D-Zero Colling Loops

This report provides the necessary sizing for the LN{sub 2} cooling coils in the D-Zero cryostats. Natural convection from finned tubes will be the means of cooling the cryostats and their contents until such time as liquid can be made by condensing. Each cryostat will contain three separate cooling runs. Two runs will be cooldown and the other steady state. These runs will be placed in each cryostat as shown in figure 3, 4a and 4b. By assuming a 100 K tube wall temperature, tube diameter (3/4-inch) and wall thickness (0.065-inch) and the total length of tube (2 x 2940-inch + 1463-inch), the heat transfer can be calculated. Table 1 was calculated from relations in 'Handbook of Heat transfer Fundamentals' for free convection, pages 6-34 through 6-40