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This paper describes a new method for calculating the performance of pressure gain combustors for gas turbine applications. The method judges the value of a combustor based on the flow’s increased potential to do shaft work from combustor inlet to exit. This potential is defined as the work that could be extracted from the flow by a reversible adiabatic turbine exhausting to the combustor supply pressure. A new performance metric, the Rayleigh efficiency, is defined as the increased potential of the flow to do shaft work divided by the heat input. A novel control volume analysis is used, which directly links this performance metric to source terms within the combustor. Two primary source terms are shown: The first is a thermal creation term, which occurs in regions of the flow where combustion heat release occurs at pressures above that of the environment and acts to raise the flow’s potential to do shaft work. The term is a nonlinear analog of Lord Rayleigh’s acoustic energy creation term, from his 1878 thermoacoustic criterion. The second term is a viscous destruction term that always acts to reduce the flow’s potential to do shaft work. In the final part of the paper, the utility of the method is demonstrated using experimental measurements and computational predictions from a SNECMA (Société nationale d'études et de construction de moteurs d'aviation)/Lockwood-type valveless pulse combustor. The analysis enables a number of previously unanswered questions about pulse combustors to be answered.

Commercially prepared zonally and chromatographically purified bivalent (A/England-B/Mass) and monovalent (B/Hong Kong) inactivated influenza vaccines were given to 438 individuals 6-33 years old. The vaccines had been examined for antigen content by chick cell agglutination (CCA) tests and electron microscopic particle count determinations. Endotoxin and pyrogen content were determined by limulus amebocyte lysate (LAL) and rabbit pyrogenicity assays; and egg-associated protein contamination was estimated by total protein and single radial immunodiffusion assays. Although great differences (10-200-fold) were found in the amount of endotoxin or pyrogen in the vaccines, no significant differences were found in the febrile responses they induced. Both bivalent and monovalent vaccines induced fever of greater than or equal to 38 C at a rate of approximately 3 1/2-4% above background. The febrile responses were most frequent at 24 hours after inoculation and a higher rate was observed in children than adults. Local reactions consisting of tenderness, erythema or induration were seen in from 20-57% of the recipients and also were unrelated to the pyrogenic or host-derived materials in the vaccines. Adults had higher local reaction rates than children and some vaccines containing larger amounts of viral antigen induced significantly higher rates of reactivity than did vaccines containing smaller amounts of antigen. Although 37-51% of all recipients experienced either a local and/or febrile reaction to influenza immunization, the reactions were in general mild and would not consitute a significant disadvantage in the immunization of children over 6 years and adults to prevent influenza infection and its sequelae.

This paper provides an overview of Bellcore's activities in the area of nationally compatible, customer controllable, DS3 rate (45 Mb/s), multipoint, digital networks for distribution to and collection from affiliates of broadcast quality NTSC television on terrestrial digital fiber optic and microwave interoffice transmission facilities (more than 215 cities are now interconnected) in a manner which rivals today's domestic satellite networks in performance, reliability, flexibility and security. It also outlines a three year work program leading toward a multi-carrier, multi-supplier, multi-broadcaster trial of such a network.