Experimental and Numerical Study of Thermal Performance of an Innovative Waste Heat Recovery System

Vizitiu, Robert Ștefan; Burlacu, Andrei; Abid, C.; Verdeș, Marina; Bălan, Marius Costel; Brănoaea, Marius

doi:10.3390/app112311542

Cited by 5 publications

(5 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The two-stage heat recovery–storage system consists of the connection of a water-to-water heat exchanger (heat exchanger A) to a water-to-water heat exchanger with integrated PCM (heat exchanger B). Heat exchanger A was previously tested as a stand-alone heat recovery system, revealing a high efficiency of up to 76.7% in recovering low- and medium-temperature thermal energy [ 24 ].…”

Section: Methodsmentioning

confidence: 99%

Investigating the Efficiency of a Heat Recovery–Storage System Using Heat Pipes and Phase Change Materials

et al. 2023

Self Cite

View full text Add to dashboard Cite

This study presents an experimental and numerical investigation into the efficiency of a two-stage heat recovery–storage system for reducing the thermal energy losses in the industry. The system is designed to recover and store waste thermal energy from residual fluids using heat pipes for recovery and an environmentally friendly phase change material for heat storage. Experimental investigation was conducted using water as the primary agent and varying the temperature between 60 °C, 65 °C, and 70 °C at a constant flow rate of 24 L/min. The secondary agent, also water, was used at an initial temperature of 10 °C and the flow rate was varied between 1 L/min, 2 L/min, and 3 L/min. The results show that the system had a peak efficiency of 78.1% and was able to recover a significant amount of thermal energy. This study demonstrates the potential of this system to reduce the thermal energy losses in the industry and highlight the importance of further research and development in this field, as the industry is responsible for approximately 14% of the total thermal energy losses and finding efficient ways to recover and store waste thermal energy is crucial to achieving sustainable energy consumption.

show abstract

Section: Methodsmentioning

confidence: 99%

Investigating the Efficiency of a Heat Recovery–Storage System Using Heat Pipes and Phase Change Materials

et al. 2023

Self Cite

View full text Add to dashboard Cite

show abstract

“…The heat exchanger is a device that transfers heat from a high-temperature fluid to a lowtemperature one [1]. The tubular heat exchanger, a kind of wall-type heat exchanger, is widely applied in the fields of chemical [2], power [3], food [4], etc.…”

Section: Introductionmentioning

confidence: 99%

“…The logarithmic mean temperature difference (LMTD) is a crucial concept during the design of the heat exchanger. The LMTD method could be successfully employed only if two assumptions could be met: (1) the specific heat capacity and the mass flow rate of the hot and cold fluids are kept constant, and (2) the heat transfer coefficient is kept constant. Fortunately, both of the two assumptions are fulfilled during the convective-condensation process of the pure steam or the water vapor with a little NCG [8][9][10].…”

Section: Introductionmentioning

confidence: 99%

A Thermal Calculation Model for Tubular Condensing Heat Exchanger

Han,

Yang,

Yang

et al. 2023

Preprint

View full text Add to dashboard Cite

The condensing heat exchanger is commonly applied in various heat exchange systems. It can efficiently recover moisture and heat from the flue gas that contains water vapor. However, the convective-condensation heat transfer process is so complicated that no mature thermal calculation model is available. This study develops a thermal calculation model for the widely employed tubular condensing heat exchanger in industry. To characterize the degree of the heat and mass transfer, this study introduces two parameters, namely the sensible and latent heat transfer efficiencies of fin. The thermal calculations are conducted for the condensing heat exchangers reported in the literature to verify the proposed model by comparing it with the experimental data. The results show that the absolute error of the calculated sensible and latent heat transfer efficiencies is 0.0365 and 0.0268, respectively. Under the working conditions in this study, a maximum difference of 5.2 K has been acquired between the measured and calculated values of the outlet temperature. The relative error of the condensate water flowrate is mostly within ±5.0% and ±10.0% under the bare-tube and finned-tube conditions, respectively, with a maximum deviation of 0.7 and 1.4 kg h-1. This study provides a general model for designing and optimizing various tubular condensing heat exchangers accurately.

show abstract

“…Installation of condensing heat exchangers in boiler houses allowed to reduce the temperature of the flue gas being released, to condensate water vapor, and thus use the waste heat efficiently [1,2]. Despite that, the condensate film formed in the condenser also serves as a precipitator of solid particles, which are the biggest environmental pollution source in the case of incinerating biofuels [3][4][5].…”

Section: Introductionmentioning

confidence: 99%

“…Some studies investigate water vapor condensation in tubes when the amount of noncondensable gases is small. Results of such studies [5][6][7][8][9][10][11], etc., revealed that condensation usually takes place in the initial part of the test sections where the largest quantity of water vapor is condensed, and therefore high heat and mass transfer rates are obtained there. As for flue gas, the situation is the opposite since the gas typically contains more noncondensable gas and less water vapor.…”

Section: Introductionmentioning

confidence: 99%

Flue Gas Condensation in a Model of the Heat Exchanger: The Effect of the Cooling Water Flow Rate and Its Temperature on Local Heat Transfer

et al. 2022

View full text Add to dashboard Cite

In boiler houses, the biggest heat energy losses are caused by flue gas being released into the atmosphere. Installation of condensing heat exchangers allows reducing the temperature of the flue gas being released, condensation of water vapor, and, thus, efficient use of the waste heat. There are many investigations of average heat transfer in different types of condensing heat exchangers. They indicate also that the cooling water flow rate and its temperature are important parameters defining water vapor condensation efficiency. Investigations of local condensation heat transfer in condensing heat exchangers are very limited. Only recently experimental investigations of the flue gas temperature and Re number effect on local condensation heat transfer in the model of the condensing heat exchanger at a constant cooling water flow rate and its temperature have started being published. In this paper, for the first time, detailed experimental investigations of the cooling water flow rate and its temperature effect on local condensation heat transfer of the water vapor from the flue gas in the model of the condensing heat exchanger (long vertical tube) are presented. The results revealed that at higher flue gas Rein, the effect of the cooling water flow rate and its temperature has a stronger impact on local heat transfer distribution along the test section.

show abstract

Experimental and Numerical Study of Thermal Performance of an Innovative Waste Heat Recovery System

Cited by 5 publications

References 23 publications

Investigating the Efficiency of a Heat Recovery–Storage System Using Heat Pipes and Phase Change Materials

Investigating the Efficiency of a Heat Recovery–Storage System Using Heat Pipes and Phase Change Materials

A Thermal Calculation Model for Tubular Condensing Heat Exchanger

Flue Gas Condensation in a Model of the Heat Exchanger: The Effect of the Cooling Water Flow Rate and Its Temperature on Local Heat Transfer

Contact Info

Product

Resources

About