Theoretical calculations of circulating pressure of chilled water system in operating mode;

The influences on freezing-drying of carrot under the modes of applying constant pressure,cyclic pressure and first constant then cyclic pressure are carried out through experiment with radiant heating.

In order to studying the corner strength performance of the rout & return system of Aluminum-Plastic Composite Panel(APP) for curtain walls under the wind loading,a testing instrument was made to test the corner strength performance under cyclic pressure,and the experiment was carried on for three kinds of APP made by different aluminum alloys.

It shows that (1) there is an optimum pressure which can make the drying time shortest; (2) higher the range of cyclic pressure, shorter the drying time, however it don t work to change the cycle of cyclic pressure ; (3) Freeze-drying with a constant pressure is better than drying with cyclic pressure; (4) the influence o.

According to the characteristics of reverse circulation kill and the basic principle of conservation of mass,momentum and energy,a calculation model of wellbore temperature field of reverse circulation kill process was established.

The combination of the fluid powered central hollow DTH hammer with the hydraulic reverse circulation con coring process eliminates the core blockage, resulting in higher drilling efficiency and longer bit life, and providing a good application prospec