scholarly journals Experimental investigation of thermoelectric cooling system with heat recovery

2019 ◽  
Vol 100 ◽  
pp. 00020 ◽  
Author(s):  
Justyna Gołębiowska ◽  
Agnieszka Żelazna
Keyword(s):  
Water Temperature ◽  
Heat Recovery ◽  
Cooling System ◽  
Small Scale ◽  
Water Tank ◽  
Thermoelectric Cooling ◽  
Experimental Room ◽  
Domestic Water ◽  
Power Generators ◽  
Cooling Effects

Thermoelectric modules are implements used as power generators and cooling devices. In case of TE module application for space cooling, it is highly recommended to reuse energy generated on the hot side of the module for example for domestic water heating. In this paper, an example of a small scale thermoelectric cooling system with heat recovery was presented. In the tested system, the performance of TE module was supported by two heat exchangers. On the cold side of the TE module the forced convection was provided by the implementation of aluminium heat sink integrated with fan. On the hot side a water heat exchanger was built in order to reuse waste energy to heat water in the water tank. Different values of current were applied to the TE module to observe the differences in the module performance. The correlation between the air temperature inside the experimental room and the water temperature in the tank were determined for all conducted series. In general, the best cooling effects were achieved when the water temperature in the tank was not higher than 26.4°C. The maximum reduction of temperature inside the experimental room was noted for the amperage 7 A and it was 11.7°C.

Reactor Cavity Cooling System Facility Shakedown and RELAP5-3D Model Validation

2012 ◽  
Author(s):  
R. Vaghetto ◽  
Saya Lee ◽  
Y. A. Hassan
Keyword(s):  
Steady State ◽  
3D Model ◽  
Cooling System ◽  
Coolant Flow ◽  
Experimental Results ◽  
Normal Operation ◽  
Small Scale ◽  
Water Tank ◽  
Experimental Facility ◽  
Cavity Cooling

A small scale water-cooled experimental facility was built in order to study the complex thermohydraulic phenomena taking place in the Reactor Cavity Cooling System (RCCS) during the normal operation (steady-state case) an during accident scenario when forced convection is lost. The facility represents a portion of the reactor vessel with nine stainless steel coolant risers. The pipes are connected via cold and hot manifolds to a water tank located on top of the cavity. Due to the complexity of the expected thermal hydraulic phenomena, a RELAP5-3D input deck was prepared in order to predict the main thermohydraulic parameters, mainly coolant flow rate and temperatures. During the facility shakedown, the coolant flow was constantly monitored in order to observe the natural circulation startup phase and some interesting features of the coolant behavior were observed. The comparison of the preliminary experimental results from a test run with the prediction of the RELAP5-3D simulations helped validating the assumptions and simplifications adopted in the model for future simulations of steady-state and transients, and confirmed the potentiality of the system code for analysis of such systems. In the present paperwork, a detailed description of the experimental facility and the RELAP5-3D model are provided. Preliminary experimental results from different test runs are described and compared with the RELAP5-3D simulation results.

scholarly journals Development and Evaluation of an Ultrasonic Humidifier to Control Humidity in a Cold Storage Room for Postharvest Quality Management of Dates

Foods ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 949
Author(s):  
Maged Mohammed ◽  
Nashi Alqahtani ◽  
Hamadttu El-Shafie
Keyword(s):  
Quality Management ◽  
Cold Storage ◽  
Cooling System ◽  
Positive Impact ◽  
Droplet Diameter ◽  
Postharvest Quality ◽  
Main Element ◽  
Small Scale ◽  
Storage Room ◽  
Ultrasonic Humidifier

Dates are subjected to postharvest losses in quality and quantity caused by water loss, fermentation, insect infestation, and microbial spoilage during storage. Cold storage is the main element in the postharvest quality management used for fruit preservation. Although cold storage is used for dates, precision control of the relative humidity (RH) using ultrasonic applications is not used thus far, or it is applied to other fruits on a small scale. Therefore, we designed and constructed an ultrasonic humidifier (DUH) for RH control in the cold storage room (CSR) of dates. The optimum air velocity of 3 m s−1 at the outlets of the DUH ducts produced a mist amount of 6.8 kg h-1 with an average droplet diameter of 4.26 ± 1.43 µm at the applied voltage of 48 V and frequency of 2600 kHz of the transducers. The experimental validation was carried out by comparing a CSR controlled with the DUH with two conventional CSRs. The three tested CSRs were similar in dimensions, cooling system, and amount of stored dates. The time required for cooling 800 kg of dates in the controlled CSR from 25 °C to the target temperature of 5 °C was approximately 48 h. The DUH precisely controlled the RH at the maximum RH set point of 80% in the tested CSR at 5 °C. The controlled RH at 80% has a positive impact on the physicochemical characteristics of the stored dates. It significantly reduced the weight loss of the fruits and preserved fruit mass, moisture content, water activity, firmness, and color parameters. However, no significant effect was observed on fruit dimensions, sphericity, and aspect ratio. The microbial loads of mesophilic aerobic bacteria, molds, and yeasts fell within the acceptable limits in all tested CSRs. Both stored date fruits and artificially infested dates showed no signs of insect activity in the controlled CSR at the temperature of 5 °C and RH of 80%. The DUH proved to be a promising technology for postharvest quality management for dates during cold storage.

Development of Rotary Engine Based Micro-DG/CHP System

2016 ◽  
Author(s):  
Richard L. Hack ◽  
Max R. Venaas ◽  
Vince G. McDonell ◽  
Tod M. Kaneko
Keyword(s):  
Distributed Generation ◽  
Power Output ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Waste Heat ◽  
Pollutant Emissions ◽  
Small Scale ◽  
Rotary Engine ◽  
Chp System ◽  
Performance Results

Small scale Distributed Generation with waste heat recovery (<50 kW power output, micro-DG/CHP) is an expanding market supporting the widespread deployment of on-site generation to much larger numbers of facilities. The benefits of increased overall thermal efficiency, reduced pollutant emissions, and grid/microgrid support provided by DG/CHP can be maximized with greater quantities of smaller systems that better match the electric and thermal on-site loads. The 3-year CEC funded program to develop a natural gas fueled automotive based rotary engine for micro-DG/CHP, capitalizing upon the unique attributes engine configuration will be presented including initial performance results and plans for the balance of the program.

A Reduced-Order Model for the Preliminary Design of Small-Scale Radial Inflow Turbines

2021 ◽  
Author(s):  
Marco Manfredi ◽  
Marco Alberio ◽  
Marco Astolfi ◽  
Andrea Spinelli
Keyword(s):  
Heat Recovery ◽  
Internal Combustion Engines ◽  
Reduced Order Model ◽  
Pollutant Emissions ◽  
Small Scale ◽  
Preliminary Design ◽  
Order Model ◽  
Reduced Order ◽  
Wide Range ◽  
Loss Models

Abstract Power production from waste heat recovery represents an attractive and viable solution to contribute to the reduction of pollutant emissions generated by industrial plants and automotive sector. For transport applications, a promising technology can be identified in bottoming mini-organic Rankine cycles (ORCs), devoted to heat recovery from internal combustion engines (ICE). While commercial ORCs exploiting turbo-expanders in the power range of hundreds kW to several MW are a mature technology, well-established design guidelines are not yet available for turbines targeting small power outputs (below 50 kW). The present work develops a reduced-order model for the preliminary design of mini-ORC radial inflow turbines (RITs) for high-pressure ratio applications, suitable to be integrated in a comprehensive cycle optimization. An exhaustive review of existing loss models, whose development pattern is retraced up to the original approaches, is proposed. This investigation is finalized in a loss models effectiveness analysis performed by testing several correlations over six existing geometries. These test case turbines, operating with different fluids and covering a wide range of target expansion ratio, size, and gross power output, are then employed to carry out the validation procedure, whose results prove the robustness and prediction capability of the proposed reduced-order model.

Preliminary Evaluation of the 24 Ft. Diameter Fan Performance In the MinWaterCSP Large Cooling Systems Test Facility

2021 ◽  
Author(s):  
S. J. van der Spuy ◽  
D. N. J. Els ◽  
L. Tieghi ◽  
G. Delibra ◽  
A. Corsini ◽  
...  
Keyword(s):  
Scaling Laws ◽  
Static Pressure ◽  
Cooling System ◽  
Pressure Rise ◽  
Full Scale ◽  
Test Facility ◽  
Small Scale ◽  
Preliminary Evaluation ◽  
Cfd Analysis ◽  
Setting Angle

Abstract The MinWaterCSP project was defined with the aim of reducing the cooling system water consumption and auxiliary power consumption of concentrating solar power (CSP) plants. A full-scale, 24 ft (7.315 m) diameter model of the M-fan was subsequently installed in the Min WaterCSP cooling system test facility, located at Stellenbosch University. The test facility was equipped with an in-line torque arm and speed transducer to measure the power transferred to the fan rotor, as well as a set of rotating vane anemometers upstream of the fan rotor to measure the air volume flow rate passing through the fan. The measured results were compared to those obtained on the 1.542 m diameter ISO 5801 test facility using the fan scaling laws. The comparison showed that the fan power values correlated within +/− 7% to those of the small-scale fan, but at a 1° higher blade setting angle for the full-scale fan. To correlate the expected fan static pressure rise, a CFD analysis of the 24 ft (7.315 m) diameter fan installation was performed. The predicted fan static pressure rise values from the CFD analysis were compared to those measured on the 1.542 m ISO test facility, for the same fan. The simulation made use of an actuator disc model to represent the effect of the fan. The results showed that the predicted results for fan static pressure rise of the installed 24 ft (7.315 m) diameter fan correlated closely (smaller than 1% difference) to those of the 1.542 m diameter fan at its design flowrate but, once again, at approximately 1° higher blade setting angle.

Superalloy Cooling System for the Composite Rim of an Inside-Out Ceramic Turbine

2017 ◽  
Author(s):  
N. Courtois ◽  
F. Ebacher ◽  
P. K. Dubois ◽  
N. Kochrad ◽  
C. Landry ◽  
...  
Keyword(s):  
Gas Turbines ◽  
Cooling System ◽  
High Strength ◽  
Carbon Composite ◽  
Flow Rate Ratio ◽  
Small Scale ◽  
Inlet Temperature ◽  
Operating Temperatures ◽  
Critical Components ◽  
Inside Out

The use of ceramics in gas turbines potentially allows for very high cycle efficiency and power density, by increasing operating temperatures. This is especially relevant for sub-megawatt gas turbines, where the integration of complex blade cooling greatly affects machine capital cost. However, ceramics are brittle and prone to fragile, catastrophic failure, making their current use limited to static and low-stress parts. Using the inside-out ceramic turbine (ICT) configuration solves this issue by converting the centrifugal blade loading to compressive stress, by using an external high-strength carbon-polymer composite rim. This paper presents a superalloy cooling system designed to protect the composite rim and allow it to withstand operating temperatures up to 1600 K. The cooling system was designed using one-dimensional (1D) models, developed to predict flow conditions as well as the temperatures of its critical components. These models were subsequently supported with computational fluid dynamics and used to conduct a power scalability study on a single stage ICT. Results suggest that the ICT configuration should achieve a turbine inlet temperature (TIT) of 1600 K with a composite rim cooling-to-main mass flow rate ratio under 5.2% for power levels above 350 kW. A proof of concept was performed by experimental validation of a small-scale 15 kW prototype, using a commercially available bismaleimide-carbon (BMI-carbon) composite rim and Inconel® 718 nickel-based alloy. The combination of numerical and experimental results show that the ICT can operate at a TIT of 1100 K without damage to the composite rim.

scholarly journals Effect of Air Heat Pump Cooling System as a Greener Energy Source on the Air Quality, Housing Environment and Growth Performance in Pig House

Atmosphere ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1474
Author(s):  
Dhanushka Rathnayake ◽  
Hong-Seok Mun ◽  
Muhammad Ammar Dilawar ◽  
Il-Byung Chung ◽  
Kwang-Woo Park ◽  
...  
Keyword(s):  
Energy Source ◽  
Air Quality ◽  
Growth Performance ◽  
Heat Pump ◽  
Cooling System ◽  
Electricity Consumption ◽  
Housing Environment ◽  
Significant Difference ◽  
Cooling Effects ◽  
Carbon Dioxide Co2

The present study examined the cooling effects of an air heat pump (AHP) system. An AHP system was installed in a pig house to compare the effects with a traditional cooling system on the growth performance, noxious gas emission, housing environment and consumption of electricity. During the 19-week experimental trial, the internal temperature in the AHP cooling system-connected pig house was significantly decreased (p < 0.05) than the conventional house. Similarly, the temperature–humidity index (THI) was significantly reduced (p < 0.05) in the growing and late finishing period. The carbon dioxide (CO2) and electricity consumption were also reduced significantly in the AHP cooling system relative to the control. The concentration of ammonia (NH3) during the weaning and finishing phase and the concentration of hydrogen sulfide (H2S) during all periods were lower in the AHP-installed pig house (p < 0.05). From 0–19 weeks, there was no significant difference was observed (p > 0.05) in terms of the growth performance of pigs in both houses. These results show that the AHP cooling system can be implemented as an environmentally friendly renewable energy source in swine farms for sustainable pig production and better air quality without adversely affecting productivity parameters.

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