Renormalized viscosity, renormalized resistivity, and various energy fluxesare calculated for helical magnetohydrodynamics using perturbative fieldtheory. The calculation is to first-order in perturbation. Kinetic and magnetichelicities do not affect the renormalized parameters, but they induce aninverse cascade of magnetic energy. The sources for the the large-scalemagnetic field have been shown to be (1) energy flux from large-scale velocityfield to large-scale magnetic field arising due to nonhelical interactions, and(2) inverse energy flux of magnetic energy caused by helical interactions.Based on our flux results, a premitive model for galactic dynamo has beenconstructed. Our calculations yields dynamo time-scale for a typical galaxy tobe of the order of $10^8$ years. Our field-theoretic calculations also revealthat the flux of magnetic helicity is backward, consistent with the earlierobservations based on absolute equilibrium theory.
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