Heat Transfer to a Liquid Flowing Down Vertical Wires Hanging in a Hot Gas Stream: an Experimental Study of a New Means of Thermal Energy Recovery

1998 ◽  
Author(s):  
Takashi Nozaki ◽  
Nobufuji Kaji ◽  
Yasuhiko H. Mori
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Thermal Energy ◽  
Energy Recovery ◽  
Hot Gas

Direct Contact Gas-Liquid Heat Exchange for Energy Recovery

1990 ◽  
Vol 112 (3) ◽  
pp. 216-222 ◽  
Author(s):  
James R. Fair
Keyword(s):  
Heat Transfer ◽  
Mass Transfer ◽  
Heat Exchange ◽  
Experimental Work ◽  
Direct Contact ◽  
Energy Recovery ◽  
Gas Discharge ◽  
Transfer Data ◽  
Hot Gas ◽  
Liquid Heat

Energy from hot gas discharge streams can be recovered by transfer directly to a coolant liquid in one of several available gas-liquid contacting devices. The design of the device is central to the theme of this paper, and experimental work has verified that the analogy between heat transfer and mass transfer can be used for design purposes. This enables the large amount of available mass transfer data for spray, packed, and tray columns to be used for heat transfer calculations. Recommended methods for designing the several types of gas-liquid contacting device are summarized.

scholarly journals Experimental Study of Impingement Effusion-Cooled Double-Wall Combustor Liners: Thermal Analysis

Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4843
Author(s):  
Thomas Jackowski ◽  
Maximilian Elfner ◽  
Hans-Jörg Bauer
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Outer Wall ◽  
Heat Fluxes ◽  
Major Influence ◽  
Cooling Effectiveness ◽  
Hot Gas ◽  
Longitudinal Specimen ◽  
Circular Holes ◽  
Double Wall

A new experimental study is presented for a combustor with a double-wall cooling design. The inner wall at the hot gas side features effusion cooling with 7-7-7 laidback fan-shaped holes, and the outer wall at the cold side features an impingement hole pattern with circular holes. Data have been acquired to assess the thermal and aerodynamic behavior of the setup using a new, scaled up, engine-similar test rig. Similarity includes Reynolds, Nusselt, and Biot numbers for hot gas and coolant flow. Different geometrical setups are studied by varying the cavity height between the two walls and the relative alignment of the two hole patterns at several different blowing ratios. This article focuses on the thermal performance of the setup. The temperature data are acquired using two infrared systems on either side of the effusion wall specimen. In addition to cooling effectiveness evaluations, finite element simulations are performed, yielding the locally resolved wall heat fluxes. Results are presented for three cavity heights and two longitudinal specimen alignments. The results show that the hot gas side total cooling effectiveness can achieve values as high as 90% and is mainly influenced by the effusion coverage. Impingement cooling has a small influence on overall effectiveness, and the area of influence is mainly located upstream where effusion cooling is not built up completely. The analyzed geometric variations show a major influence on cavity flow and impingement heat transfer. Small cavities lead to constrained flow and high local Nusselt numbers, while larger cavities show more equalized Nusselt number distributions. A present misalignment shows especially high influence at small cavity heights. The largest cavity height, in general, showed a decrease in heat transfer due to reduced jet momentum.

scholarly journals Towards development of a prototype high-temperature latent heat storage unit as an element of a RES-based energy system (part 2)

2016 ◽  
Vol 64 (2) ◽  
pp. 401-408
Author(s):  
J. Karwacki ◽  
K. Bogucka-Bykuć ◽  
W. Włosiński ◽  
S. Bykuć
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Energy Storage ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Heat Storage ◽  
Heat Transfer Fluid ◽  
Storage Unit ◽  
Latent Heat Storage ◽  
Shell And Tube

Abstract This paper presents an experimental study performed with the general aim of defining procedures for calculation and optimization of shell-and-tube latent thermal energy storage unit with metals or metal alloys as PCMs. The experimental study is focused on receiving the exact information about heat transfer between heat transfer fluid (HTF) and phase change material (PCM) during energy accumulation process. Therefore, simple geometry of heat transfer area was selected. Two configurations of shell-and-tube thermal energy storage (TES) units were investigated. The paper also highlights the emerging trend (reflected in the literature) with respect to the investigation of metal PCM-based heat storage units in recent years and shortly presents unique properties and application features of this relatively new class of PCMs.

scholarly journals Experimental study of the potential for thermal energy recovery with thermoelectric devices in low displacement diesel engines.

Heliyon ◽  
2021 ◽  
pp. e08273
Author(s):  
R. Ramírez-Restrepo ◽  
A. Sagastume-Gutiérrez ◽  
J. Cabello-Eras ◽  
B. Hernández ◽  
J. Duarte-Forero
Keyword(s):  
Experimental Study ◽  
Thermal Energy ◽  
Diesel Engines ◽  
Energy Recovery ◽  
Thermoelectric Devices

Investigation of Potential Benefits of Using Bricks of High Thermal Capacity and Conductivity in a Rotating Calcining Kiln

2008 ◽  
Author(s):  
Lei Zhao ◽  
Ting Wang
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Heat Capacity ◽  
Potential Energy ◽  
Thermal Energy ◽  
Energy Savings ◽  
Thermal Capacity ◽  
K Value ◽  
Hot Gas ◽  
The Impact

Petroleum coke is processed into calcined coke in a rotary kiln, where the temperature profiles of flue gas and coke bed are highly nonuniform due to different flow and combustion mechanisms. Motivated by saving energy costs, the effect of refractory brick’s thermal properties on potential energy savings is investigated. This study focuses on investigating potential energy savings by replacing inner one third of existing bricks with higher thermal capacity (Cp) and/or higher thermal conductivity (k) bricks. This investigation is motivated by postulating that the bricks with higher thermal capacity can store more thermal energy during the period of contacting with the hot gas and release more heat to the cock bed when the bricks rotate to below and in contact with the coke bed. A rotational, transient marching conduction numerical simulation is conducted using the commercial software FLUENT. The impact of brick heat capacity and thermal conductivity on transporting thermal energy to the coke bed is analyzed. The results show: (a) Increasing the heat capacity of brick layer reduces brick temperature which helps increase the heat transfer between the hot gas and brick, in other words it does help brick store more heat from the hot gas, but, heat transfer between brick and coke is reduced, which is opposite to the original postulation. (b) Higher brick thermal conductivity decreases brick temperature thus increases heat transfer between hot gas and the brick layer. The heat transfer from brick to coke bed is also increased, but not significantly. (c) Usually a brick with a higher Cp value also has a higher k-value. Simulation of a brick layer with both four times higher Cp and k values actually show appreciable heat is transported from the brick to the coke bed for one rotation for both lower and higher Cp and k bricks. The difference is not significant.

Sign in / Sign up

Export Citation Format

Share Document