The Researches On The Mechanism Of Heat Transfer In The Pross Of Drilling Under The Condition Of Simulated Lunar Rock

In order to understand the regularities of heat distribution in the drilling process, this article is used to build a heat conduction differential equations about bit – lunar rock – cuttings through the analysis of the heat transfer process about drilling The simulation lunar rock, and it reveals the main influencing factors of the drill bit working temperature, an analytical method and the calculation method of the drill bit cutting face working temperature was given. Based on the analysis of the thermal power conversion about drilling lunar rock process, the heat distribution mode was given. Through the analytical calculation method with the experience calculation parameters, we get the mathematical expressions of bit temperature and we determines the influence of the temperature in the drill bit with the bit pressure、rotate speed and feeding speed, in order to simplify the calculation, we can get that the rising temperature is proportional to the square of forward speed in the case of bit pressure and the rotation speed stable.According to the nature of the moon rocks parameters, this paper used marble which have the consistent mechanical property and drill ability grade replace the simulated lunar, we get the mechanics parameters of marble through the experiment testing, and get the elastic modulus and Poisson’s ratio of marble by using vic-3d non-contact full strain measuring system, vic-3d system is a kind of digital image technology, which can get be tested the distribution of strain and displacement on the surface of the material in the experiment, and also can effectively get the modulus of elasticity and Poisson’s ratio of the rock efficiently.Then, we begin the simulated experiment in the room, the infrared thermal imager are used to get the heat distribution images of the process about the drilling simulated lunar rock. Used the infrared thermal image software to get the temperature field distribution of the simulated lunar rock and drill bit, Respectively to analyze the temperature field of the rock, we can get the rock temperature filed distribution characteristics and distribution, it looks like warhead shape distribution, and the temperature is higher when the rock is close to the bit, it affected decrease gradually far away from the bit. through the analysis on temperature field of drill bit, we get the temperature distribution in the process of drilling bit, and analyze the bit under steady state temperature, which gets the relationship of the drill bit temperature and the advance rate by compared with the calculation results, and verify the relationship of the drill bit rising temperature with the forward speed.