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AbstractThe original Translation, Confinement, Sustainment (TCS) experiment was upgraded [TCS Upgrade (TCSU)] to provide an ultrahigh vacuum (UHV) environment with modern discharge cleaning and wall-coating technologies. This has allowed rotating magnetic field formed field reversed configuration plasma temperatures to increase from the TCS radiation-dominated tens of electron volts to >200 eV (Te+ Ti), and FRC magnetic fields to double. The improvements are directly attributable to reduced impurity levels and reduced plasma recycling losses. Some of the technologies utilized to achieve these results included replacing O-rings with wire and conflat seals; developing high-temperature, differentially pumped, elastomeric seals for bonding extremely large quartz tubes (needed for rapid field penetration) to the stainless steel vacuum chambers; and using heater blankets for vacuum baking. Extensive testing using electron microprobe and various spectroscopic techniques was performed to establish appropriate UHV cleaning and handling methods.

The surface and interior temperature distribution in a section of boiler tubing under normal symmetric radiation from the furnace has been investigated by G. M. Dusinberre and others, and reported on in a discussion of data furnished by W. F. Davidson. In the same issue such problems in heat conduction are also treated by Paschkis using the method of electrical analogy, and by Emmons using the numerical method of obtaining approximate solutions; and in the reported discussion of the latter Dusinberre points out that the numerical method, carried out to the needed accuracy, checks the analytical solution and results are obtained with greater ease. The analytical method of Fourier, previously confined to the symmetric case of normal radiation, is here extended to the unsymmetric case where radiation from the fire is received obliquely and with consequent shadowing effect from adjoining tubes. An advantage of this investigation is that it supplies a general mathematical expression for temperature distribution under parallel radiation received at any angle with the boiler wall normal, thus affording a check on results that sometimes may be obtained easier by other methods. A further advantage is that this general mathematical expression makes it fairly easy to compare temperature gradients and hence rates of the heat transfer as done herein for various obliquity angles of received radiation.