Experimental investigation on cross flow fan’s casing parameters inside of a split air conditioner indoor unit by Stereo Particle Image Velocimetry

In this study, the flow effects of a Cross Flow Fan (CFF) casing inside of a Split Air Conditioner (SAC) were parametrically investigated. Volute curvature, tongue angle, vortex wall angle and vortex wall distance to the CFF were selected as the investigation parameters. In addition, the existence of a heat exchanger was also tested to understand the relationship between these parameters and the heat exchanger. A total of 480 different design points were obtained through the combination of these parameters. To perform all of these experiments in a relatively short time, a half model parametric SAC prototype was designed. Each model was tested by Stereo Particle Image Velocimetry (SPIV) on the symmetry plane. After post processing of the results, evaluations were made according to selected output parameters, which were average velocity, projected air flow rate and vorticity. As the result of the study, standalone and overall flow effects of these parameters were presented. A full prototype of the design with the optimum outputs was built and investigated using SPIV. The full prototype's results were evaluated based on the results from the parametric prototype. (C) 2017 Elsevier Ltd. All rights reserved

Experimental visualization of the flow characteristics of the outflow of a split air conditioner indoor unit by meshed infrared thermography and stereo particle image velocimetry

Three-dimensional (3D) flow structures due to the interaction between the device edges, fan casing and cross flow fan (CFF) in the rectangular jet at the outflow of a split air conditioner (SAC) indoor unit were investigated by the stereo particle image velocimetry (SPIV) method. In addition, a novel application of infrared thermography called meshed infrared thermography (MIT), used to determine and visualize the temperature profile in an air flow field, was introduced for the first time and used to investigate the temperature distribution at the outflow section of the SAC indoor unit. The results of measurements that were made at different positions on the device were used to prepare three-dimensional reconstructions of the rectangular jet flow and temperature distribution at the outlet section. (C) 2012 Elsevier Inc. All rights reserved

A method for volumetric visualization of temperature distribution: three-dimensional meshed infrared thermography

In this study, a method called three-dimensional meshed infrared thermography (3D MIT) was developed to visualize the volumetric temperature of air using an infrared camera. The main operating principle of the proposed method is to image the spheres using an infrared camera and processing the images with computer software to obtain the volumetric temperature distribution. For the correct implementation of the method, an equation is proposed to determine the distance between the thermal target and the measurement target placed in the flow to be examined. The proposed method was compared with conventional measurement screen methods, namely those using a plane target and a high-porosity target, via particle image velocimetry (PIV) in terms of flow effects. The temperature measurement capability of the proposed method is presented in comparison with the results of thermocouple and conventional measurement screen-based measurements recorded using a jet flow. In addition, the volumetric temperature isosurfaces obtained via the 3D MIT method of a jet flow were compared with the volumetric velocity isosurfaces obtained via the PIV method in terms of the flow structure

Numerical and experimental investigation of liquid blowing agent and pentane blowing agent effects on the insulation of a household refrigerator

Refrigerators are the most energy demanding household devices since they are working 7/24. Improving insulation material is crucial for reducing this demand. One of the promising ways to improve insulation materials is to develop better-blowing agents. In this study, the effects of Liquid Blowing Agent (LBA) and Pentane Blowing Agent (PBA) on whole refrigerator insulation were investigated by experimental and numerical methods. The thermal conductivities of the insulation materials were measured by the hot-wire method. The experimental results show that LBA has a 32.08% lower thermal conductivity regarding conventional polyurethane with PBA. These experimental results utilized as boundary conditions for CFD model of the refrigerator. The numerical analysis suggests that LBA can decrease the refrigerators' heat loss between 5.52% and 19.34%