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A new thermal insulation microactuator for Braille display using a phase change material (PCM) composite with induction heating is proposed. The PCM composite is prepared by fully mixing paraffin with multi-walled carbon nanotubes (MWCNTs), which is mainly used as both electrically and thermally conductive enhancer. As a result of that, the PCM composite is conductive and a wireless induction heating can be realized with the paraffin composite, which avoids the connection of wires from the inner chamber with a relatively simple fabrication process. In order to prevent the penetration of the paraffin from the elastic film, a solvent-resistant TPU diaphragm is adopted to seal the PCM chamber. In addition, thermal insulation between the higher temperature of PCM and the finger contact is designed by adding the PDMS diaphragm with PDMS pins. When the input power is 1.29W at AC frequency of 1kHz, the actuation height of the Braille dot reaches 259$\mu$m within 7s. The microactuator for Braille display presented in this paper has the advantages of short response time, thermal isolation, simple fabrication, small size and low cost.

The current development of global warming and CO₂ emission problems cannot be overlooked. Thus, global scale measures of efforts are becoming crucial. Thermal properties of insulation materials need to be considered as high performance thermal insulation systems are crucial for efficient energy saving. The most important parameter as indicator of a thermal insulation material is the effective thermal conductivity, but elements that affect the thermal insulation performance are rather complicated. Generally, conduction and radiation heat transfer are needed to be separately considered in precisely evaluating the thermal insulation performance as they coexist in the heat transfer process inside a multilayer insulation system. In this paper, numerical analysis of a complete diffusive enclosure model as a thermal insulation is observed to investigate the radiation effects by its dispersive heat transfer mechanisms. View factor of each relatively large dispersed material is derived in the enclosure model, where it is applicable to various shapes and any particular arrangements of dispersed materials. As this paper is the first part of a three-part working research paper, numerical analysis in this paper is carried out by assuming that the medium within the space inside the insulation system is taken to be nonparticipating, therefore conduction and convection effects during the heat exchange are negligible. This paper will be continued with application of the numerical analysis in observing radiation heating effects by wall-ceiling integration towards indoor environment and radiation–conduction heat transfer mechanisms in one-dimensional multilayer insulation system.

As the demand for low-energy buildings keeps rising, there is a need to develop highly efficient insulation materials to be applied in building envelopes. Preferably, such materials should have low U-values (overall heat transfer coefficients) to reduce energy consumption through heat loss. One such material is a vacuum insulation panel (VIP). With U-values being several times lower than that of traditional insulation, VIPs offer not only an excellent capacity to reduce building heat losses but also increase living space due to reduced requirements for insulation thickness. Thus, the purpose of this paper is to study the economic feasibility of improving U-values of external walls with traditional and advanced insulation materials. The analysis is based on Level 6 of the Code of Sustainable Homes (CSH), while an external wall (in Nottingham) with a U-value of 0.17 W/m²K was chosen as a case study.

Nanocellulose is a renewable and biocompatible nanomaterial with a high strength, low density, and tunable surface chemistry. Since a lot of hydroxyl groups are present on the surface of the nanocellulose, this gives them various surface chemistries that can be tailor-made for specific application. This unique property makes them a promising candidate for various applications. Nanocellulose aerogels have gained considerable interest in the scientific community globally due to their renewability, good mechanical properties, low density, high porosity, natural biodegradability, and environmental friendliness. These fascinating properties makes them an attractive material in environmental and engineering applications. This chapter reviews recent attempts to apply nanocellulose aerogels as efficient materials for thermal insulation, flame retardancy, EMI shielding, oil absorption etc.

This research analyzed thermal insulation and noise reduction of an ecological module material by experimental methods. Ecological module materials were placed on the roof without insulation to measure its effect of thermal insulation in summer. Under the indoor air-conditioned environment, it can reduce 53% of heat transfer on roof and lower the electricity consumption of air-conditioning by 0.08 kWh·d⁻¹·m⁻². Meanwhile, its equivalent thermal resistance can be up to 0.53 m².K·W^-1. In the laboratory, reverberation chamber method was adopted to measure the acoustical absorption coefficient of this ecological module material. It showed that the coefficient can reach 0.8 during the range of medium frequency and the average coefficient was 0.52.