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Highlights • The total heat load has been predicted by finite element method calculation, and verified by experiment. • An additional radiation shield was designed to reduce heat load of helium phase separator. • The helium phase separator with a cryocooler re-condenses helium and stores liquid helium stably. Abstract Improvements in simulation and practice for the heat load of a helium phase separator are discussed. The separator cryostat (volume 100 L, cooling capacity 1.5 W at 4.2 K) re-condenses and stores liquid helium. An additional radiation shield was designed to minimize the radiative heat transfer and to decrease the heat conduction. The experimental results indicate that the heat load of the separator was decreased from 5.56 W to 1.555 W, a gain about 4 W of heat load, which is an improvement by 72%. Liquid helium (50 L) was stored in the separator stably for more than 90 h. Software implementing the finite-element method (FEM) was used to predict the temperature distribution of pipe fittings and the separator heat load with or without the additional radiation shield. The results of these simulations show that the temperatures of the pipe fittings were significantly decreased in the separator with additional radiation shields. For the heat load, the trends of simulation and experimental results were similar. This work provides a simple and effective method to minimize the radiation heat load of a separator. In this paper, we discuss in detail the improvements of the model, the experimental setup and the results of comparisons between experiments and simulations. [ABSTRACT FROM AUTHOR]

To improve the hot-pressing process currently employed in laminated object manufacturing (LOM), an innovative heating-and-pressing separation system is proposed, and heat transfer problems of this system are investigated. A thermal model is first established. It is solved numerically by the finite element method (FEM) software ANSYS, and verified by experiments. Based on the numerical solution under various operating conditions, it is found that the operating temperature of an adhesive can be reached quickly when the heater is maintained at a higher temperature, corresponding to a deeper heat-affected zone. This shortcoming can be effectively reduced if the speed of the heater is increased. Hence, a higher heater temperature together with a higher moving speed is suggested to shorten processing time and promote manufacturing efficiency. Through analysis, the appropriate distance between the roller and the heater, so as to obtain finished parts of high quality, is determined. [ABSTRACT FROM AUTHOR]

Abstract: A transfer system for liquid nitrogen (LN2) installed at National Synchrotron Radiation Research Center (NSRRC) to provide LN2 required for the superconducting equipment and experimental stations has a LN2 transfer line of length 160m and pipeline of inner diameter 25mm, a phase separator (250 L) and an automatic filling station. The end uses include two cryogenic systems, one Superconducting Radio Frequency (SRF) cavity, five superconducting magnets, monochromators for the beam line and filling of mobile Dewars. The transfer line is segmented and connected with bayonet couplings. The aim of this work was to investigate, by numerical simulation, the effects on the heat load of the gap thickness of the bayonet assembly and the thickness of vacuum insulation. A numerical correlation was created that has become a basis to minimize the head load for future design of bayonet couplings. [Copyright &y& Elsevier]