Propulsion Nozzle Design: bell_optimum
De Laval (converging-diverging) rocket nozzle design parameters — expansion ratio (Ae/At), exit Mach number, pressure ratio (pe/pc), vacuum and optimum thrust coefficient (CF), discharge coefficient (Cd), divergence efficiency (lambda), and Isp correction factor by nozzle type (conical 15-deg, bell 80%, bell optimum/Rao, plug/aerospike, dual-bell) and gamma (1.20/1.25/1.30). Isentropic relations per Sutton & Biblarz RPE 9th Ed; nozzle efficiency corrections per NASA SP-8120.
| nozzle type | record id | Isp correction factor (dimensionless) | discharge coeff cd (dimensionless) | divergence efficiency lambda (dimensionless) | exit mach (dimensionless) | expansion ratio (dimensionless) | gamma ref (dimensionless) | notes | pressure ratio pe pc (dimensionless) | thrust coeff cf opt (dimensionless) | thrust coeff cf vac (dimensionless) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| bell_optimum | bello_er25_g120 | 0.985 | 0.993 | 0.997 | 3.186 | 25 | 1.2 | Rao optimum; exit half-angle ~8 deg; CF_vac=1.9680*0.997*0.993 | 0.01494 | 1.48 | 1.962 |
| bell_optimum | bello_er25_g130 | 0.985 | 0.993 | 0.997 | 3.445 | 25 | 1.3 | Rao optimum; gamma=1.30; CF_vac=1.8694*0.997*0.993 | 0.0119 | 1.378 | 1.865 |
| bell_optimum | bello_er60_g120 | 0.985 | 0.993 | 0.997 | 3.793 | 60 | 1.2 | Rao optimum; SSME-class expansion; CF_vac=2.0107*0.997*0.993 | 0.00475 | 1.53 | 2.006 |
This is a sample. Search the full propulsion nozzle design dataset and 300+ more by creating a free account and accessing the database.
Get started for FREE