The present study aims to analyzse alternative passive design solutions for enhancing building energy and hygrothermal efficiency in the Sahelian zone.To achieve this,a model representing a standard single-storey ceme...The present study aims to analyzse alternative passive design solutions for enhancing building energy and hygrothermal efficiency in the Sahelian zone.To achieve this,a model representing a standard single-storey cementhollow block dwelling building and its relevant parameters was input into EnergyPlus,combined with OpenStudio or SketchUp.Scenarios were then analyzed to evaluate the effects of roof solar reflectivity,wall external insulation,natural ventilation,and their combined options.First,the base case,serving as a reference model,was validated using measured and simulated temperatures by calculating the scientific criteria,such as the NBME and CVRMSE coefficients recommended by the ASHRAE and IPVM standards.Additionally,the numerical simulation was used to compare interior temperatures,discomfort hours,thermal parameters,and the hygrothermal index(IHT)across seven cases studied.The reference model simulation indicated that cement-based hollow blocks are less effective for building envelopes in the Sahelian climate,with 51.48%discomfort hours and an IHT of 1.6,as shown in the Givoni diagram.The results revealed that the wall external insulation was the most effective passive solution,with 56%of comfort hours and an IHT of 0.7,which indicates the expected position of the model within the hygrothermal comfort zone of the Sahelian climate.Combining passive strategies yields the best scenario,resulting in a 28.25%reduction in annual total discomfort hours compared to the base case.These simulations demonstrated the effectiveness of accessible passive design solutions applicable in dwelling construction for the sustainable development of countries in the Sahelian climate.展开更多
Recently, the high-brightness LEDs have begun to be designed for illumination application. The increased electrical currents used to drive LEDs lead to thermal issues. Thermal management for LED module is a key design...Recently, the high-brightness LEDs have begun to be designed for illumination application. The increased electrical currents used to drive LEDs lead to thermal issues. Thermal management for LED module is a key design parameter as high operation temperature directly affects their maximum light output, quality, reliability and life time. In this review, only passive thermal solutions used on LED module will be studied. Moreover, new thermal interface materials and passive thermal solutions applied on electronic equipments are discussed which have high potential to enhance the thermal performance of LED Module.展开更多
文摘The present study aims to analyzse alternative passive design solutions for enhancing building energy and hygrothermal efficiency in the Sahelian zone.To achieve this,a model representing a standard single-storey cementhollow block dwelling building and its relevant parameters was input into EnergyPlus,combined with OpenStudio or SketchUp.Scenarios were then analyzed to evaluate the effects of roof solar reflectivity,wall external insulation,natural ventilation,and their combined options.First,the base case,serving as a reference model,was validated using measured and simulated temperatures by calculating the scientific criteria,such as the NBME and CVRMSE coefficients recommended by the ASHRAE and IPVM standards.Additionally,the numerical simulation was used to compare interior temperatures,discomfort hours,thermal parameters,and the hygrothermal index(IHT)across seven cases studied.The reference model simulation indicated that cement-based hollow blocks are less effective for building envelopes in the Sahelian climate,with 51.48%discomfort hours and an IHT of 1.6,as shown in the Givoni diagram.The results revealed that the wall external insulation was the most effective passive solution,with 56%of comfort hours and an IHT of 0.7,which indicates the expected position of the model within the hygrothermal comfort zone of the Sahelian climate.Combining passive strategies yields the best scenario,resulting in a 28.25%reduction in annual total discomfort hours compared to the base case.These simulations demonstrated the effectiveness of accessible passive design solutions applicable in dwelling construction for the sustainable development of countries in the Sahelian climate.
基金the support by Consumerizing Solid State Lighting(CSSL)
文摘Recently, the high-brightness LEDs have begun to be designed for illumination application. The increased electrical currents used to drive LEDs lead to thermal issues. Thermal management for LED module is a key design parameter as high operation temperature directly affects their maximum light output, quality, reliability and life time. In this review, only passive thermal solutions used on LED module will be studied. Moreover, new thermal interface materials and passive thermal solutions applied on electronic equipments are discussed which have high potential to enhance the thermal performance of LED Module.
