Artificially roughened solar air heating technology – A comprehensive review

Energy, cost, and environmental concerns play a vital role in understanding governing parameters of distributor design in falling film evaporators. Distributor design is a hidden parameter in many experimental papers. The uniform distribution of liquid refrigerant over the tube bundle mostly depends on two‐phase liquid refrigerant and vapor refrigerant. This work conducted experiments with two distribution systems with and without separation of liquid‐vapor refrigerant after expansion valve for the same evaporator capacity with R134a as a refrigerant. Results reveal that; separating vapor refrigerant has a positive impact on the approach of the evaporator with an open system distributor arrangement. The highest delta T and lowest practice are found at a heat flux of 13.97 kW/m2 with an available system distributor compared to a closed system with a heat flux of 14.25 kW/m2. The open system arrangement in the distributor is the novel parameter for distributor design, ensuring uniform distribution with minimum pressure drop and dry suction. An open system distributor has an average 16.1% capacity increase over a closed system. The experimental analysis helps to understand different parameters for the design of distributors in falling film evaporators for uniform distribution.

Section: Experimental Setup For System Performancementioning

confidence: 99%

Section: Experimental Conditions and Proceduresmentioning

confidence: 99%

See 1 more Smart Citation

Experimental investigation on the effect of liquid phase and vapor phase separation over performance of falling film evaporator

Anjankar

Lakade

Padalkar

et al. 2022

“…They obtained an enhancement ratio of 11 when the heat sink with phase change material (1 vol.%) was heated at 7 W, while its counterpart having (0.5 vol.%) developed only 6.5. Khimsuriya et al (2022) carried out a 3D transient thermal analysis on a lithium-ion battery pack. The surrounding air cooled it.…”

Section: Introductionmentioning

confidence: 99%

Thermal management using nano coated heat sink for electric vehicle battery cooling

Rajmohan

Ramesh

Arulprakasajothi

et al. 2023

Transient heat transfer occurs in a wide array of heat exchange devices and those subjected to heat input. Effective control of heat energy during transient heat transfer is vital to increase the operating life and effectiveness of the device and equipment subjected to the heating and cooling cycle. Extended surfaces in the form of pin fins are used to augment cooling in applications like electric vehicle batteries, computers, transformers, drones, and microcontrollers. In this study, an attempt is made to examine the heating and cooling cycle, the time required to attain a target temperature, and the enhancement ratio of finned heat exchangers. The heat sink is provided with graphene nanocoating intended for electric vehicle battery cooling. The performance of the heat sink and its counterparts having two different types of pin fins, that is, circular and square, are compared. Four different heat inputs were considered, that is, 15, 25, 35, and 45 W. Three different target temperatures, that is, 46, 56, and 66°C, were accounted for during the comparison. It is concluded that the graphene nanoparticles facilitated enhanced heat transfer during the heating cycle when the input heat was 25 W and above. The square pin fins exhibited an enhancement ratio of 1.5, irrespective of the input heat energy.

“…Nanofluids consist of nanoparticles suspended in a fluid (Khimsuriya et al, 2022). They exhibit improved heat conductivity, thermal stability and minimal pressure drop (Deena et al, 2022).…”

Section: Introductionmentioning

confidence: 99%

Investigation of heat transport characteristics of titanium dioxide nanofluids with corrugated tube

Ugle

Arulprakasajothi

Padmanabhan

et al. 2023

The implications of cooling fluids with suspended titanium dioxide nanoparticles in augmenting the heat transfer rate in the heat exchanger are discussed. The application of corrugated tubes for increasing the effectiveness of heat exchangers is studied in this work. In deionized water, the nanofluid is synthesized to get three different volume concentrations (0.25%, 0.5%, and 1%). The nanofluid's flow rate varies to 100 L/h, 150 L/h, and 200 L/h, respectively. An experiment is carried out in three corrugated tubes made of copper, with pitch values of 18, 20, and 25 mm, respectively. Optimization is carried out to determine the influence of nanofluid concentration, the mass flow rate of the nanofluids, and the corrugation pitch over the heat transfer rate. It is concluded that increasing the volume concentration of the nanoparticles in deionized water and the mass flow rate of the nanofluid enhances the heat transfer rate in the heat exchanger.