Investigation of the Impact of a Particle Foam Insulation on Airflow, Temperature Distribution, Pressure Profile and Frost Buildup on the Aircraft Structure

Aircraft insulation separates the thermally comfortable cabin interior environment from the extremely cold outside conditions. However, the fabrication and installation of the insulation in the aircraft is a labor-intensive task. Tailored, rigid particle foam parts could be a solution to speed up the installation process. The presented study investigates the feasibility of such a concept from a hygrothermal point of view. Due to the temperature difference between the cold air trapped between aircraft skin and insulation on one side and the warm cabin air on the other side, a buoyancy-induced pressure difference forms. This effect drives the warmer air through leakages in the insulation system towards the cold skin. Here, moisture contained in the air condenses on the cold surfaces, increasing the risk for uncontrolled dripping (“rain in the plane”) when it melts. Therefore, this study compares the condensate build-up of different installations of a rigid particle foam frame insulation with the classical glass fiber capstrip. Tests are hosted in the Fraunhofer Lining and Insulation Test Environment chamber. It is shown that careful installation of the particle foam frame insulation provides similar level of moisture protection as the current state of the art insulation, and that the condensate amount does not depend on the amount of airflow directly behind the sidewall.

The impact of window-related thermal bridging on energy use in MURB retrofits using 2-d heat transfer modelling for full window thermal bridge analysis

There is significant in the GTA for GHG emissions reduction through energy retrofit measures of the more than 2000 post-war multi-unit residential buildings. Overcladding is an effective energy reduction strategy; however, it is crucial to properly detail window installation to avoid thermal bridging in a retrofit situation, as there may be excessive heat loss and condensation at this junction. This paper examines the thermal bridging potential at the window-wall interface in an EIFS overcladding retrofit scenario for a typical MURB retrofit. The research used the software THERM to compare influence of three typical window-wall interface on the energy performance of the window and wall. The analysis examined the position of the window within the frame, insulation placement around the window perimeter. It was found that window placement within the wall section and detailing at the opening do significantly affect the wall’s overall thermal performance, determining that design improvement should be considered and quantified in retrofit energy reduction strategies.

The impact of window-related thermal bridging on energy use in MURB retrofits using 2-d heat transfer modelling for full window thermal bridge analysis

There is significant in the GTA for GHG emissions reduction through energy retrofit measures of the more than 2000 post-war multi-unit residential buildings. Overcladding is an effective energy reduction strategy; however, it is crucial to properly detail window installation to avoid thermal bridging in a retrofit situation, as there may be excessive heat loss and condensation at this junction. This paper examines the thermal bridging potential at the window-wall interface in an EIFS overcladding retrofit scenario for a typical MURB retrofit. The research used the software THERM to compare influence of three typical window-wall interface on the energy performance of the window and wall. The analysis examined the position of the window within the frame, insulation placement around the window perimeter. It was found that window placement within the wall section and detailing at the opening do significantly affect the wall’s overall thermal performance, determining that design improvement should be considered and quantified in retrofit energy reduction strategies.

Design and Development of Power Driven Gari Fryer

A continuous process power driven gari fryer was designed, fabricated and tested at the Federal Institute of Industrial Research, Oshodi. (FIIRO), Lagos, to fry large quantity of cassava mash using locally available materials. The fryer which consists of major two sections; one to gelatinize cassava mash while the drying of the mash take place in the other section. The essential components of the fryer include feeder, frying troughs, rotating paddle arrangement, central shaft, coupling, top cover, gas burners, discharge sprout, main frame, insulation wall, sprocket and internal combustion engine. In operation, the rotating paddles convey the cassava mash during the gelatinization and drying process from the feeding point to the discharge sprout to obtain finished gari product. At constant speed of 8 rpm, the result showed that the time of frying ranged between 14 minutes to 17 minutes with an output of 83.2 kg/hr while the percentage yield of gari obtained ranged from 52.8% - 74.7%. Thus it is established that the capacity of the fryer is 500 kg per day as against the manual method of frying where 5 kg of gari is obtained within 30 minutes (80 kg/day) for 8 hours frying operation in local cassava processing industry in Nigeria. Hence, this makes the fryer to be suitable for gari production for small to medium scale enterprise.

Classification of quality conditions of a traction motor frame insulation of locomotives

The objective of the article is to determine the quality conditions of a locomotive traction motor frame insulation based on observations over the recovery voltage and classification of a tested insulation wear degree as well as to determine estimates of operating time until the insulation restoration or replacement with a new one. To classify the insulation quality conditions and to forecast its residual life until the restoration, a cluster analysis and discriminant analysis are used based on indicators reflecting the properties of an insulation recovery voltage curve. The study defines an information content received from frame insulation recovery voltage readings as compared with its resistance from the perspective of testing the insulation condition and predicting its residual life. Statistical characteristics of clusters corresponding to the insulation condition stages allow determining the limit values of predicting parameters and estimating the residual insulation life prior the restoration. To classify the insulation condition, an integrated evaluation of the insulation condition quality is proposed. Integrated evaluation is performed according to the recovery voltage curve and is used as an indicator during clustering. An experimental study of the proposed method practically confirmed its effectiveness.

Commissioning of thermal performance of prefabricated timber frame insulation elements for nZEB renovation

The current study contains a commissioning of thermal performance of highly insulated building envelope, located in cold and humid Estonian climate. The focus is on the renovation of old apartment building to nearly-zero energy building with prefabricated timber frame insulation elements with designed thermal transmittances U=0.10-0.12 W/(m2∙K). Air tightness, heat flux and temperatures were measured after renovation. Results of commissioning are showing some deviations from designed values, possibly caused by internal convection, improper tightening of joints of elements and poor quality of sealing of layers which must be kept airtight. The results have shown that analysis of designed solutions before, during and after renovation is worthwhile. Thorough inspection and strict rules of quality control on work site are essential for high-quality, sustainable outcomes of renovation with timber frame insulation elements and to guarantee designed thermal performance.