Duct fittings are a construction term in ventilation and air conditioning engineering, referring to functional connecting components used in duct systems. These mainly include bends, tees, crosses, reducers, shaped pipes, guide vanes, and flanges. The pressure loss data for duct fittings provided by ASHRAE and CIBSE suffers from insufficient accuracy. Research indicates that using a k-ε turbulence model combined with a QUICK higher-order scheme can control the relative error of pressure loss prediction to within 10%, and the computational domain setting is optimized through grid dependency testing.
The industry development analysis employs quantitative methods such as trend forecasting and causal forecasting, as well as qualitative methods such as buyer intent surveys and the Delphi expert opinion method. The current situation study uses SCP theory to analyze market structure, behavior, and performance, combines Porter's Five Forces model to assess the industry competitive landscape, and analyzes the macro-environmental impacts through PEST theory.
