Intermediate Thermal Drying Velocity Profiles for Polyester Cotton Blends
Symmetric nozzle velocity between 18 and 22 m/s during intermediate drying prevents dye migration and maintains shade uniformity in polyester cotton blends.
Slotted Nozzle Array
Airflow Distribution
Mechanical configuration of parallel vents in a dryer plenum distributes high velocity air evenly across a moving fabric web. In modern textile stenters, a slotted nozzle array delivers uniform thermal energy by discharging heated gas perpendicular to the textile path. This arrangement ensures that the entire width of the fabric receives identical convective drying conditions.
Physical Layout
Arrangement of these openings determines the pattern of heat and mass transfer across the textile. In a typical slotted nozzle array, alternating slots are spaced at calculated intervals to allow exhaust air to escape without disrupting the incoming jets. This geometry maintains a high heat transfer rate while preventing air turbulence from destabilizing the running fabric.
Performance Advantage
Uniform distribution of air prevents localized over-drying and dye migration across the web. When processing wide-width home textiles, using a slotted nozzle array maintains a flat fabric profile and prevents the formation of wavy selvages. This feature is particularly valuable for fabrics that are highly sensitive to uneven heat distribution, as it guarantees that both sides of the fabric dry at the exact same rate without causing skew or bow.
Operational Limit
Lint accumulation in the narrow slots can block the airflow, leading to cold spots. Regular cleaning and maintenance are required to keep the pressure balanced across the plenum. This operational requirement is necessary to ensure consistent drying performance.