Examining the Impact of Conical Fin Shape on Hydrothermal Characteristics

Journal International Journal of Heat and Technology

DOI 10.18280/ijht.430104

Issue 1

Volume 43

This study examined the transformation of cone fins into truncated cone fins under low laminar forced convection heat transfer, focusing on their effects on heat transfer and steam condensation in a staggered heat sink arrangement. It calculated the outlet cold water temperature and included five cone shapes based on the tip-to-base diameter ratio, ranging from 0 to 0.8 in increments of 0.2 while keeping the surface area, height, and transverse pitch constant. The results showed that using a truncated conical fin instead of a conical fin decreased heat transfer, the convection heat transfer coefficient, and the steam condensation rate. An increased tip diameter to base diameter ratio further reduced these parameters due to less contact area between the fin base and the plate surface. Additionally, there was strong agreement between theoretical and experimental methods in calculating the outlet water temperature and convection heat transfer coefficient. The DOE suggested optimal working conditions in every heat sink sample, and when their results were validated experimentally, it found good agreement. Additionally, the DOE provided empirical relations to determine heat transfer rate, pressure drop and steam condensation rate as a function of Ps and Vw

Enhancing thermal efficiency of passive solar heating systems through copper chip integration: experimental investigation and analysis

Journal International Journal of Low-Carbon Technologies

DOI 10.1093/ijlct/ctae214

Volume 19

This study aims to upgrade the thermal performance of a passive solar system, specifically a Trombe wall (TW), by incorporating a metallic absorbent made of copper chips into its absorbent surfaces. The paper compares the thermal performance of a classic TW with that of a copper chip-enhanced TW. An experimental test was set up for classic and copper chip–TW systems, and a full-day experiment was conducted in January 2018 to investigate the thermal performance under the same operating conditions. The experimental data were used to verify a mathematical model based on energy balance. The theoretical study agreed well with the experimental data, with a maximum error of 11% in the absorbent surface temperature valuation. The results revealed that adding copper chips to the TW system boosts its performance by increasing heat gains and improving thermal efficiency. It improves thermal efficiency and enhances the mean room temperature by 12.44% and 14.1%, respectively.

Thermal and Hydraulic Evaluation of a Parabolic Trough Collector Using Different Types of Porous Filling in an Absorber Receiver: A Review

Journal International Journal of Heat and Technology

DOI 10.18280/ijht.420325

Issue 3

Volume 42

The large amount of energy consumed is produced as a result of the combustion of fossil fuels. This is due to the obvious pollution of the environment, the high cost and the possibility of running out of these sources that make alternative energy sources more important. Sunlight is a popular renewable energy source. Among the various alternatives, harnessing solar energy has become a promising option in all over the world being less expensive, environmentally friendly and impermeable. Parabolic collectors are an effective way to produce steam in thermoelectric power plants to convert radiant energy into thermal energy. However, these complexes can be improved by improving their design and modifying parameters related to thermal behavior. Heated receiver tubes are key components of a PTC device. These types of improvements can be achieved through use of Nano fluids and insert fins, or porous materials with in receiver tube to enhance the PTC performance. The current review papers seek to increase heat transfer in the receiver tube and reduce heat loss to improve convection fluid heat transfer

AN OVERVIEW OF HEAT SINK TECHNOLOGY

Journal International Journal of Applied Mechanics and Engineering

DOI 10.59441/ijame/192127

Issue 4

Volume 29

The heat sink dissipates heat from the hot source to the environment. Also, the heat sink can absorb heat from the hot surroundings. It comes in various designs. Electric and electronic equipment, chemical industries, refrigeration, air conditioning systems, power plants, and other thermal applications use this technology. A fin array, a metal device that uses passive and active cooling techniques to dissipate heat. The surface area of the fins can be improved to enhance the efficiency of the heat sink by increasing thermal conductivity. Transverse fins can have a variety of shapes, such as a parabolic, triangular, or rectangular profile. Rectangular profiles are the most common, especially in arrays with numerous fins. The goal of this research is to look back at how longitudinal rectangular fins are optimized for arrays with fins subject to forced and natural convection work.

Assessment of thermal performance of PV/T collectors under different enhancement methods: A review study

Journal AIP Conference Proceedings

DOI 10.1063/5.0171450

Issue 1

Volume 2862

Population expansion & economic development in the majority of the world's countries have raised global energy dem &. According to international energy agencies, developing countries' energy consumption is increasing faster than in industrialized countries, & they would need nearly twice their existing capacity to meet energy dem & by 2020. It is also predicted that global energy consumption will rise by 44 % between 2006 & 2030. As a result, alternative energy sources must be defined in order to meet our energy needs while conserving conventional petroleum-based fuels. Solar energy is a clean energy source. Renewable systems have the potential to fulfill a large amount of the world's energy consumption. It has stabilized the hurtful impact of carbon emmissions of enhanced world energy consumption, including the reduction of major fossils fuels in the field of clean technology. The PVT system generates At the same time, electrical & thermal power are produced. The goal of this hybrid system was to use a cooling PV panel to improve electricity efficiency while also utilizing thermal energy for heating. The majority of PVT system research has been on heat transfer through an air or water-based medium. Nanofluids & phase-change materials have been combined with working fluid in recent years to improve PVT thermal performance while also introducing certain design parameters.

Review of the Fin Optimization in the Heat Sink Design

Journal International Review of Mechanical Engineering

Publisher Praise Worthy Prize S.r.l

DOI 10.15866/ireme.v17i10.23824

Issue 10

Volume 17

Heat sink optimization aims to improve hydrothermal characteristics, minimize weight, and reduce costs. This paper reviews some theoretical, numerical, and experimental studies dealing with the optimization design of fins and heat sinks of different shapes from 1958 to 2023. In the theoretical aspect, one-dimensional conduction heat transfer equations are derived to determine the optimum dimensions of rectangular, triangular, and spine fins, which involve circular, conical, concave, and convex fins. While the numerical studies dealt with heat sink optimization using design parameters such as fin dimensions, number of fins, fin arrangements, inclined angle, performing fins with different shapes, and flow rate ranges. Additionally, experimental studies were carried out in order to investigate optimizing heat sinks in a similar manner to numerical studies. Some of these studies suggested empirical correlations that could be used to compute Nu number and friction factors, assisting the designer in planning a preliminary heat sink design

EVALUATING THE HEAT TRANSFER CHARACTERISTICS OF HYBRID NANOFLUID FLOW IN CIRCULAR DUCTS WITH CONSTANT HEAT FLUX

Journal ARPN Journal of Engineering and Applied Sciences

DOI 10.59018/0823235

Issue 16

Volume 18

Researchers have recently been interested in introducing solid nanoparticles into thermal systems in order to improve their thermal performance as a nanofluid. Researchers have investigated nanoparticle types, sizes, and concentrations using theoretical, numerical, and experimental approaches. In the present study, a hybrid nanofluid was utilized in two concentrations, namely (0.5% ZnO+0.5% SiO2-distilled water) and (1% ZnO+1% SiO2-distilled water), in a 45° inclined heated pipe at a constant heat flux of 12000 W/m2 and a range of 4000 to 12000 for the Re number. Initially, the performance of the test apparatus was evaluated using distilled water in the same conditions as the hybrid nanofluids experiment, and its results were compared to an empirical relation to ensure accurate results. The experimentation results indicated that the nanofluids significantly improved heat transfer coefficients when nanoparticle concentration increased in hybrid fluids. This indicates that increasing nanoparticle concentrations can substantially improve heat transfer coefficients. Using hybrid nanofluids with a concentration of 0.5% and 1% increases the heat transfer coefficient by 1.2 and 1.4 times compared to distilled water.

High performance evaluation of a PV/T hybrid system connected with a thermal store unit holding parafn wax

Journal International Journal of Low-Carbon Technologies

DOI 10.1093/ijlct/ctac087

Volume 17

The photovoltaic/thermal (PV/T) hybrid system combines a PV panel with a thermal collector to generate both electricity and heat energy. Several research have been conducted globally since the 1970s to increase its efciency utilising various methodologies. One type of enhancing approach employed in this industry is phase-change materials. The current study combined a parafn wax thermal storage unit with a typical PV/T hybrid collector (WPVT) and compared its performance with that of another comparable collector without a thermal store unit (TPVT). Both collectors were tested under actual weather circumstances from January to April 2021, with two water fow rates of 0.7 and 1.2 LPM. To analyse the rate of improvement in the PV/T system by adding a parafn wax store unit, energy and exergy were simulated. During the trial period, the WPVT system provided the maximum efciency fow rate of 1.2 LPM. It obtained around 60% efciency, which was around 1.4 times that of TPVT. Furthermore, the modelling results indicated that the WPVT system's maximum overall and exergy efciencies were projected to be around 74.44 and 12%, respectively.

Evaluation of the gas turbine unit in the Kirkuk gas power plant to analyse the energy and exergy using ChemCad simulation

Journal International Journal of Low-Carbon Technologies

DOI 10.1093/ijlct/ctac034

Volume 17

The purpose of the study is to evaluate the thermal performance of the gas turbine unit represented by (K3) under actual weather conditions by applying the first and second laws of thermodynamics to the design production of the unit (283.6 MW) at standard conditions (1 bar) and temperature (15 Celsius), which included the analysis of the unit's energy and available energy. Hence, to find out the weaknesses and losses in the system, ChemCad simulation has been used to estimate the effects of external factors (ambient temperature, compression ratio, and relative humidity) for a whole year on the performance of the turbine unit. Overall results showed that the maximum exergy efficiency was obtained in November; it was ∼37% when Ta was 19.39°C. The maximum efficiency was obtained at Ta equal to 19.39°C, which was ∼37.67%. Higher ambient temperature increases specific fuel consumption (SFC). The results show that the SFC for the practical and program calculations increases with the increase in the temperature of the external environment and reaches the maximum rate in the practical calculations in September (0.224) at 33.27°C. Thus, it economically affects the price of power production. Moreover, the results showed that the combustion chamber occupied the first place for the destruction of available energy, and the results of energy efficiency and available energy were 39.20% and 30.83%, respectively.

Evaluation of the gas turbine unit in the Kirkuk gas power plant to analyse the energy and exergy using ChemCad simulation

Journal International Journal of Low-Carbon Technologies

DOI 10.1093/ijlct/ctac034

Volume 17

The purpose of the study is to evaluate the thermal performance of the gas turbine unit represented by (K3) under actual weather conditions by applying the first and second laws of thermodynamics to the design production of the unit (283.6 MW) at standard conditions (1 bar) and temperature (15 Celsius), which included the analysis of the unit's energy and available energy. Hence, to find out the weaknesses and losses in the system, ChemCad simulation has been used to estimate the effects of external factors (ambient temperature, compression ratio, and relative humidity) for a whole year on the performance of the turbine unit. Overall results showed that the maximum exergy efficiency was obtained in November; it was ∼37% when Ta was 19.39°C. The maximum efficiency was obtained at Ta equal to 19.39°C, which was ∼37.67%. Higher ambient temperature increases specific fuel consumption (SFC). The results show that the SFC for the practical and program calculations increases with the increase in the temperature of the external environment and reaches the maximum rate in the practical calculations in September (0.224) at 33.27°C. Thus, it economically affects the price of power production. Moreover, the results showed that the combustion chamber occupied the first place for the destruction of available energy, and the results of energy efficiency and available energy were 39.20% and 30.83%, respectively.

Effect of air gap depth on Trombe wall system using computational fluid dynamics

Journal International Journal of Low-Carbon Technologies

DOI 10.1093/ijlct/ctac063

Volume 17

The present study aimed to develop a computational model to understand the effect of air gap depth on the Trombe wall (TW) system. The simulation was performed for midday of January 17, 2017, in Kirkuk City, Iraq; at this time, the solar intensity was at a maximum value equal to 487.1 W/m², the ambient temperature was 10.1°C, and the wind speed was 0.7 km/h. The result of the simulations is investigated with the experimental work in the literature. The various parameters, such as thermal efficiency, inlet and outlet temperatures from the air gap, room temperature, and air mass flow rate in the air gap channel, have been considered in the simulation. The comparison result showed a good agreement between the predicted results and experimental work. This research work will be useful for the research community to understand the effect of air gap depth in the TW system.

Assessment of the Thermal Performance of Hybrid PVT Collector by Integrating It with a PCM Storage Unit

Journal International Journal of Renewable Energy Research

Issue 3

Volume 11

Photovoltaic (PV) modules convert solar energy directly to electricity, whereas solar thermal collectors absorb solar energy to heat air or water. Over several years, photovoltaic/thermal (PV/T) systems, in which, during daytime, each PV module generates electricity and forms the absorbing surface of a solar thermal collector with heat generated transferred to air or water for space or water heating applications, where the objective in such systems is to achieve an optimal simultaneous useful electrical and heat output, were designed, constructed, and tested. The current study aims to evaluate the thermal performance of a hybrid PVT system by integrating it with an external PCM storage unit. Two similar hybrid PVT systems simultaneously conducted experiments to achieve the desired goal, one integrating with a PCM volume and the other without it, using a water flow rate ranging from 0.72 to 1.2 LPM. Simulations of both systems are compared for the extent to which PCM contributes to improving the performance of PVT collectors. Experiments have been conducted on both hybrid PV/T collectors simultaneously under actual weather conditions in the city of Kirkuk, Iraq, for four months, starting from January until the end of April 2021. The simulation results showed that the addition of the PCM storage unit to the PV/T collector had contributed to increasing the thermal performance of the WPVT collector by twice the thermal performance of the TPVT collector. The result obtained from the present study agrees well with other similar works.

The Effect of Adding Paraffin Wax to PVT Collector on Its Efficiency: A Practical Study

Journal International Journal of Renewable Energy Research

Issue 1

Volume 11

The efficiency of a PV plate is not more than 20%, depending on its type, because more than 80% of the solar radiation falling on the PV panel is not converted into useful energy. In order to increase the PV efficiency, several studies have been conducted to convert it to a hybrid PVT system by adding a heat exchanger to its back surface. The present study involves a comparison of the thermal performance between a conventional PVT and a modified PVT collector containing a layer of paraffin wax on the heat exchanger. An experimental platform was established in the Iraqi city of Kirkuk (latitude 35.467 north and longitude 44.38 east), and experiments were conducted in February 2020 in two parts. The first part is an experiment without water circulation, and the second part involves water circulation at a constant flow rate of 1 LPM. In the first part, the experiment result showed that paraffin wax caused a decrease in the electrical efficiency of the PV panel by 5.3% due to the temperature rise of the surface of the photovoltaic plate. On the other hand, the result of the second part of this study showed that the use of paraffin wax has an advantage in improving the total efficiency of the hybrid MPVT system, as it maintains its thermal efficiency of over 60% in periods after 12:00 p.m. as a result of storing thermal energy in the wax layer. Also, two mathematical relations were obtained that express the instantaneous efficiency for each collector.

Experimental investigation for a laboratory solar chimney; a practical study in Iraq

Journal International Review of Mechanical Engineering

Issue 2

Volume 10

The solar chimney is a type of passive solar system used for power and ventilation purposes. For the past decade, a lot of theoretical and experimental studies have been done to improve the thermal performance of a solar chimney by changing some design parameters. The aim of the present work is simulating the thermal performance of a solar chimney system that was investigated based on two parameters, such as heat flux and air gap height, under monitored operating conditions in the laboratory. For this purpose, a small solar chimney was built in the laboratory/Kirkuk Technical College. Experiments were conducted on the chimney by choosing three air gap heights (3, 4.5, and 6 cm) and the heat flux variation from 125 to 1000 W/m² in eight steps. The simulation results show that the maximum air velocity entering the chimney was obtained at a 3 cm air gap height, which is about 2.29 m/s at a heat flux of 1000 W/m². It was higher than the velocity of air gaps (4.5 and 6 cm) by 3.6% and 10.6%. The average temperature of the hot plate was also affected by the width of the air gap, as the maximum temperature at the air gap was small. The results also indicate that the maximum thermal efficiency of the system is obtained at the height of 3 cm, which is about 25% at a heat flux of 1000 W/m². On the other hand, the highest chimney efficiency is obtained at the height of 6 cm

Performance of solar pond integrated with photovoltaic/thermal collectors

Journal Energy Reports

DOI 10.1016/j.egyr.2020.11.037

Volume 6

This article aims to propose and study a new system design for renewable energy called photovoltaic/ solar pond. This new system involves cooling the arrays of the photovoltaic/thermal collectors, which are installed beside the salinity gradient solar pond with a heat exchanger that is installed behind each solar cell. Thermal energy gained by the photovoltaic/thermal collectors was stored in the heat storage zone using a heat exchanger system. An experimental assessment was performed to examine the thermal performance of the mini PV/solar pond. The experiments were carried out for five months, starting from September 2019 and ending in January 2020, in Kirkuk, Iraq. During this period, temperature, salinity, and power generation were recorded in real-time. The experimental results confirmed that the maximum total efficiency value of the system was 37.67% which was recorded in September. Besides, the highest value of the daily thermal efficiency was 30% for September, while the ultimate value of the daily electrical efficiency was 9.357% as recorded in December. The current result agrees well with other experimental studies in the same field

The Effect of Vibration on the heat transfer from a vertical plate: A Review

Journal Journal of Thermal Engineering

DOI 10.14445/23950250/IJTE-V6I3P101

Issue 3

Volume 6

The influence of free or forced convection heat transfer becomes an essential element in laminar and turbulent flows. There have been numerical and experimental methods introduced in studying the convection in tubes or plates with different angular positions for conditions such as temperature-dependent fluid density, constant wall temperature, and parabolic profile axial velocity at the tubes or plates' entrance. In all cases, heating and cooling have been considered. The current research is an extension to free or forced convection, where it unravels the effect of vibration on heat transfer performance of free or forced convection. This section presents the literature review to observe possible gaps in the literature concerning the topic under discussion, which informs further research.

Study the Effect of Granules Type of The Porous Medium on The Heat Transfer Enhancement for Double Pipe Heat Exchanger

Journal Tikrit Journal of Engineering Sciences

Publisher College of Engineering, Tikrit University.

DOI 10.25130/tjes.26.4.07

Issue 4

Volume 26

The current study includes the effect of the type of porous medium on the heat transfer enhancement for a double-pipe heat exchanger. Using the three types of the porous medium of balls (steel, ceramic, and glass) with diameters of 6.35, 6, and 7 mm, respectively. The tests were carried out on a locally manufactured heat exchanger consisting of a copper pipe with an inner diameter of 20 mm, an outer diameter of 22 mm, and a length of 1800 mm, fixed inside a pipe made of galvanized iron with the same length of copper pipe with an inner diameter of 50 mm and a thickness of 5 mm. The heat exchanger is insulated with a layer of glass wool to prevent leakage of heat to the area surrounding the exchanger. The tests were carried out on the heat exchanger in four cases: the three cases for porous medium and the case of the exchanger without porous medium. For all cases, identical operating conditions were used, which were inlet temperatures of hot and cold water determined at 63°C and 32°C, and Reynolds numbers from 1100 to 9750 for cold water and 415 to 7500 for hot water. The experimental results showed that the highest thermal conductivity was obtained when the ceramic balls were used, which was estimated to be approximately 219.302 W/°C and increased by 105.3%, 10.8%, and 4.3% for the cases without porous medium, glass balls, and steel balls, respectively. The effect of the pressure drop on the hot water side was recorded as the highest value for pressure drop when the ceramic balls were used and ranged from 0.5 to 19.5 mmHg and increased by 0.95% and 2.25% when compared with the results of two cases for balls (steel and glass), respectively.

Effect of air gap width on the evaluation of the trombe wall efficiency

Journal International Review of Mechanical Engineering

Publisher Praise Worthy Prize S.r.l

DOI 10.15866/ireme.v13i11.17860

Issue 11

Volume 13

This study examines the selection of the best air gap for a model passive solar system chosen for heating in a cold climate based on instantaneous efficiency. The experiments have been performed on a passive solar system, which has been constructed from insulation sandwich panels on all sides except the south façade, which has been built from insulation sandwich panels on all sides except the south façade, where a Trombe wall has been built in it, which is constructed from reinforced concrete, and its exterior surface has been painted with dark black color and covered with a single transparent glass layer. Five sets of experiments have been performed on the test system by changing the width of the air gap from 30 to 10 cm under the weather conditions in January 2017 in the city of Kirkuk (Iraq). The experimental results have shown that 33 to 36% of the energy absorbed by the Trombe wall has been converted to instantaneous energy provided to the heating space during the day. In addition, the results of the energy analysis of experimental equations have been produced to assess the efficiency of the system; they show that the 15 cm air gap has a better case when applying the same parameters. This result is consistent with an experimental study conducted.

Experimental investigation of a small passive solar system

Journal International Journal on Energy Conversion

Publisher Praise Worthy Prize S.r.l

DOI 10.15866/irecon.v7i2.16586

Issue 2

Volume 7

The present study deals with the thermal energy analysis of a passive solar heating system, which contains a massive wall (Trombe wall) of concrete with the dimensions of 0.9 m (width) × 1.4 m (height) × 0.1 m (thickness) inside a test room in the south direction, covered with a single and clear 6 mm thick glass; the external dimensions of the test room have been 1.5 m (length) × 1.0 m (width) × 1.5 m (height). Experiments on the thermal system have been executed using six widths of air gap, which varied between 10, 15, 20, 25, 30, and 35 cm in January 2017. The passive solar system has been built according to the full dimensions in Iraq at the Kirkuk Technical College, located at E44°50’ and N34°45’. Experiments have been carried out for six different depths of the air channel in actual weather conditions. Ventilation energy has been calculated by using the airflow rate equation. For each test, the energy has been calculated according to the weather for one day, with the hottest weather conditions. The results have been compared to choose the best case for this test room.

Effect of tube material on the fouling resistance in the heat exchanger

Journal 2nd International Conference for Engineering, Technology and Sciences of Al-Kitab, ICETS 2018

Publisher IEEE

DOI 10.1109/ICETS.2018.8724619

In this study, the heat resistance and thermal performance of the shell and tube heat exchanger were estimated using 0.1M of sodium chloride solution as hot fluid. Experiments were conducted on three material types of pipes (copper, aluminum, and 304-SS) under the same operating conditions for 175 hours. The hot water flows through tubes with a flow rate of 4 liters per minute and a temperature of 61°C. The cold water flows in the shell side with a flow rate and temperature of 1 liter per minute and 23°C, respectively. The results indicate that 304-SS is the best case for this working condition. It has less fouling resistance as well as a minimum reduction in the thermal units number and effectiveness compared to the copper case (32.45% and 34.6 %) and to an aluminum case.

Effect of some factors on the thermal performance of shell and tube heat exchanger

Journal Journal of Engineering and Applied Sciences

Publisher Medwell Journals

DOI 10.1109/ICETS.2018.8724619

Issue 3

Volume 12

This research aimed to study the effect of 0.1 M of HCl, H₂SO₄, and NaCl solutions at 61 °C on the thermal performance and corrosion behavior of commercially pure copper tubes in the used Shell and Tube Heat Exchanger (STHE). The tests are performed with a counter-flow arrangement for 120 h. The flow rates for the tube-side solution (aqueous solution) and shell-side solution (tap water) were adjusted and kept constant at 150 and 50 L h⁻¹, respectively. According to the obtained results, the greater decrease in thermal performance is observed in HC1 solution than in H2SO4 solution and finally in NaCl solution, with a decrease in percentage of 11.6, 10.1, and 6.9, respectively. Besides, the results of visual inspection of the interior tube walls degradation and variation of the used aqueous solution characteristics showed that the HCl acid solution is more corrosive than H₂SO₄ acid and NaCl salt solutions. The XRD analysis results revealed that the corrosion products are formed by more than one reaction mechanism and form different hydrated and complex corrosion products.

Theoretical Study of Thermal Performance of Rock Bed Storage

Journal Proceedings - 2015 2nd International Conference on Mathematics and Computers in Sciences and in Industry, MCSI 2015

Publisher IEEE

DOI 10.1109/MCSI.2015.57

In this theoretical study, heat transfer and pressure drop in two cases of rock bed thermal storage have been studied. In the first case, the equivalent diameter is changed when the mass flow rate per unit area is constant, and in the second case, it is inversely. The unsteady numerical simulation is employed to analyze the performance of the heat flow and temperature field in the storage. While the best thermal storage is obtain at equivalent diameter of 0.01 m., show that the relation of pressure drop decrease with increase in equivalent diameter except in a range of 0.025 to 0.038, which is constant

A comparative performance study of some thermal storage materials used for solar space heating

Journal Energy and Buildings

Publisher Elsevier

DOI 10.1016/j.enbuild.2008.11.005

Issue 4

Volume 41

One of the most common methods used in passive heating is the utilization of a massive wall for heat storage. Many factors affect the performance of the wall, such as the thickness and the media used for heat storage. A numerical study has been conducted on a zone heated by a thermal storage wall. Three different storage materials are examined, namely concrete, the hydrated salt CaCl₂·6H₂O, and paraffin wax (N-eicosane). A numerical model is presented in this paper that judges the suitability of these materials as thermal storage mediums under the actual weather conditions of Iraq. For that purpose, the room temperature fluctuation in the zone is evaluated for each material using different thicknesses for each wall. The study concluded that an 8-cm-thick storage wall made from the hydrated salt is capable of maintaining the comfort temperature in the zone with the least room temperature fluctuation.

An analytical and experimental evaluation of a heat sink under constant heat flow and forced convection heat transfer

Journal Journal of Engineering and Technological Sciences

Publisher ITB Institute for Research and Community Services,

DOI 10.5614/j.eng.technol.sci.2021.53.4.5

Issue 4

Volume 53

In this study, the exact transient differential equation was used to calculate the convection heat loss in a heat sink with a rectangular cross-section fin. The result of the analytic solution was compared to the result from experiments conducted on a standard heat sink. The experiments were performed at a constant heat flow of 9000 W/m² and a low airflow rate ranging from 12 to 100 cm³/s in seven steps. The comparative results showed that while there was good agreement between the experimental result and the exact solution, the average error ratio increased with an increase of the airflow rate. However, the maximum average error ratio between the experimental result and the exact solution did not exceed 6.4%. The maximum temperature distribution in the heat sink was obtained at a time of 900 s in all experiments.