In order to manufacture smaller and more efficient electric motors an accurate prediction of the motor thermal performances at the design stage is a necessity. In addition, the thermal performance often needs to be analyzed when a motor is used in a different way to which it was originally designed for. An important example is the use of variable speed drives with induction motors designed for ...

The benefits of rooftop greening are ascertained in thermal perspective. It effectively reduces the near surface ambient temperature and the reflected irradiation from the rooftop slab, thus increasing the thermal comfort environment above the lawn and reduces the heat transferred through the rooftop slab. The former effect enables the potential usage of the rooftop spaces for human activity an...

This paper presents an analysis of the performance of a pancake absorber with a helical heal exchanger for use with point focus solar concentrating collectors. Th e principal difference between this type of absorber and most other concentrating solar collector absorbers is that the intensity of concentrated radiation monotonically increases from the inlet to the outlet of the heat exchanger tub...

Solar water heating (SWH) systems are gaining popularity in ASEAN in the midst of increasing number of affluent population in society and environmental concerns from seemingly unchanged reliance on fossil-based fuels. The penetration of these systems and technologies into ASEAN markets is a welcome development; however there is a need for the method of assessment of their thermal performances. ...

Carbon fiber-reinforced multi-layered pyrocarbon-silicon carbide matrix (C/C-SiC) composites are widely used in aerospace structures. The complicated spatial architecture and material heterogeneity of C/C-SiC composites constitute the challenge for tailoring their properties. Thus, discovering the intrinsic relations between the properties and the microstructures and sequentially optimizing the...

In this paper, the heat transfer performances of aluminum metal foams, placed on horizontal plane surface, was evaluated in forced convection conditions. Three different types of contacts between the sample and the heated base plate have been investigated: simple contact, brazed contact and grease paste contact. First, in order to perform the study, an ad hoc experimental set-up was built. Seco...

We report the main characteristics and performances of the first – to our knowledge – prototype of an ultra-stable cavity designed and produced by industry with the aim of space missions. The cavity is a 100 mm long cylinder rigidly held at its midplane by an engineered mechanical interface providing an efficient decoupling from thermal and vibration perturbations. The spacer is made from Ultra...