ABSTRACT
Traditional gear design approaches provide design parameters that meet only one design requirement at a time. However, a major problem with this kind of approach is the deficit for high consistency and reliability. The objective of the article is to present a multi-objective design optimisation procedure for addendum modified spur gear with altered tooth sum. The design procedure involves implementation of Particle Swarm Optimisation (PSO) and a hybrid PSO- Teaching-learning based optimisation (PSO-TLBO) algorithm for simultaneous optimisation of the weight and contact or hertzian stress along line of action of the spur gear drive. The design optimisation was validated through stress analysis of the optimised spur gear set, using Finite element analysis (FEA) with various mesh types and grain size. Afterwards, manufacturing of the optimised non-standard gear set with metallic (EN24) and a composite (Hylum) gear material using standard tooling. This indicates that with the proposed design optimisation approach there is a possibility of meeting the requirement for efficient, compact, and reliable gear set with reduced computational cost. This study suggests that it is possible to determine a set of optimised design variables that can meet more than one design criteria at a time.
Nomenclature
a | = | Center distance |
Cr | = | Surface reliability factor |
d0 | = | Outside diameter of boss (mm) |
Fs | = | Induced bending load (Lewis formula) |
I | = | Geometry factor |
Kr | = | Bending reliability factor |
L | = | Length of boss (mm) |
Sfe | = | Surface fatigue strength (MPa) |
x | = | Design variable vector gear |
bw | = | Thickness of web (mm) |
Cs | = | Surface factor |
dp | = | Drilled hole diameter (mm) |
Fn | = | Normal load |
J | = | Lewis Geometry factor |
Kms | = | Mean stress factor |
lw | = | Thickness of rim (mm) |
τ | = | Shaft shear strength (MPa) |
y | = | Lewis tooth form factor |
Cl | = | Surface fatigue life factor |
D1&D2 | = | Pitch circle diameter of pinion and gear |
Dr | = | Dedendum circle diameter (mm) |
Fp | = | Wear load (N) |
Ko | = | Over load factor |
Kv | = | Velocity factor |
n | = | Number of drilled holes |
σ | = | Gear material strength (MPa) |
σcomposite | = | Gear material strength (MPa) for composite material |
Cp | = | Elastic coefficient (MPa) |
Di | = | Inside diameter of rim (mm) |
F(x) | = | Objective function |
gi(x) | = | Constraints |
Km | = | Mounting factor |
Kw | = | Load factor |
Sn | = | Standard moore endurance limit |
v | = | Pitch line velocity (m/s) |
Disclosure statement
No potential conflict of interest was reported by the authors.
Data access statement
The data that support the findings of this study are available from the corresponding author [[email protected]] upon reasonable request.