In this research, the heat transfer coefficient (HTC) and pressure drop of alternating cross-section flattened (ACF) tubes were investigated experimentally compared with same parameters a circular tube. Three different ACF fabricated from copper tubing an internal diameter 4.5 mm, thickness 1 length 400 mm. The twist angles 30, 45, 90°. experimental ranges covered mass flux 729–1,434 kg/m2s 12–...

In a chance constrained program (CCP), decision makers seek the best whose probability of violating uncertainty constraints is within prespecified risk level. As CCP often nonconvex and difficult to solve optimality, much effort has been devoted developing convex inner approximations for CCP, among which conditional value-at-risk ([Formula: see text]) known be more than decade. This paper studi...

Self-extinction plays a crucial role in enabling the safe use of timber structures mid- and high-rise construction, where structural integrity during after fire is critical. To date, influence that oxygen concentration may have conditions lead to self-extinction has not been studied depth. Also, thermal occurred carefully studied. During fires, concentrations will defer from those ambient condi...