Taguchi Techniques as an Effective Simulation-Based Strategy in the Design of Numerical Simulations to Assess Contact Stress in Gerotor Pumps

Abstract

The contact problem of a trochoidal gear is a drawback and a well-known performance indicator of a gerotor pump. Although numerical simulations aid in the evaluation of contact stress, the difficult task of determining geometrical parameters, operating conditions, and the number of simulations to run falls to the designer. This paper presents the Taguchi techniques as an effective simulation-based strategy to narrow down the geometrical parameter combinations, reducing the solution space and optimizing the number of simulations. The work is first focused on the validation of the proposed numerical model by means of published contact stress results of recognized researchers in the field, as well as the unification of nomenclature and notation. Then, the Taguchi approach is based on a sequence of four experiments, ranging from the screening case with two levels and seven parameters to multiple levels and four parameters with three software input operating conditions (temperature, torque, and friction coefficient) emulating noise effects. The contact stresses of 128 gear sets, having common volumetric capacity and dimensional constraints to detach mechanical performance from flow rate and casing, were analyzed. Results prove the feasibility of the proposed methodology by identifying the most suitable gear set configuration and predicting the quantifiable performances of a real-working gerotor pump.

Aerodynamic Study of MotoGP Motorcycle Flow Redirectors

“…A designer will aim to reduce the time, effort, and costs associated with conducting tests, and numerical simulation can provide advantages in this regard. The application of the Taguchi method in software and computer design has been reported, and Taguchi techniques are demonstrated to be effective simulation-based strategies for narrowing down geometric parameter combinations, reducing solution space, and optimizing the number of simulations [43]. Thus, from the perspective of a designer, the application of the Taguchi method with a numerical simulation technique, such as CFD, helps to reduce the number of test repetitions.…”

“…Main effect plots show how each factor affects the response characteristic (S/N ratio, means, slopes, standard deviations), providing a graphic visualization of the importance of the chosen control parameters. The larger the vertical increment between the two levels and the higher the slope in each factor, the more influential the parameter [43]. In the present study, as the values of C l and C d needed to be as low as possible, the criterion of lower-is-better (LB) was used.…”

Reverse Engineering Used to Profile a Gerotor Pump Rotor

“…Obviously, not only the geometry of the rotor profile has a decisive role in the good operation and efficiency of such hydraulic constructions; the influence of the characteristics of the transported fluids, such as the density of the fluid or the kinematic viscosity, but also the mechanical characteristics and the physical working quantities, such as the flow rate, pressure, or working speed, they also have an extremely important role [25][26][27][28]. To ensure a smooth rotation, the profiles of the inner and outer elements of all gerotors, regardless of the number of lobes, are conjugate to each other, meaning the common normal at all contact points between the two elements passes through a fixed point, thus maintaining a constant angular speed [29].…”