During cross flow in a heat exchanger, heat transfer in the front portion of the tube is more compared to back portion of the tube. This is due to less formation of vortices at the backside of the tube. For uniform heat transfer to take place throughout the tube, it is necessary to increase the vortex formation at the rear side of the tube. The aim of this study is to explore the possibilities ...

In this paper, overall heat transfer coefficient and friction factor of water based γ-Al2O3 nanofluid in a double tube counter flow heat exchanger have been measured experimentally under turbulent flow condition. For better dispersion of γ-Al2O3 nanoparticles in distilled water, magnetic stirrer and ultrasonic vibrator (with a power of 240 kW and frequency of 35 kHz) were implemented. The stabi...

A plate-fin heat exchanger is a type of heat exchanger widely used in air conditioners, and tubes and fins are tightly assembled by the mechanical expansion process of tubes. The tube expansion process deforms the grooves inside the tube, and the groove shapes also affect the adhesion between tubes and fins. In this study, the adhesion and heat transfer performance affected by the tube expansio...

Heat exchangers play significant role in refrigeration and air conditioning systems. Ongoing research aims to improve, or at least maintain, the system performance while reducing the size, weight and cost of the heat exchangers. This in turn leads to lower system refrigerant charge and reduced environmental impact. Using heat exchangers with small tube diameters (less than 5 mm) instead of larg...

This work presents an experimental approach to study the refrigerant flow through capillary tube-suction line heat exchangers. Lateral heat exchanger performance with refrigerant HFC-134a was experimentally evaluated for a range of heat exchanger assemblies and operating conditions typically found in household refrigerators and freezers. Based on the resulting performance data base, the influen...

Finned-tube heat exchangers are predominantly used in space conditioning systems, as well as other applications requiring heat exchange between two fluids. The design of finned-tube heat exchangers requires the selection of over a dozen design parameters by the designer such as tube pitch, tube diameter, tube thickness, etc... Finned-tube heat exchangers are common devices; however, their perfo...

The effect of inlet humidity conditions and inclination angle on the air side thermal hydraulic performance of a brazed aluminum heat exchanger has been investigated experimentally. The crossflow heat exchanger had flat tubes and folded fins with fin and louver pitch of 2.1 mm and 1.4 mm, respectively. The glycol temperature was held nearly isothermal at 1C, while humidity of the 12C inlet air ...

Heat exchangers are the important equipments with a variety of industrial applications including power plants, chemical, refrigeration and air conditioning industries. Helically coiled heat exchangers are used in order to obtain a large heat transfer area per unit volume and to enhance the heat transfer coefficient on the inside surface. This paper deals with the CFD simulation of helical coile...

In this paper an algorithm of PID controller based on model predictive control is designed for a shell and tube heat exchanger. PID controllers and model predictive controls are two control algorithm mostly used these types of process applications. The three parameters of PID controller must be tuned to the process to obtain a satisfactory closed loop process performance. The model of the heat ...

An experimental study of heat transfer characteristics with and without insert was found using water –water system on 1-2 pass shell and tube heat exchanger. Experimental results such as exchanger effectiveness, overall heat transfer coefficient were calculated using with and without insert. There is improvement in overall heat coefficient, efficiency in using twisted tape. In all the process i...