tailieunhanh - Using inverse method for evaluating thermal characteristics of a micro high speed motorized spindle

Results show that inverse solutions agree with experimental data based on temperatures at only one measurement point. Influence of speed on heat sources and temperatures is indicated. | Journal of Science and Technology 54 (5A) (2016) 238-247 USING INVERSE METHOD FOR EVALUATING THERMAL CHARACTERISTICS OF A MICRO HIGH SPEED MOTORIZED SPINDLE Ngo Thi Thao1, Than Van The2, * 1 Faculty of Mechanical Engineering, Hung Yen University of Technology and Education, Khoai Chau, Hung Yen, Vietnam. 2 Ph. D. Program of Mechanical and Aeronautical Engineering, Feng Chia University, No. 100 Wenhwa Rd., Seatwen, Taichung, Taiwan 40724, * Email: Received: 15 July 2016; Accepted for publication: 3 December 2016 ABSTRACT A combination of finite element and conjugate gradient methods to establish an inverse method for estimating heat sources as well as temperatures of a micro high speed motorized spindle is presented in this article. The proposed method is simple in constructing the direct problem by using COMSOL software. Experiment setup and measurement process are introduced. Results show that inverse solutions agree with experimental data based on temperatures at only one measurement point. Influence of speed on heat sources and temperatures is indicated. Temperature distribution in the spindle is also given and discussed. From these findings, it can be said that the proposed method is appropriated for inversely determining the heat source in micro high speed motorized spindle. The obtained results provide useful information to estimate thermal deformation. Keywords: inverse method, thermal characteristics, heat source, motorized spindle, COMSOL software. 1. INTRODUCTION Thermal problems always exist in any spindle and further cause inaccuracy in machine tools. Understanding thermal characteristics in high speed spindle can help us to avoid or compensate thermal errors for improving precision of machine tools. A lot of researchers have built the thermal model of the spindle to explore heat transfer process and carry out the thermal results. Bossmanns and Tu [1] applied finite different method to construct a thermal model for high .