Cfd modelling of h-darrieus vertical axis wind turbine

CHAPTER 2: LITERATURE REVIEW 
The researches and industries are working on the rotor design optimization of VAWT to improve its 
performance. VAWT has some application-based advantages over the HAWT. Liu, Lin, and Zhang 
[17] have reviewed the commercial viability of VAWT. [18]. MacPhee and Beyene [18] focused on 
the Darrieus and Savonius rotors and worked on an extensive research on the latest works of the 
design of rotor and testing until the year 2012. Their work also reflects the advantage of VAWT in 
off grid and small scale applications. But for design optimization works, many parameters are there 
to consider, and experimentation is not always feasible. As a result, simulations are getting more 
importance and many researchers have worked on improving the simulation of VAWT. Ghasemian, 
Ashrafi, and Sedaghat [19]
have reviewed the various CFD techniques of simulation for Darrieus 
VAWT. 
However, it is very important to do some sort of validation before this simulation results can be 
trusted. Bedon et al. [20] have reviewed many databases of aerodynamic coefficients that are used 
for VAWT simulations. The comparison with the simulation results demonstrated considerable 
discrepancy so practical general considerations are recommended to the designers before deciding 
on the reliability of the simulations. So, careful validation remains a demanding step for simulation 
of VAWT. 
Another approach is the analytical approach which can be very challenging, strenuous and 
extremely complicated. Mohammed et al. [21] have summarized and reviewed different momentum 
models. The momentum models include the double multiple streamtube (DMST) model, multiple 
streamtube model (MST) and single streamtube model (SST). Models other than momentum models 
include the vortex model and cascade model. [22] 
The power coefficient of vertical axis wind turbines can be optimized using the tip speed ratio. [23]. 
Aslam Bhutta et al. [23] have reviewed the various design techniques and configurations of the 
vertical axis wind turbines. They studied different configurations of vertical axis wind turbines like 
the Darrieus rotors, Savonius rotors, combined Darrieus and Savonius rotors, Sistan wind mill, 
Zephyr tubine and observed how different power coefficients were obtained. They showed how 
power coefficient can be optimized using the tip speed ratio.
The current study focus on the 2D CFD simulation of a H-Darrieus vertical axis wind turbine where 
the turbulence SST model is chosen as the turbulence model. Validation of the simulation results are 

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also done with experimental result available in the literature.