TABLE OF CONTENTS Natural gas is often found in places where there is no local market, such as in the many offshore fields around the world. For natural gas to be available to the market, it must be gathered, processed, and transported. Quite often, collected natural gas (raw gas) must be transported over a substantial distance in pipelines of different sizes. These pipelines vary in length between hundreds of feet to hundreds of miles, across undulating terrain with varying temperature conditions. Liquid condensation in pipelines commonly occurs because of the multicomponent nature of the transmitted natural gas and its associated phase behavior to the inevitable temperature and pressure changes that occur along the pipeline. Condensation subjects the raw gas transmission pipeline to two-phase, gas/condensate, flow transport. Hence, a better understanding of the flow characteristics is needed for the proper design and operation of pipelines. The problem of optimal design of such pipelines becomes accentuated for offshore gas fields, where space is limited and processing often is kept to a minimum; therefore, total production has to be transported via multiphase pipelines. These lines lie at the bottom of the ocean in horizontal and near-horizontal positions and may contain a three-phase mixture of hydrocarbon condensate, water (occurring naturally in the reservoir), and natural gas flowing through them.
Multiphase transportation technology has become increasingly important for developing marginal fields, where the trend is to economically transport unprocessed well fluids via existing infrastructures, maximizing the rate of return and minimizing both capital expenditure (CAPEX) and...
