The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
BACKGROUND Tubular photobioreactors are being considered for growing microalgae to produce renewable fuel oils via photosynthesis. Such bioreactors need to be highly energy efficient, or the energy captured in the fuel oil through photosynthesis will barely compensate for the fossil energy required to operate the photobioreactor.
RESULTSComputational fluid dynamics (CFD) modeling of the flow in a conventional tubular loop photobioreactor is used to reveal the existence of substantial dead zones in the typically used U‐bends and 90° elbows. Fluid circulation in these dead zones leads to increased energy consumption, formation of deposits, wall growth and potentially reduced productivity. Alternative designs of U‐bends and 90° elbows are evaluated by CFD modeling. Optimal design of a U‐bend and a 90° elbow are identified and shown to substantially reduce the development of dead zones. Use of the proposed new configurations of bends is shown to reduce the energy consumption for fluid circulation in the loop by up to 15% relative to a conventionally designed tubular loop photobioreactor, for turbulent flow of seawater....