Page 1 of 16
European Journal of Business &
Social Sciences
Available at https://ejbss.org/
ISSN: 2235-767X
Volume 07 Issue 05
May 2019
Available online: https://ejbss.org/ P a g e | 1224
Optimization of the Francis Turbine to Get the Better Performance and To
Decrease the Vibrational Effects in the Loading Conditions
AUTHOR 1 – Avinash.G, Assistant Professor, Department of Mechanical Engineering,
Pragati Engineering College
AUTHOR 2 – M. Amrutha, Assistant Professor, Department of Mechanical Engineering,
Pragati Engineering College
AUTHOR 3 – M. Sunil Raj, Assistant Professor, Department of Mechanical Engineering,
Pragati Engineering College
Water has a lot of potential to produce electricity with much constant voltage value. Hydro- turbines are usually used to operate at variable load due to different climate nature over the
whole annum. Loadings are the reasons of vibrations which result in failures. In Francis
Turbines loading are due to the fluid pressure and centrifugal force of runner. Problems
failure occurs in different stages like: (1) changes in microstructure; (2) microscopic cracks
formation; (3) microscopic flaws growth (dominant cracks); (4) dominant macro-crack
propagate stably; (5) instability of structure/complete fracture.
In this thesis we are going to design the existing Francis turbine and optimize the design
where the stress and the deflections are high for the existing design and even the material
optimization is being done to get the better outputs. Structural and the modal analysis are
used to get the outputs.
INTRODUCTION
The Francis turbine is a type of water turbine that was developed by James B. Francis in
Lowell, MA. It is an inward-flow reaction turbine that combines radial and axial flow
concepts. Francis turbines are the most common water turbine in use today. They operate in a
head range of ten meters to several hundred meters and are primarily used for electrical
power production. The Francis turbine is a reaction turbine, which means that the working
fluid changes pressure as it moves through the turbine, giving up its energy. A casement is
needed to contain the water flow. The turbine is located between the high-pressure water
source and the low-pressure water exit, usually at the base of a dam. The inlet is spiral
shaped. Guide vanes direct the water tangentially to the turbine wheel, known as a runner.
This radial flow acts on the runner's vanes, causing the runner to spin. The guide vanes (or
wicket gate) may be adjustable to allow efficient turbine operation for a range of water flow
conditions. As the water moves through the runner, its spinning radius decreases, further
acting on the runner. For an analogy, imagine swinging a ball on a string around in a circle; if
the string is pulled short, the ball spins faster due to the conservation of angular momentum.
This property, in addition to the water's pressure, helps Francis and other inward-flow
turbines harness water energy efficiently. Water wheels have been used historically to power
Page 2 of 16
European Journal of Business &
Social Sciences
Available at https://ejbss.org/
ISSN: 2235-767X
Volume 07 Issue 05
May 2019
Available online: https://ejbss.org/ P a g e | 1225
mills of all types, but they are inefficient. Nineteenth-century efficiency improvements of
water turbines allowed them to compete with steam engines (wherever water was available).
In 1826 Benoit Fourneyron developed a high efficiency (80%) outward-flow water turbine.
Water was directed tangentially through the turbine runner, causing it to spin. Jean-Victor
Poncelet designed an inward-flow turbine in about 1820 that used the same principles. S. B.
Howd obtained a U.S. patent in 1838 for a similar design.
EVOLUTION OF THE FRANCIS TURBINE
General speaking, a machine takes energy from a particular form and transforms it into
another form. In a hydraulic machine, the flux which has interchanged energy does not
change its density (and volume) when it is processed by the machine, in comparison to a
thermal machine in which there is variation. This characterisation helps to classify machines,
because the compressibility of the solid, liquid or gas will produce equivalence in terms of
thermal or hydraulic machines. One way to classify machines is by the runner, which is the
most important component of machines and the location of energy exchange. The runner
movement can be rotational and alternative; the change and direction of the absolute value of
the speed is different according to the type of movement. Pumps (generators) and hydraulic
machines (motors) are turbo-machines which behave in a rotational manner. Hydraulic
turbines are strongly related to hydraulic machines, specifically pumps for liquids and gas,
and ventilators, which also maintain a strong relationship to electric machines. Background
Turbines can be classified according to their degree of reaction: when this is null, such as in
the case of a Pelton turbine, the turbine is considered dynamic. Otherwise, if the direction of
the flow is diagonal, this indicates Francis turbine; if it is axial, it is either a Kaplan or Bulb
turbine. Such turbines can regulate flow through their mobile blades.
RADICAL TECHNOLOGICAL CHANGES IN THE TURBINE INDUSTRY
It is not clear if the evolution of the Francis Turbine was interrupted. Its size and potency
after the 1950s suggest a breakthrough in the earlier technology. However, this is not
immediately evident, because once the size and potency of turbines became larger, specific
speed (Ns) did not necessarily change in the period between 1920 and 1990, as shown in Fig.
1. Simultaneously, an alternative analysis might show a much larger increase in turbine
potency and size beginning in the 1960s, associated not only with increased height
exploitation, but also from the perspective of the hydrological dam resource as a whole. This
would suggest new technological changes, since these are not explained by incremental
transformations. Alternatively, changes in other industrial sectors related to the
manufacturing industries and the production of electricity can be considered radical.
Measuring the magnitude of these technological changes implies an association with a set of
variables which in turn enables this qualitative leap. The value of H-Ns reached two peaks:
one in the late 1940s, and another in the early 1980s.
MODELING AND DESIGN OF FRANCIS TURBINE
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European Journal of Business &
Social Sciences
Available at https://ejbss.org/
ISSN: 2235-767X
Volume 07 Issue 05
May 2019
Available online: https://ejbss.org/ P a g e | 1226
Fig. Model of Francis Turbine
Fig. Drafted front view of francis turbine
Fig. Drafted Top View of Francis Turbine
C:\Users\MechLab-69\Pictures\Screenshots\Screenshot (65).png
