Data (Post) Processing Clause Samples

Data (Post) Processing. Here, the post processing of the test results (TIPs and TOPs) shall be described. When reporting, the significant figures of a test variable should be consistent with its measurement uncertainty. For a calculated test variable, the lesser number of significant figures of all of the involved test variables should determine the significant figure. The standard deviation (stdev), relative standard deviation (RSD) and standard error (stderr) should be expressed with at least one additional figure. The RSD should be reported with two significant figures. i zi Electrochemical reaction H2 2 H2 + O2-🡪 H2O + 2e- CO 2 CO + O2-🡪 CO2 + 2e- CH4 8 CH4 + 4O2-🡪 CO2 + 2H2O + 8e- CpHqOr 4p+q-2r CpHqOr + (2p+q/2-r)O2-🡪 pCO2 + q/2H2O + (4p+q-2r)e- O2 4 O2 + 4e-🡪 2O2- H2O 2 H2O + 2e-🡪 H2 + O2- Faraday constant F = 96485.3 C mol-1 = 96485.3 A s mol-1 Oxygen fraction in air xO2 = 0.2095 Lower heating[7] value (LHV) of H2 LHVH2 = 119.93 kJ g-1 = 241.77 kJ mol-1 Higher heating[7] value (HHV) of H2 HHVH2 = 141.86 kJ g-1 = 285.98 kJ mol-1 Voltage equivalent to LHV of H2 LHVH2 / (2F) = 1.253 V Voltage equivalent to HHV of H2 HHVH2 / (2F) = 1.482 V Molar gas constant R = 8.31446 J K-1 mol-1 Normal temperature Tn = 273.15 K Normal pressure Pn= 101325 N m-2 = 101325 Pa Molar volume of an ideal gas at normal temperature and pressure 3 -1 -1 Vm = RTn/Pn = 8.31446 x 273.15 / 101325 mn mol = 22.414 ln mol Number of electrons transferred when one molecule of reactant component i is electrochemically reacted (zi) Gas utilization (Ugas) Number of repeating units in the stack: N Flow rate of reactant component i (i = 1 … n) in the negative/positive electrode of the stack: fi,in(nlpm) Theoretical current (Itheory) assuming 100% gas utilization (all reactant gas is consumed through electrochemical reactions): 𝐹 ∑𝑛 1 𝑧𝑖 × 𝑓𝑖,𝑖𝑛 96485.3 ∑𝑛 1 𝑧𝑖 × 𝑓𝑖,𝑖𝑛 𝐼𝑡ℎ𝑒𝑜𝑟𝑦 = ∙ 𝑖= = × 𝑖= 𝑉𝑚 × 60 𝑁 22.414 × 60 𝑁 ∑𝑛 1 𝑧𝑖 × 𝑓𝑖,𝑖𝑛 = 71.74 × 𝑖=𝑁 gas utilization at current I: 𝑈 = 𝐼 × 100%= 𝐼×𝑁 × 100% 𝑔𝑎𝑠 𝐼𝑡ℎ𝑒𝑜𝑟𝑦 71.74×∑𝑛 𝑧𝑖×𝑓𝑖,𝑖𝑛𝑖=1 Nernst voltage / reversible (thermodynamic) voltage / theoretical open circuit voltage (VN) 𝑅𝑇 𝑝𝑂2,𝑝𝑜𝑠 𝑉𝑁 = 4𝐹 𝑙𝑛 𝑝 (considering SOC as an oxygen concentration cell) 𝑂2,𝑛𝑒𝑔 𝑟 𝑉 = | ∆ 𝐺(𝑇,𝑝) | (for any reaction) 𝑁 𝑧𝐹 ∆𝑟𝐺(𝑇, 𝑝): ▇▇▇▇▇ free enthalpy of reaction as a function of temperature and pressure. For the reaction: H2 + 0.5 O2 = H2O1 𝑝2 𝑝𝐻2,𝑛𝑒𝑔 ∆𝑟𝐺(𝑇, 𝑝) = ∆𝑟𝐺0(𝑇) − 𝑅𝑇𝑙𝑛 𝑂2,𝑝𝑜𝑠 𝑝𝐻2𝑂,𝑛𝑒𝑔 1 ∆𝑟𝐺(𝑇, 𝑝) ∆𝑟𝐺0(𝑇) 𝑅𝑇 𝑝2 𝑝𝐻2,𝑛𝑒𝑔 �� = − = − + 𝑙𝑛 𝑂2,𝑝𝑜𝑠 𝑁 2𝐹 2𝐹 2𝐹 𝑝𝐻2𝑂,𝑛𝑒𝑔1 𝑅𝑇 𝑝2 𝑝𝐻2,𝑛𝑒𝑔 = 𝑉0(𝑇) + ...