SAE J2601 Key Modeling Assumptions 07

7. KEY MODELING ASSUMPTIONS

Thermodynamic modeling was used to develop the table-based fueling protocol and several assumptions were made based upon feedback from the station and vehicle manufacturers. This section and Appendix A (Tables A2 and A3) contain these assumptions. If the vehicle parameters are outside these bounds (see Appendix A), then the CHSS should be validated with respect to the standard protocols (and non-standard protocols, if applied) to ensure that CHSS operating boundaries are not violated and that there are no performance or other concerns.

7.1 Reference Conditions

In developing these protocols, the maximum total reference pressure drop from break-away to CHSS (see Appendix A) has been assumed under the following reference conditions: CHSS pressure of 10 MPa, and a fuel temperature of -15 °C at the break-away.

7.2 Vehicle and Station Dispenser Assumptions

The vehicle reference pressure drop is 20 MPa from receptacle to CHSS and the station dispenser reference pressure drop is 15 MPa from the break-away to the nozzle exit (combined total pressure drop of 35 MPa) at a mass flow 1.5 times the average mass flow required to fuel the entire storage capacity in 3 minutes; e.g., for a capacity of 5 kg: mass flow = 5000 g/180 s * 1.5 = 41.67 g/s.