الفهرس 
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Abstract
SUMMARY In this work, the problem of dry area formation during vacuum infusion is studied. In particular the effect of dry area repair by re-infusion on the tensile properties of the composite material is investigated. The work presented a comparison between repaired (re-infused) and unrepaired (Intact) samples produced by VARI. The ultimate tensile strengths (UTS) were measured and the failure modes were observed for the two cases. It was concluded that re-infusion has a minor effect on the ultimate tensile strength especially when the parent and repair laminates have almost the same quality. A methodology using finite element analysis program ”PAM-RTM” was presented to prevent the occurrence of dry areas during VARI. A 25 m long wind turbine blade is taken as a case study. It was concluded that seven feeding lines can fill the blade before resin starts to cure so that no dry areas would result The thesis is organized as follows. Chapter One, provides an overview to the problem of dry area formation. Chapter Two presents an overview of the up to date research in composite manufacturing processes especially VARI process and repair techniques applied to dry areas. Chapter Three illustrates the experimental work including the material used and the manufacturing procedure for intact and re-infused specimens that are used to perform tensile tests. Chapter Four presents the results and discussions of the performed tensile tests. Chapter Five explores the reasons behind dry area formation and how to avoid it using finite element simulations. Chapter Six presents the conclusions of this work, future work and recommendations