ASME PTC-50-2002 pdf free download.FUEL CELL POWER SYSTEMS PERFORMANCE.
This Code provides test procedures, methods, and definitions for the performance characterization of fuel cell power systems. Fuel cell power systems include all components required in the conversion of input fuel and oxidizer into output electrical and thermal energy. Performance characterization of fuel systems includes evaluating system energy inputs and electrical and thermal outputs to determine fuel- to-electrical energy conversion efficiency and where applicable, the overall thermal effectiveness. These efficiencies will be determined to an absolute uncertainty of less than ±2% at a 95% confidence level. (For example, for a calculated efficiency of 40%, the true value lies between 38% and 42%.)
1.2 SCOPE
This Code applies to all fuel cell power systems regardless of the electrical power output, thermal output, fuel cell type, fuel type, or system application.
Fuel cell power systems contain an assembly of electrochemical cells, which oxidize a fuel to generate direct current electricity. Balance-of-plant subsystems may include controls, thermal management, a fuel processor and a power conditioner. Some fuel cell power systems may contain additional power generating equipment such as steam generators, gas turbine generators, or micro-turl)ine generators. The net power output and all the fuel input to the system shall be taken into account in the performance test calculations.
This Code applies to the performance of overall fuel cell power systems. The Code addresses cornbined heat and power systems, that is, the generation of electricity and usable heat at specific thermal conditions. It does not address the performance of specific subsystems nor does it apply to energy storage systems, such as regenerative fuel cells or batteries. It also does not address emissions, reliability, safety issues, or endurance.
This Code contains methods and procedures for conducting and reporting fuel cell system testing, including instrumentation to be used, testing techniques, and methods for calculating and reporting results.
The Code defines the test 1)oundary for fuel and oxidant input, secondary energy input and net electrical and thermal energy output. At these boundaries, this Code provides procedures for measuring temperature, pressure, input fuel flow and composition, electrical power, and thermal output.
The Code provides procedures for determination of electrical efficiency or heat rate and overall thermal effectiveness at rated or any other steady-state condition. The Code also provides the method to correct results from the test to reference conditions.
1.3 TEST UNCERTAINTY
In accordance with ASME PTC 19.1, procedures are provided for determining the uncertainty associated with the calculated performance parameters of this Code (energy input, electrical energy and thermal outputs, and electrical efficiency or heat rate). In the measurements made to determine performance parameters, there are systematic errors produced by the procedures and instrumentation recommended in this Code. A table of these systematic errors may be found in Section 4 of this Code.
Sample calculations of the uncertainties associated with the system performance parameters, which illustrate the effects of systematic errors and data, are presented in Mandatory Appendix I of this Code.
A pretest uncertainty analysis is recommended. The pretest analysis allows corrective action to be taken prior to the test, which will either decrease the uncertainty to an appropriate level consistent with the overall objective of the test or will reduce the cost of the test while still attaining the test uncertainty.
A post-test uncertainty analysis is mandatory. It will make use of empirical data to determine random measurement errors and test observations to establish whether or not the required uncertainty has been achieved.
This uncertainty procedure serves as a guide for pretest and post-test uncertainty calculations when the Code is used.