Optimization of Commercial Aircraft Using Battery-Based Voltaic-Joule/Brayton Propulsion

Abstract

The intent of this investigation was to survey the potential and establish an array of technical targets for future aircraft employing hybrid-electric battery-based voltaic-Joule/Brayton motive power systems with no additional electrical energy drawn from generators mechanically coupled to gas turbines. Irrespective of passenger accommodation (that is, 70 or 180 passengers), it was concluded that the trifan morphology (two underwing podded gas turbines and one aft-fuselage-mounted electrically driven motor) would be an appropriate choice. Although a battery cell-level gravimetric specific energy (referred to as “battery energy density”) of at least 1300  (W·h)/kg would be desirable, a less ambitious, yet still aggressive, target of 900–950  (W·h)/kg for battery energy density was found to yield a worthwhile outcome. In terms of effecting a 15% block fuel reduction compared to a suitably projected gas-turbine-only year-2035 aircraft and, in keeping with the aforementioned technical recommendations design r...