Design of Thermally Constrained High-Frequency Induction Heating System

One of the most prominent application areas of induction heating principle is for sealing of caps of plastic and glass containers. It is increasingly being used to seal containers with extremely wide range industrial products. The process ambience around the controller for sealing of bottles containing different types of products could be different. Such prospects, often, could act as constraints for design of power controllers. Dust prone environment prevailing in processes such as for sealing nutraceuticals, coffee, a few pharma products, etc. recommends use of air-tight enclosure. It does not have any ventilation, even the natural air movement inside or the free convection is restricted. This article proposes that the internal convection could still be made effective by creating requisite buoyant force where both power converter topology and component engineering could play important roles. The topology should optimally reduce the power loss and surface temperature of components should be high. The proposed idea has been validated by designing a zero-ventilated 1.5 kW, 50 kHz induction heating system that includes the induction coil head.

Design of Thermally Constrained High-Frequency Induction Heating System

One of the most prominent application areas of induction heating principle is for sealing of caps of plastic and glass containers. It is increasingly being used to seal containers with extremely wide range industrial products. The process ambience around the controller for sealing of bottles containing different types of products could be different. Such prospects, often, could act as constraints for design of power controllers. Dust prone environment prevailing in processes such as for sealing nutraceuticals, coffee, a few pharma products, etc. recommends use of air-tight enclosure. It does not have any ventilation, even the natural air movement inside or the free convection is restricted. This article proposes that the internal convection could still be made effective by creating requisite buoyant force where both power converter topology and component engineering could play important roles. The topology should optimally reduce the power loss and surface temperature of components should be high. The proposed idea has been validated by designing a zero-ventilated 1.5 kW, 50 kHz induction heating system that includes the induction coil head.

Design of Thermally Constrained High-Frequency Induction Heating System

One of the most prominent application areas of induction heating principle is for sealing of caps of plastic and glass containers. It is increasingly being used to seal containers with extremely wide range industrial products. The process ambience around the controller for sealing of bottles containing different types of products could be different. Such prospects, often, could act as constraints for design of power controllers. Dust prone environment prevailing in processes such as for sealing nutraceuticals, coffee, a few pharma products, etc. recommends use of air-tight enclosure. It does not have any ventilation, even the natural air movement inside or the free convection is restricted. This article proposes that the internal convection could still be made effective by creating requisite buoyant force where both power converter topology and component engineering could play important roles. The topology should optimally reduce the power loss and surface temperature of components should be high. The proposed idea has been validated by designing a zero-ventilated 1.5 kW, 50 kHz induction heating system that includes the induction coil head.

Modeling the Evaporation of Drying Sessile Droplets with Buoyancy Driven Internal Convection

Droplet evaporation is a fundamental phenomenon encountered in diverse applications such as inkjet printing, DNA mapping, film coating, and electronics cooling. Modeling the evaporation process of a sessile droplet is complicated because of the coupling of several physical phenomena occurring in different phases and various magnitudes such as the buoyant convection of the liquid in millimeter size droplets and that of the surrounding air/water vapor mixture, in the order of meters. In this study, the theoretical framework presented previously for the steadily fed droplets [Int J Therm Sci, 158 (2020) 106529] is extended to resolve the evaporation of drying droplets with a pinned contact line. Based on the quasi-steady-state assumption, buoyant convection inside the droplet and diffusive-convective transport of vapor in the gas domain are modeled. As a test case, drying process of a water droplet with a 68° initial contact angle on a heated substrate is simulated and the predictions of the model are interpreted.

Effect of Rotational Modulation on Rayleigh – B´enard Convection in a Couple Stress Liquid

The Rayleigh-B´enard convection in a couple stress liquid with rotational modulation is studied using the linear analysis based on normal mode technique. The stability of a horizontal layer of fluid heated from below is examined when, in addition to a steady rotation, a time-periodic sinusoidal perturbation is applied. The expression for Rayleigh number and correction Rayleigh number are obtained using regular perturbation method. The expression for correction Rayleigh number is obtained as a function of frequency of modulation, Taylor number, Couple Stress parameter and Prandtl number. It is observed that rotational modulation leads to delay in onset of convection. Rotation modulation is an example of external control of internal convection.