International Journal for Research in Applied Science & Engineering Technology (IJRASET)
ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor: 7.177
Volume 7 Issue V, May 2019- Available at www.ijraset.com
© IJRASET: All Rights are Reserved Page 847
Dimensional Analysis for Determining Optimal
Discharge and Penstock Diameter in Reaction
Turbines
Pradip B. Nemane
1
, Mahendra N. Umare
2
1
M.Tech Student,
2
Ass Professor, Department of Civil Engineering, K.D.K. College of Engineering, Nagpur-440009, India
Abstract: The objective is to analyze the penstock diameter and discharge dimensionally to get optimization of dimensions of
penstock and discharge through it. This dimensional analysis will give the general insights to minimize the consumption of
water while producing hydro electric power. The analysis mainly based on the penstock’s geometric and hydraulic
characteristics, hydraulic head, and the desired power production. Minimizing water consumption for energy production may be
effective to the availability of water for other purposes such as irrigation and navigation. The analysis in this paper carried out
from various dimensionless relationships between power production, flow discharge, and head losses which were derived
previously by various authors. As mentioned in the analysis it was found that for minimizing water consumption, the ratio of
head loss to gross head should remained not more than 15.6%. Taking into consideration various dimensional constants and
friction factors the formulation in analysis is explained. Making iterative calculations based on derivation given by different
authors the maximum and optimum diameter as well as optimum discharge with respect to head loss is calculated. An example
of application on an existing 2x12 MW Hydro Power Project is presented for determining optimal flow discharge and optimal
penstock diameter for reaction turbine by dimensional analysis.
Keywords: Hydropower, penstock, optimal flow, gross head, dimensional analysis, gross head, turbine.
I. INTRODUCTION
India's economically exploitable and viable hydroelectric potential is estimated to be 148,701 MW. An additional 6,780 MW from
smaller hydro schemes (with capacities of less than 25 MW) is estimated as exploitable. 56 sites for pumped storage schemes with
an aggregate installed capacity of 94,000 MW have also been identified. In central India, the hydroelectric power potential from the
Godavari, Mahanadi, Nagavali, Vamsadhara and Narmada river basins has not been developed on a major scale due to potential
opposition from the tribal population. .As per report from ‘World Energy Council’ the hydropower capacity is often categorized as
‘gross theoretical capacity’, the capacity of hydropower generation possible if all natural water flows contained as many 100%
efficient turbines as possible; ‘technically exploitable capacity’, the amount of gross theoretical capacity possible within the limits
of current technology; and ‘economically exploitable capacity’, the capacity possible within the constraints of current technology
and local economic conditions. There are three types of hydropower stations: ‘run of river’, where the electricity is generated
through the flow of a river’; ‘reservoir’, where power is generated through the release of stored water; and ‘pumped storage’, where
stored water is recycled by pumping it back up to a higher reservoir in order to be released again. Hydropower facilities installed
today range in size from less than 100 kW to greater than 22 GW, with individual turbines reaching 1000 MW in capacity.
The public sector accounts for 92.5% of India's hydroelectric power production. The private sector is also expected to grow with the
development of hydroelectric energy in the Himalayan mountain ranges and in the northeast of India. The hydropower generation is
highly capital-intensive mode of electricity generation but being renewable source of energy with no consumables involved; there is
very little recurring cost and hence no high long term expenditure. It is cheaper as compared to electricity generated from coal and
gas fired plants. The life cycle analysis of hydropower shows as cleanest electricity technology with a low carbon footprint,
excellent energy pay back ratio, feasible for mass storage of electricity and an opportunity for development when social and
environmental impacts are dealt with properly. Also hydropower plays a key role in power systems due to its flexibility and
reliability and in the present scenario; its importance has further increased because of the large scale addition of variable renewable
energy power in the form of solar and wind energy in the power system. The projects have potential to meet power requirements of
remote and isolated areas. These factors make small hydel as one of the most attractive renewable source of grid quality power
generation. Apart from the benefit of increase in installation of power generation in the state and eventually overall capacity
addition in the country, there is a series of socio-economic activities in the project area which help in overall development of the
area, by providing sustainable economic activity, employment opportunity and inherent potential of developing entrepreneurs.