lieu Phan khung vd khoang hanh khach xe khach giudng nam sir dung vat lieu la hop kim nhdm vdi cac thdng sd dugc cung cap true tiep tii' thu vien vat lieu cua Ansys Khdi ben khoang hanh khach ap dung vat lieu la khdng kbi vdi cac thdng sd ciing dugc cung cap bdi phan mem Mdt sd thdng sd chinh bao gdm: Khdi lupng rieng 1.204 kg/m^; Van tdc truyen am 242.24 m/s; Ap suat tieu chuin 2e-5 Pa ^ ISSN 0866 - 7056 TAP CHi CO KHi VIET NAM, Sd +2 nam 2019 www.coldiivietnam.vn NGHIEN cuu-TRAODOI d Xac dmh kieu phan tu Phuang phap phan tich phan td hihi ban cung cip mdt ky thuat sd hda dang tin cay de phan cac thilt k l ky thuat Qua trinh dugc bit dau vdi viec md phdng hinh dang hinh hpc cua md hinh Sau do, chuong trinh se chia md hinh nhiing phan nhd cd hinh dang don gian (gpi la cac phin di) lien ket vdi tai cac niit (node) Bai toan phan tich dn rung se giai quyet cac phuong trinh tuong tac ket cau - chat luu Vi thi md hinh ciing se phai sir dung ddng thdi cac kieu phan tir ket cau va phan tir chat luu (trudng hgp la khdng khi) Phan tii' kit ciu dupe sir dung la SHELL181 cdn phan hi chit luu la FLU1D30 SHELL181 la phin tir dac thil cho cac ket cau dang vd cd chieu day mdng, bao gdm mit vdi bac ty tai mdi mit, cho phep md ta hieu img cua ap suat phan bo tren be mat Phan tir FLUID30 dupe sir dung de md ta mdi trudng chat luu va be mat lien ket ran - ldng cac bai toan tuong tac ket cau - chat luu Phan tu FLUID30 cd mit vdi bac tu tai mdi niit, cho phep thiet lap dang vat lieu hap thy am tai be mat tuong tac Thudc tinh ciia cac dang phan tu cd thudc tinh cua phan mem [3] Viec kiem soat chat lugng ludi dugc kidm soat theo cac tieu chuin danh gia ludi cua phin mem de Ansys (rihu he sd lech (Aspect ratio), he sd Jacobian (Jacobian Ratio), lech (Skewness), chat lugng phan tir (Element Quality)) da dugc phin mim dl Hinh Md hinh PTHH khung vd vd khdi khong ben khoang hdnh khdch g Dat tai len mo hinh kit can Trong bai toan PTHH phan tich de tun sd cac tan sd rieng va dang rieng thi tai dugc dinh nghia tren md hinh PTHH chinh la cac rang budc ve chuyen vi dugc md ta tren hinh Day chinh la cac vi tri dugc han vdi cac vi tri bat he thdng treo Liic ta coi he thong khung vd dugc cd dinh tai cac vi tri bat vdi he thdng treo (hinh 4) e Xay dung mo hinh ludi Tao ludi la mdt budc cd tinh quyet dinh cac phan tich thiet ke Qua trinh tao ludi ty ddng Ansys sinh ludi dua tren kich cd phan hi chung, mirc sai lech va cac dac dilm kiem soat ludi De kiem soat ludi dam bao qua trinh giai bai toan pbin tir hiiu han la nhd nhat ta can quan tam den mat ludi va phan hi phii hgp vdi cac dieu kien cua bai toan Md hinh PTHH cua khung vd va cua khdi khdng ben khoang hanh khach xe bus dugc the hien tren hinh Hinh 4: Cdc vi tri gi&i hgn chuyin vi KHAO SAT TAN SO VA DANG DAO DONG RifeNG CUA KHOI KHONG KHI BEN TRONG KHOANG HANH KHACH Ddi vdi bai toan phan tich tieng dn khoang hanh khach d td, khoang tin sd dugc quan tam la hi 20 - 200 Hz Nhirng nguyen ISSN 0866 - 7056 TAP CHi CO KHi VIET NAM, S6 1+2 nam 2019 wTvw.cokhivietnam.vn NGHIEN c u u - T R A O D(!)l nhan quan trgng gay tieng dn ben xe la sy rung ddng cua dgng ca va rung ddng tac dpng tir mat dudng vdi dai tin sd thip [4] Tieng dn cd the tang len su cdng hudng cua khdi ben khoang Trong bai toan xac dinh dao ddng rieng, can thiet phai xac dinh cac tan sd, cac dang dao ddng rieng cua vd xe va khdi ben trong, tir dd xac dinh cac tin sd rieng cd the gay edng hudng Kit qua phan tich (bang 1) the hien cac 30 dang dao ddng rieng dau tien ciia khung vd xe bus va cac tan sd dao ddng tuong iing Ket qua cho phep xac dinh mgt sd tan sd gay rung ddng va chuyen vi Idn cho khung vd xe, cd the tao len cac miic ap suat am gay tieng dn Ket qua ve chuyen vi dac trung (tinh theo mm) cbo mgt sd dang dao ddng dien binh dugc the hien hinh va hinh Bdng Tdn sd dao ddng riing cua khung vd: Dang Tan s6 (Hz) Dang Tan s6 (Hz) Dang Tan so (Hz) Dang Tkas6 (Hz) Dang Tan so (Hz) 20.8 28.7 13 43.9 19 62.1 25 77.8 21.3 30.7 14 44.7 20 63.3 26 78.2 22.9 31.9 15 47.0 21 65.6 27 82.6 24.4 10 32.2 16 51.0 22 69.4 28 103.6 25.2 11 33.5 17 52.1 23 71.7 29 107.5 27.5 12 42.8 18 53.9 24 74.8 30 112.2 i ^ ^ Hinh Chuyen vi trin vd xe & dgng dao dpng thir (tan so 22.9 Hz): Phdn vd ndc xe dao dpng mgnh Hinh Chuyen vi tren vd xe & dgng da (tdn sd 22.9 Hz): Phdn vd cgnh xe dao dp Doi vdi khdi khdng ben khoang hanh khach, dai tin sd phan tich 20 - 200 Hz da xac dinh dugc 89 tan sd rieng cua khdi Cac dang va tan sd dao ddng rieng tim thiy dugc tdng hop bang Cac ket qua thu dugc cho phep xac dinh dugc viing cd ap suit khdng Idn (tinh theo MPa) cung nhu dang phan bd ciia ap suat tuong iing vdi mdi dang dao ddng *- ISSN 0866 - 7056 TAP CHi CO KHi VlfiTNAM, Sd 1+2 nam 2019 www.cokhivietnam.vn NGHIEN CUU - TRAO D C I d Xac dinh kieu phan tii Phuong phap phan tich phan tu huu ban cung cap mdt ky thuat sd hda dang tin cay de phan cac thilt kl ky thuat Qua trinh dugc bat dau vdi viec md phdng hinh dang hinh hgc ciia md hinh Sau dd, chuang trinh se chia md hinh nhirng phan nhd cd hinh dang dan gian (ggi la cac phan tu) lien ket vdi tai cae niit (node) Bai toan phan tich dn mng se giai quyet cac phuong trinh tuong tac ket cau - chat luu Vi the md hinh ciing se phai sir dyng ddng thdi cac kieu phan tu ket cau va phan tir chat luu (trudng hgp la khdng khi) Phan tu ket cau dugc sir dung la SHELL181 cdn phan tli chit luu la FLUID30 SHELL 181 la phin tir dac thu cho cac ket cau dang vd cd chieu day mdng, bao gdm nut vdi bac hi tai mdi nut, cho phep md ta hieu img cua ap suat phan bd tren be mat Phan tir FLU1D30 dupe su dung de md ta mdi trudng chat luu va be mat lien ket ran - ldng cac bai toan tuong tac kit cau - chat luu Phan tir FLUID30 cd niit vdi bac ty tai mdi mit, cho phep thilt lap dang vat lieu hap thu am tai be mat tuang tac Thudc tinh cua cac dang phan tir cd thugc tinh cua phan mem [3] Viec kiem soat chat lupng ludi dugc kiim soat theo cac tieu chuan danh gia ludi cua phin mem de Ansys (nhu he sd dp lech (Aspect ratio), he sd Jacobian (Jacobian Ratio), lech (Skewness), chat lupng phin hi (Element Quality)) da dugc phan mem de Hinh Md hinh PTHH khung vd vd khdi khong ben khoang hdnh khdch g Dat tai len mo hinh ket cau Trong bai toan PTHH phan tich de tim sd cac tan sd rieng va dang rieng thi tai dugc dinh nghia tren md hinh PTHH cbinh la cac rang budc ve chuyen vi dugc md ta tren hinh Day chinh la cac vi tri dugc han vdi cac vi tri bat he thdng treo Luc ta coi he thdng khung vd dugc cd dinh tai cac vi tri bat vdi he thdng treo (hinh 4) e Xay dung mo hinh ludi Tao ludi la mdt budc cd tinh quyit dinh cac phan tich thiet ke Qua trinh tao ludi ty ddng Ansys smh ludi dua tren kich cd phan hi chung, miic sai lech va cac dac dilm kiem soat ludi De kiem soat ludi dam bao qua trinh giai bai toan pbin tii hiru ban la nhd nhat ta can quan tam den mat dp ludi va phin hi phu bgp vdi cac dieu kien cua bai toan Md hinh PTHH ciia khung vd va ciia khdi khdng ben khoang hanh khach xe bus dugc the hien tren hinh Hinh 4: Cdc vi tri gi&i hgn chuyen vi KHAO SAT TAN SO VA DANG DAO DONG RIENG CUA KHOI KHONG KHI BEN TRONG KHOANG HANH KHACH Ddi vdi bai toan phan tich tieng dn khoang hanh khach d td, khoang tin sd dugc quan tam la tir 20 - 200 Hz Nhirng nguyen ISSN 0866 - 7056 TAP CHi CO KHi VIET NAM, Sd 1+2 nam 2019 www.cokhivietnam.vn NGHIEN CUU-TRAO D | nhan quan trgng gay tieng dn ben xe la sy rung ddng cua ddng co va rung ddng tac ddng tir mat dudng vdi dai tin sd thip [4] Tieng dn cd the tang len sy cgng hudng cua khdi ben khoang Trong bai toan xac dinh dao ddng rieng, can thiet phai xac dinh cac tan sd, cac dang dao ddng rieng cua vd xe va khdi ben trong, tir dd xac dinh cac tan sd rieng ed the gay cgng hudng Ket qua phan tich (bang 1) the hien cac 30 dang dao ddng rieng dau tien ciia khung vd xe bus va cac tin sd dao dgng hrcrng iing Ket qua cho phep xac dinh mdt sd tan sd gay rung ddng va chuyen vi ldn cho khung vd xe, cd the tao len cac miic ap suat am gay tieng dn Ket qua v l chuyin vi dac trung (tinh theo mm) cho mdt sd dang dao ddng dien hinh dugc the hien hinh va hinh J1 Tdn sd dao dpng riing cua khung vo: Dang Tan so (Hz) Dang Tan so (Hz) Dang Tlins8 (Hz) Dang Tan sd (Hz) Dang Tan so (Hz) 20.8 28.7 13 43.9 19 62.1 25 77.8 21.3 30.7 14 44.7 20 63.3 26 78.2 22.9 31.9 15 47.0 21 65.6 27 82.6 24.4 10 32.2 16 51.0 22 69.4 28 103.6 25.2 11 33.5 17 52.1 23 71.7 29 107.5 27.5 12 42.8 18 53.9 24 74.8 30 112.2 Hinh Chuyen vi trin vd xe & dgng dao dpng thit- (tdn so 22.9 Hz) • Phdn vd ndc xe dao ddng mgnh Hinh Chuyin vi trin vd xe a dgng dao ddng thic (tdn so 22 Hz): Phdn vd canh xe dao dpng mgnh Ddi vdi khdi khdng ben khoang hanh khach, dai tin sd phan tich 20 - 200 Hz da xac dinh dugc 89 tan sd rieng cua khdi Cac dang va tan sd dao ddng rieng tim thiy dugc tdng hgp bang Cac ket qua thu dugc cho phep xac dinh dugc vung cd ap suit khdng ldn (tinh theo MPa) ciing nhu dang phan bd ciia ap suat tuong iing vdi mdi dang dao ddng '^ ISSN 0866 - 7056 TAP CHi C O KHi VIET NAM, So 1+2 nam 2019 www.cokhivietnam.vn NGHIEN CU'U-TRAOD6I J Tdn so dao ddng rieng ciia Ithoi lihong Ichi Ichoang hdnh khdch: „ I'»"8 Tan so , (Hz) 10 11 12 71.8 72.1 76.0 77.7 81.4 82.4 ; Tan so "'"S (Hz) i 28.7 42.7 56.0 63.3 70.2 70.5 Dang 13 L ''' 15 16 17 18 Tan so (Hz) 87.0 89 91.2 94.8 98.2 99.3 Dang 19 20 21 22 23 24 n Tan so (Hz) Dang 99.8 101.9 103.6 107.0 110.7 112.3 25 26 27 28 29 30 Tan si (Hz) 114.3 115,6 121.0 123.1 1247 1252 Hinh Chuyen vi tren vo xe d dgng dao dpng thic (tdn sd 22.9 Hz) Phdn vd ndc xe dao dong mgnh Hinh Chuyen vi trin vd xe & dgng dao dpng thit (tdn so 22.9 Hz): Phdn vo cgnh xe dao d KET LUAN Ngay nhan bai: 18/01/2019 Ngay phan bien: 12/02/2019 Ket qua khao sat dao ddng rieng ciia khung vd va khdi khdng ben khoang hanh khach cua xe bus 45 chd bang md hinh ly thuyet cho phep xac dinh dugc cac dang dao ddng rieng va cac vung tan sd cdng hudng cd the xay ket cau Day la nhirng ket qua budc dau dugc sir dung lam co sd cho cac bai toan phan tich ket cau va tdi uu hda ket cau nham giam thieu dn rung thiet ke khung vd Ngoai ra, md hinh ciing dugc sir dung viec danh gia miic ap suat am khoang hanh khach, tir cd the dinh hudng cho bai toan lya chgn vat lieu hgp Iy ciing nhu cac bien phap ky thuat de giam tiing dn, dam bao cac yeu cau ve tinh tien nghi cho ngudi lai va hanh khach b-en xe, tang chat lugng cua san phim xe bus dugc san xuat lap rap nude • Tai lieu tham khao: [1] D.J Nefske, J.A Wolf, Jr and L.J Howell: "Structural-acoustic finite element analysis of ihe automobile passenger comparment: a review of curenl practice" Journal of Sound and Vibration 80,247-266, 1982 [2] Muller, M„ Eckel, H , Leibach, M., and Bors, W., "Reduction of Noise and Vibration in Vehicles by an Appropriate Engine Mount System and Active Absorbers." SAE Technical Paper 960185,1996 [3] Dao Ngoc Diep "Nghiin cmi 6n rung dong cua vo xe mini buyt sdn xudt tgi Viet Nam", Lu|n an tien sT, Hoc vien Ky thuat Quan su, 2008 [4] Le Quynh Mai, (2013), bao ve luan an tiln sy: "Khao sal on rung khung vo to khdch 29 cho" Tap chi Ca Viet Nam, s6 12/2013 [5] ANSYS Release 13.0: "ANSYS Workbench User's Guide",2010 ISSN 0866 - 7056 TAP CHi CO KHi VIET NAM, Sd 1+2 nam 2019 www.cokhivietnam.vn ... vd xe & dgng dao dpng thit- (tdn so 22.9 Hz) • Phdn vd ndc xe dao ddng mgnh Hinh Chuyin vi trin vd xe a dgng dao ddng thic (tdn so 22 Hz): Phdn vd canh xe dao dpng mgnh Ddi vdi khdi khdng ben khoang. .. vi trin vd xe & dgng dao dpng thir (tan so 22.9 Hz): Phdn vd ndc xe dao dpng mgnh Hinh Chuyen vi tren vd xe & dgng da (tdn sd 22.9 Hz): Phdn vd cgnh xe dao dp Doi vdi khdi khdng ben khoang hanh... TICH DAO DONG CUA KHOI KHI TRONG KHOANG HANH KHACH XE BUS COf L N Ddi tugng nghien cuu la xe bus co Idn THACO TB120SL-375ni Ciu true cua khung vd xe bao gdm phan khung xuong va tam vd, ben khoang