用波尔共振仪研受迫振动.doc

MATLAB作业 用波尔共振仪研究受迫振动 实验目的 学会进行简单设计性试验的基本方法； 测量摆轮受迫振动的幅频特性和相频特性。 仪器与用具 　　ＢＧ－２型波尔共振仪、电气控制箱 实验原理 １、有粘滞阻尼的阻尼振动 转角的运动方程　 当固有系数则 当时 所以　　 ２、周期外力作用下的阻尼振动 在外力矩驱动下运动方程为 通解为 稳态解为 稳态解的振幅和相位差分别为 　　　　　　　　　　　　 ３、电机驱动下的受迫振动 当外激励角频率时，系统发生共振，有极大值。阻尼系数越小，振幅越大 实验数据处理 1、阻尼系数的测量　 阻尼档位：1 10T=15.793 =1.579 振幅／（。） 振幅／（。） １０９ ６７ 0.487 0.063 １００ ６７ 0.494 ９１ ５５ 0.504 ８３ ５０ 0.507 ７４ ４５ 0.497 2、幅频特性和相频特性的测量 阻尼档位：1 振幅极大值=143 “强迫力 振动周期” 刻度 强迫力矩 10驱动 周期/s 振幅/（。） 弹簧固有振动 周期/s 0.60 15.409 71 1.580 150 147.701 1.025 0.247 1.30 15.547 105 1.576 134 130.839 1.014 0.539 1056 15.607 125 1.573 119 116.461 1.008 0.764 1.76 15.658 139 1.571 105 101.886 1.003 0.944 2.00 15.683 143 1.570 94 92.723 1.001 1.000 2.08 15.717 143 1.570 89 86.067 0.998 1.000 2.18 15.734 143 1.570 85 82.175 0.997 1.000 2.58 15.810 135 1.571 69 68.059 0.993 0.891 2.90 15.883 123 1.573 60 58.461 0.990 0.739 3.40 16.011 101 1.576 45 45.001 0.984 0.498 5.00 16.251 68 1.580 29 29.371 0.972 0.226 作业、讨论 当空气中自由振动系统共振时，真大振幅会变为无穷大吗？ 答：不会，驱动力角频率达到固有角频率时，振幅达到最大，之后不会增大。 在实验中如何判断受迫振动达到稳定振动状态？ 答：大振幅不再随强迫力变化而变化时，则已经达到稳定振动状态。 loan management (post) review: 1, approval criteria have been implemented; 2, the contract is correct; 3, in line with the contract, payment; 4, no other major cases against loan security;、Reviewed by: date of record form 9: qilu bank borrowing by single years of maximum amount a maximum no-loan borrowers: borrowers: ... Borrower name number, line of credit expiry date year month day to year month day maximum number of years in the loan contract are the top line opened, the borrowed and requested your bank opened credit lines above, is hereby requested. Borrower signature: date agreed to open credit lines. Customer Manager signature: date agreed to open credit lines. Loan review signature: date line cancellation-I did not use the loan amount, your bank credit lines to be cancelled. -Credit loan principal repayment, your bank