Bianchi-V cosmological models with viscous fluid and constant deceleration parameter in general relativity

In this paper we discuss the variation law for Hubble's parameter, average scale factor in spatially homogenous anisotropic Bianchi Type V space-time that yields a constant value deceleration parameter. Using the law of variation for Hubble's parameter, exact solutions of Einstein's field equations are obtained for Bianchi-V space time filled with viscous fluid in two different cases where the universe exhibits power law and exponential expansion. We investigate a number of solutions with constant and time varying cosmological constant together with variable and constant bulk viscosity. We find that the constant value of deceleration parameter is reasonable for the present day universe and gives an appropriate discussion of evolution of universe with the recent observations of type Ia supernovae. The detailed study of physical and kinematical properties of the model is also discussed.