Flow Distribution Control Characteristics in Marine Gas Turbine Waste- Heat Recovery Systems. Phase 2. Flow Distribution Control in Waste-Heat Steam Generators

This technical report is concerned with the effect of flow distribution control on the design and performance of marine gas turbine waste- heat steam generators. Major design requirements and critical problems associated with a waste-heat steam generator were reviewed, and an existing two- dimensional heat exchanger model based on the compact heat exchanger design criteria and the relaxation approach was modified and updated to estimate the waste-heat steam generator performance at any inlet gas flow distribution. Performance estimates were made of the steam generator using a uniform velocity distribution, and also actual flow distribution data available at the diffuser inlet with and without flow distribution controls, all at design and off design operating conditions of the gas turbine engine. Results of the study indicate that the exit steam temperature of the baseline waste-heat steam generator with and without flow distribution controls would be 725 F and 450 F, respectively, for a constant design flow rate of 7.9 lbsec, and for a constant exit temperature of 700 F, the water flow rates would be 8.1 lbsec and 6.6 lbsec, respectively. A suggested experimental program to provide information for comparison with the analytical results, and to obtain applicable operational experience is also described in this report.