CAJ | 학술논문

利用新研制的外筒旋转可调压可视化Couette流变仪,开展了强剪切流的空化试验,发现剪切力矩及瞬态温度对剪切空化的影响非常明显.通过传感器温度阶跃响应试验数据,求得温度传感器在静止液体内受阶跃温度变化时的表面传热系数.采用柱坐标系,基于试验获得的纯剪切力矩和瞬态传热微分方程,由数值计算方法求出不同时刻强剪切Couette流的瞬态温度,理论计算值与试验结果较为吻合,表明新的外筒旋转可调压可视Couette流变仪获得的纯剪切力矩和瞬态温度的准确性,以及间隙的均匀性.利用文献[9]的初步估算方法,也可求出强剪切Couette流的温度变化值.对比分析结果表明,所提方法校核精度高且适用范围广.
이용신연제적외통선전가조압가시화Couette류변의,개전료강전절류적공화시험,발현전절력구급순태온도대전절공화적영향비상명현.통과전감기온도계약향응시험수거,구득온도전감기재정지액체내수계약온도변화시적표면전열계수.채용주좌표계,기우시험획득적순전절력구화순태전열미분방정,유수치계산방법구출불동시각강전절Couette류적순태온도,이론계산치여시험결과교위문합,표명신적외통선전가조압가시Couette류변의획득적순전절력구화순태온도적준학성,이급간극적균균성.이용문헌[9]적초보고산방법,야가구출강전절Couette류적온도변화치.대비분석결과표명,소제방법교핵정도고차괄용범위엄.
By utilizing the newly developed visual Couette rheometer with its outer cylinder rotating and pressure adjustable, cavitation experiments of strong shear flow are carried out.It is found that the influence of transient temperature and shearing torque on shearing cavitation is very obvious.By experimental data of temperature step respon se of sensor,the convection heat transfer coefficient when the thermocouple is rooted in resting hot liquid and subjected to the step temperature change is obtained.In a cylindrical coordinate system,with the pure shearing torque and transient heat transr differential equation obtained from the experiment,the transient temperatures of strong shearing CoueRe flow at different time are calculated by using numerical method.The theoretical value is consistent with the experimental result,thus showing the correctness of pure shearing torque and transient temperature and the uniformity of gap obtained from the said Couette rheometer by using the preliminary estimation method,the temperature change value of strong shearing Couette flow is obtained.The comparison and analysis results show that the proposed method is highly accurate and widely applicable.