Task 8.8 -- Low cost ceramic materials

This subtask was originally titled ``Reheat Combustor Materials`` and was proposed in anticipation of the addition of a reheat combustor to the ICR gas turbine cycle. When the emphasis of ATS became the optimized recuperated cycle, the goal of the subtask was changed to the evaluation of low cost materials for gas turbine combustor liners. It now supplements similar work being conducted by Solar under DOE Contract No.DE-ACO2-92-CE40960, titled ``Ceramic Stationary Gas Turbine (CSGT) Development.`` The use of a ceramic combustor liner in gas turbines contributes to emissions reductions by freeing cooling air for use as primary combustion air and by allowing higher wall temperatures, which contribute to more complete combustion of hydrocarbons. Information from a literature survey, manufacturer`s data, and Solar`s experience was used to select three materials for testing. In addition to material properties requirements for selection, subscale combustor liner cost was required to be at least half of the high modulus continuous fiber reinforced composite part cost. The three materials initially selected for evaluation are listed in Table 1. Four hour subscale rig tests were planned for eight inch diameter liners made from each material. Upon successful completion of each four hour test, a fifty hour test was planned