scholarly journals Mass flow rate optimization in solar heating systems based on a flat-plate solar collector: A case study

2021 ◽  
Vol 12 (3) ◽  
pp. 061-071
Author(s):  
Samer Yassin Alsadi ◽  
Tareq Foqha
Keyword(s):  
Flat Plate ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Solar Collector ◽  
Optimization Problems ◽  
Heating System ◽  
Solar Heating ◽  
Outlet Temperature ◽  
Solar Systems

Little works considered the optimization of working fluids in solar systems. Engineers, designers and scientists are interested with the optimization problems, furthermore it is very important specially, for solar systems to improve the energetic behavior and increase their efficiencies as a conversion system of solar irradiance to a useful thermal power. According to the available literature, the criteria of optimization mainly relates to energetic and economic analysis (one of them or both). The analysis was based upon the maximum useful energy obtained from solar collector. Accordingly, the optimum mass flow rate was found aspires to infinity. The second analysis is based upon minimum cost of the unit of useful energy [$/W]. The optimum mass flow rate of solar air-heating flat-plate collector for the considered domestic solar heating system has been found 29 kg/h per square meters of solar collectors. This paper deals with a third criteria that is, the amount of the additional energy required to achieve the required task from the solar system by means of auxiliary heating system. In where both the outlet temperature and mass flow rate play crucial role in the heat exchange between the fluid in the collector loop and the fluid in the load loop.

Performance Analysis of the Low-Temperature Solar-Boosted Power Generation System—Part I: Comparison Between Kalina Solar System and Rankine Solar System

2012 ◽  
Vol 135 (1) ◽  
Author(s):  
Faming Sun ◽  
Yasuyuki Ikegami ◽  
Hirofumi Arima ◽  
Weisheng Zhou
Keyword(s):  
Power Generation ◽  
Solar System ◽  
Low Temperature ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Solar Collector ◽  
Operating Conditions ◽  
Kalina Cycle ◽  
Solar Systems

On the base of the two classical thermodynamic cycles (Kalina cycle and Rankine cycle), solar-boosted Kalina system (Kalina solar system) and solar-boosted Rankine system (Rankine solar system) with traditional nonconcentrating flat plate solar collector (FPSC) and evacuated tube solar collector (ETSC) are investigated in the present paper. The proposed solar systems are considered to be the hybrid of power generation subcycle and solar collector subcycle. Their electricity generating performances are compared under their respective optimal operating conditions to clarify which one is more competitive in solar utilization. Results show that ETSC is the better choice for the both solar systems. Further, the performance comparison shows that the low-temperature solar energy utilized in Kalina cycle is predominant to generate electricity. Meanwhile, the study also find that mass flow rate of the power generation subcycle, mass flow rate of the solar collector subcycle, mass fraction of ammonia and the regenerator performance are important operational parameters for high performance of the Kalina solar system. Finally, with the aid of the weather conditions of Kumejima Island in Japan, the perceptual knowledge for Kalina solar system by using an application case is shown in the paper.

scholarly journals Particle Optimization of Ceo2/Water Nanofluids in Flat Plate Solar Collector

2019 ◽  
Vol 9 (2) ◽  
pp. 1467-1474 ◽  
Keyword(s):  
Flat Plate ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Solar Collector ◽  
Volume Concentration ◽  
Particle Volume ◽  
Wide Range ◽  
Flat Plate Solar Collector ◽  
Flat Plate Collector

The present research focuses on the role of CeO2/water nanofluid for estimating the performance of flat plate solar collector in respect of energetic and exergetic performance. Based on our experimental findings on varying mass flow rate, the present analysis focuses on a wide range of concentrations to find optimum volume concentration for which thermal performance is maximum. CeO2/water nanofluid exhibits high thermal conductivity improvement (~41.7%at 1.5% volume concentration) and comparatively lower dynamic viscosity. Performance evaluation of flat plate collector is based on first law analysis and qualitative nature of energy flow based on second law analysis. Experiments indicate that for~1.0% particle volume concentration at a mass flow rate of 0.03 kg/s, maximum collector efficiency is obtained up to 57.1% instead of water as the base fluid. Exergetic efficiency observed 84.6%at optimum concentration (~1.0% particle volume) of nanofluid at0.01 kg/s flow rate.

scholarly journals Optimization Of The Flow Distribution In VGroove Flat Plate Solar Collector using Cfd Simulation

2019 ◽  
Vol 8 (3) ◽  
pp. 4177-4182
Keyword(s):  
Flat Plate ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Solar Collector ◽  
Flow Distribution ◽  
Uniform Flow ◽  
Dynamics Simulation ◽  
Uniform Flow Distribution ◽  
Flat Plate Solar Collector

Flat plate solar collector is the major component of a solar heating system that converts solar radiation to thermal energy. It provides clean energy at no operating cost, however, its poor performance constitutes a serious drawback to adopt it for small application. This inefficiency is the result of involved thermal losses and the lack of full exploitation of the available energy. To exploit the maximum potential, the working fluid flow should be uniformly distributed through the collector to extract the heat from the hot absorbing surface. This study addresses the uniformity of the flow distribution for v-groove flat plate solar collector for water heating to optimize the performance of the collector. The study investigated the effect of the manifold geometry and the number of the side riser channels on the flow distribution by using numerical computational fluid dynamics simulation on Ansys Fluent Software. The mass flow rate was optimized for maximum thermal performance and then the optimum point was used for investigating the flow distribution. The simulation was validated against experimental data from literature with 99% confidence. The study found that the circular manifold gives uniform flow distribution with a standard deviation of 5% at the optimum mass flow rate of 11.5g/s. the study concluded that the tapered circular manifold is the optimum geometry for uniform flow distribution as it provides the least pressure difference inside the manifold.

Thermodynamic Performance Evaluation of a Solar Parabolic Dish Assisted Multigeneration System

2019 ◽  
Vol 141 (6) ◽  
Author(s):  
Muhammad Abid ◽  
Muhammad Sajid Khan ◽  
Tahir Abdul Hussain Ratlamwala
Keyword(s):  
Heat Transfer ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Solar Collector ◽  
Integrated System ◽  
Heat Transfer Fluid ◽  
Outlet Temperature ◽  
Parabolic Dish ◽  
Single Effect

The concentration ratio of the parabolic dish solar collector (PDSC) is considered to be one of the highest among the concentrated solar power technologies (CSPs); therefore, such system is capable of generating more heat rate. The present paper focuses on the integration of the PDSC with the combined cycle (gas cycle as the toping cycle and steam cycle as the bottoming cycle) along with the utilization of waste heat from the power cycle to drive the single effect lithium bromide/water absorption cycle. Molten salt is used as a heat transfer fluid in the solar collector. The engineering equation solver (EES) is employed for the mathematical modeling and simulation of the solar integrated system. The various operating parameters (beam radiation, inlet and ambient temperatures of heat transfer fluid, mass flow rate of heat transfer fluid, evaporator temperature, and generator temperature) are varied to analyze their influence on the performance parameters (power output, overall energetic and exergetic efficiencies, outlet temperature of the receiver, and as coefficient of performance (COP) and exergy efficiencies) of the integrated system. The results show that the overall energy and exergy efficiencies are observed to be 39.9% and 42.95% at ambient temperature of 27 °C and solar irradiance of 1000 W/m2. The outlet temperature of the receiver is noticed to decrease from 1008 K to 528 K for an increase in the mass flow rate from 0.01 to 0.05 kg/s. The efficiency rate of the power plant is 38%, whereas COP of single effect absorption system is 0.84, and it will decrease from 0.87 to 0.79. However, the evaporator load is decreased to approximately 9.7% by increasing the generator temperature from 47 °C to 107 °C.

Solar Radiation Model Applied to a Low Temperature Evacuated Tubes Solar Collector

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Oscar A. López-Núñez ◽  
J. Arturo Alfaro-Ayala ◽  
J. J. Ramírez-Minguela ◽  
J. Nicolás Flores-Balderas ◽  
J. M. Belman-Flores
Keyword(s):  
Low Temperature ◽  
Solar Radiation ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Solar Collector ◽  
Outlet Temperature ◽  
Radiation Model ◽  
Solar Radiation Model ◽  
Evacuated Tubes

A solar radiation model is applied to a low temperature water-in-glass evacuated tubes solar collector to predict its performance via computational fluid dynamics (CFD) numerical simulations. This approach allows obtaining the transmitted, reflected, and absorbed solar radiation flux and the solar heat flux on the surface of the evacuated tubes according to the geographical location, the date, and the hour of a day. Different environmental and operational conditions were used to obtain the outlet temperature of the solar collector; these results were validated against four experimental tests based on an Official Mexican Standard resulting in relative errors between 0.8% and 2.6%. Once the model is validated, two cases for the solar collector were studied: (i) different mass flow rates under a constant solar radiation and (ii) different solar radiation (due to the hour of the day) under a constant mass flow rate to predict its performance and efficiency. For the first case, it was found that the outlet temperature decreases as the mass flow rate increases reaching a steady value for a mass flow rate of 0.1 kg/s (6 l/min), while for the second case, the results showed a corresponding outlet temperature behavior to the solar radiation intensity reaching to a maximum temperature of 36.5 °C at 14:00 h. The CFD numerical study using a solar radiation model is more realistic than the previous reported works leading to overcome a gap in the knowledge of the low temperature evacuated tube solar collectors.

Optimum Utilisation of CuO Nanofluid in Flat Plate Solar Collector

2021 ◽  
Vol 17 (4) ◽  
pp. 8384-8396
Author(s):  
Nang Khin Chaw Sint ◽  
I. A. Choudhury ◽  
H. H. Masjuki
Keyword(s):  
Flat Plate ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Solar Collector ◽  
Base Fluid ◽  
Maximum Efficiency ◽  
Ambient Temperatures ◽  
Flat Plate Solar Collector ◽  
Flat Plate Collector

The optimum utilisation of CuO-nanofluid in flat plate solar collector has been investigated under Malaysian climatic condition. To determine the optimum nanoparticle concentration required in the base fluid, a simulation was carried out using MATLAB program. From the simulation, it was found that, 0.5 vol.% of CuO nanoparticles in the base fluid yielded maximum collector efficiency. The test was conducted over six months following the ASHRAE standard with nanofluid in the flat plate collector to ascertain its efficiency. The maximum average solar radiation incident on the collector, collector outlet and ambient temperatures were observed about 1000 W/m2, 50 ºC and 38 ºC respectively. From the efficiency curve, the absorbed and removed energy parameters were found to be 0.501 and 24.23 respectively. At a mass flow rate of one litre per minute, the maximum average instantaneous efficiency was 51%. The result of experimental efficiency was compared with the result of simulation and the efficiency values were within 4% of each other. CuO nanofluid base collector increases the efficiency compared to water as the collector fluid. The experimental results revealed that the efficiency of FPSC with CuO nanofluid was 4.78% higher than water base collector at the same mass flow rate of 1 L/min. The uncertainty analysis of result has shown that instantaneous efficiency uncertainty was about 3.3%. The simulation result has indeed minimised number of experiments required to determine the optimum concentration of nanofluid for maximum efficiency.

scholarly journals Energy efficiency of a flat-plate solar collector using thermally treated graphene-based nanofluids: Experimental study

2020 ◽  
Vol 10 ◽  
pp. 184798042096461 ◽  
Author(s):  
Omer A Alawi ◽  
Haslinda Mohamed Kamar ◽  
Hussein A Mohammed ◽  
AR Mallah ◽  
Omar A Hussein
Keyword(s):  
Energy Efficiency ◽  
Flat Plate ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Solar Collector ◽  
Fluid Mass ◽  
Pentaethylene Glycol ◽  
Flat Plate Solar Collector ◽  
Thermally Treated

A covalent functionalization approach was utilized for the preparation of highly dispersed pentaethylene glycol-thermally treated graphene-water as the absorbing material inside a flat-plate solar collector. Four mass fractions of nanofluids were prepared (0.025, 0.05, 0.075, and 0.1 wt% pentaethylene glycol-thermally treated graphene-water). Graphene nanoparticles were characterized by energy dispersive X-ray analysis with a scanning electron microscope. Measurements of the thermophysical properties were subsequently carried out for the nanosuspensions. The raw investigation data were collected from an indoor flat-plate solar collector test setup. The experimental procedure included different sets of variables such as input temperatures of 303, 313, and 323 K; fluid mass flow rate of 0.00833, 0.01667, and 0.025 kg s−1; and heat flow density of 500, 750, and 1000 W m−2. The thermophysical tests of pentaethylene glycol-thermally treated graphene-water nanofluids showed a proportional increase against weight concentrations, while the specific heat power was reduced. The tests showed an increment in energy efficiency by increasing the fluid mass flow rate and heat input. By comparison, the thermal efficiency decreased with the increasing temperature of the fluid supply. Relative to the base fluid, the energy efficiency of pentaethylene glycol-thermally treated graphene/water-based flat-plate solar collector increased to 10.6%, 11%, and 13.1% at the three fluid mass flow rates. In conclusion, an exponential form was used to derive the thermal effectiveness of flat-plate solar collector based on the experimental data.

Sign in / Sign up

Export Citation Format

Share Document