Common use of Interface between test object and test environment Clause in Contracts

Interface between test object and test environment. Figure 4 and Figure 5 show the physical interfaces between the SOC cell / SOC stack test object and the test environment. The physical interfaces between the test environment (test station) and the SOC cell/stack test object can be separated in media, electric, heat and mechanic interfaces. Media interfaces are the reactants inlet and outlet; electric interfaces are the load and power supply and voltage wiring; heat interface is the oven and the mechanic interface is to mount the cell/stack on the test station which may supply compression force to the cell/stack. These interfaces will be defined by different physical parameters. Depending on the test program these physical parameters can be either of input nature (TIP) or of output nature (TOP) (see Table 1). Test environment TTP A Test Object: Cell V TBP negative electrode gas out VCell TOven Test environment Test object: SOC Stack V V A V V negative electrode gas out TBP TTP TOven For the reactants at cell/stack inlet and/or outlet these parameters are:  Temperature,T  Flow (mass or volume),f  Pressure,p  Gas composition,x The electric interface parameters are:  Cell/stack current (common synonym is stack load), I  Stack voltage, Vstack  Voltages of cell or the individual repeating units, Vcell or VRU,i The heat interface parameters are:  Oven temperature, Toven  Stack top plate temperature, TTP  Stack bottom plate temperature, TBP  Cell or stack internal temperature Tcell or Tstack,intern Considering the fact that a temperature gradient in the stack is unavoidable and depends on various factors such as gas flow rates, current, thermal exchange rate with the furnace, it is difficult to determine the stack temperature. In practice, depending on the stack design, temperature sensors mounted at different locations in or around the stack (e.g., in endplates, in gas inlet/outlet channels, or just in close proximity to the stack) can be used to estimate the stack temperature. It is however important to identify the one that represents the best the real stack temperature. In order to make results comparable among different test facilities, it is necessary to agree prior to the test on which temperature is used to represent the stack temperature. For the results presentation, it is recommended to show also other temperatures measured in order to obtain information on the temperature distribution in the stack. The mechanic interface parameter is:  Cell or stack compression force, Fcompr Ideally, the positions for the setting/monitoring of the input/output parameters are as close as possible to the boundary of the test object and the test environment. Chapter 7 shows the recommended nomenclature to describe the parameters that are recommended to be measured and/or calculated.

Interface between test object and test environment. Figure 4 and Figure 5 show the physical interfaces between the SOC cell / SOC stack test object and the test environment. The physical interfaces between the test environment (test station) and the SOC cell/stack test object can be separated in media, electric, heat and mechanic interfaces. Media interfaces are the reactants inlet and outlet; electric interfaces are the load and power supply and voltage wiring; heat interface is the oven and the mechanic interface is to mount the cell/stack on the test station which may supply compression force to the cell/stack. These interfaces will be defined by different physical parameters. Depending on the test program these physical parameters can be either of input nature (TIP) or of output nature (TOP) (see Table 1). Test environment TTP A Test Object: Cell V TBP negative electrode gas out VCell TOven Test environment TTP Test object: SOC Stack V V A V V TBP negative electrode gas out TBP TTP V1 V2 VN TOven For the reactants at cell/stack inlet and/or outlet these parameters are:  ▪ Temperature,T  ▪ Flow (mass or volume),f  ▪ Pressure,p  ▪ Gas composition,x The electric interface parameters are:  ▪ Cell/stack current (common synonym is stack load), I  ▪ Stack voltage, Vstack  ▪ Voltages of cell or the individual repeating units, Vcell or VRU,i The heat interface parameters are:  ▪ Oven temperature, Toven  ▪ Stack top plate temperature, TTP  ▪ Stack bottom plate temperature, TBP  ▪ Cell or stack internal temperature Tcell or Tstack,intern Considering the fact that a temperature gradient in the stack is unavoidable and depends on various factors such as gas flow rates, current, thermal exchange rate with the furnace, it is difficult to determine the stack temperature. In practice, depending on the stack design, temperature sensors mounted at different locations in or around the stack (e.g., in endplates, in gas inlet/outlet channels, or just in close proximity to the stack) can be used to estimate the stack temperature. It is however important to identify the one that represents the best the real stack temperature. In order to make results comparable among different test facilities, it is necessary to agree prior to the test on which temperature is used to represent the stack temperature. For the results presentation, it is recommended to show also other temperatures measured in order to obtain information on the temperature distribution in the stack. The mechanic interface parameter is:  ▪ Cell or stack compression force, Fcompr Ideally, the positions for the setting/monitoring of the input/output parameters are as close as possible to the boundary of the test object and the test environment. Chapter 7 shows the recommended nomenclature to describe the parameters that are recommended to be measured and/or calculated.