Xuehui Jing¹, Junchen Guo¹, Zhiyun Wang^2,*

Frontiers in Heat and Mass Transfer, Vol.22, No.3, pp. 919-937, 2024, DOI:10.32604/fhmt.2024.049689 - 11 July 2024

Abstract In this paper, the combustion conditions in the boiler furnace of a 660 MW tangential fired pulverized coal boiler are numerically simulated at 15% and 20% rated loads, to study the flexibility of coal-fired power units on ultra-low load operation. The numerical results show that the boiler can operate safely at 15% and 20% ultra-low loads, and the combustion condition in the furnace is better at 20% load, and the tangent circles formed by each characteristic section in the furnace are better, and when the boiler load is decreased to 15%, the tangent circles in… More >

Xuehui Jing^a,* , Wei Li^a, Zhaoyu Li^a , Zhiyun Wang^b

Frontiers in Heat and Mass Transfer, Vol.20, pp. 1-4, 2023, DOI:10.5098/hmt.20.19

Abstract This paper numerically simulates the combustion in a 300MW tangentially fired pulverized high-alkali coal boiler under low-load conditions. The combustion process, temperature distribution and the thermal load in the furnace at different height are analyzed under three different load conditions, which are 30%, 45% and 60% of full load. The temperature distribution and the variation of NO_x concentration under different load conditions are investigated, as well. The results show that the combustion processes of pulverized high-alkali coal in the furnace are similar under different load conditions, but the positions of the fuel’s full combustion are related… More >

Biqing Shu^1,2, Lu Hong³, Suxia Li^1,4, Yupeng Tao², Jianxin Cui¹, Naiqiang Fu², Junbao Yu², Chen Li², Xiaoning Lu^1,*

Journal of Renewable Materials, Vol.10, No.8, pp. 2203-2216, 2022, DOI:10.32604/jrm.2022.019882 - 25 April 2022

Abstract In this work, we used tensile tests to analyze the tangential failure forms of raw bamboo and determine a relationship between tangential tensile strength, elastic modulus, position, density, and moisture content. We found that the tangential mechanical properties of the culm wall were mainly dependent on the mechanical properties of the basic structure of the thin wall. Formulas for calculating the tangential tensile strength of moso bamboo and adjusting the moisture content were also determined. The tangential tensile strength and the tangential tensile modulus of elasticity (TTMOE) followed: outer > middle > inner, and diaphragm More >

Ke Zhou^1,2, Haitao Li^1,2,*, Assima Dauletbek^1,2, Dong Yang^1,2, Zhenhua Xiong³, Rodolfo Lorenzo⁴, Kun Zhou⁵, Ileana Corbi⁶, Ottavia Corbi⁶

Journal of Renewable Materials, Vol.10, No.1, pp. 165-182, 2022, DOI:10.32604/jrm.2021.017223 - 27 July 2021

Abstract Eccentric compression tests on 15 chamfered laminated bamboo lumber (LBL) columns with a height ranging from 600 to 3000 mm were conducted in order to study the eccentric mechanical performance. The failure of all specimens was caused by the crack of bamboo fiber in the tensile region. When the ultimate strength was reached, except specimens with a height of 600 mm, all other specimens could bear large deformation, showing good ductility. The lateral displacements of the specimens under eccentric compression were approximately parabolic in the direction of column height. The ultimate bending moment of LBL… More >

Nian Wang, Mingjie Zhang, Sulaiman Alsaleem, Lesley M. Wright, Je-Chin Han^*

Frontiers in Heat and Mass Transfer, Vol.13, pp. 1-13, 2019, DOI:10.5098/hmt.13.9

Abstract This study investigates turbine blade, leading edge cooling from normal or tangential impinging jets. These jets impinging on a semi-cylindrical, inner surface are constrained to discharge in a single direction. The downstream jets are affected by the crossflow originating from the upstream jets. To understand the thermal flow physics, numerical simulations are performed using the realizable k- turbulence model. Both the experimental and numerical results show crossflow is more detrimental to normal impinging jets than the tangential jets. Furthermore, with a significant temperature drop across the jet plate, designers must correctly interpret jet impingement results. More >

P. T. Hemamalini¹, S. P. Anjali Devi²

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.4, pp. 491-501, 2014, DOI:10.3970/fdmp.2014.010.491

Abstract The Rayleigh-Taylor instability (RTI) of two superposed ferrofluids subjected to rotation and a periodic tangential magnetic field is considered. Relevant solutions and related dispersion relations are obtained by using the method of multiple scales. More >

H.B. Chen

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.4, pp. 105-106, 2011, DOI:10.3970/icces.2011.020.105

Abstract The calculation of field values and their derivatives near the domain boundary through the boundary element method (BEM) will meet the nearly singularity problem, i.e. the boundary layer effect problem. The tangential derivatives of field values on the boundary often meet an obvious deduction of calculation accuracy. An effective algorithm was proposed by Chen et al. [1,2] to treat these two problems in the same time in elastic BEM and it was recently extended to calculate the second derivative values in potential problem [3]. This algorithm is based on the regularized formulations and is now More >

L. Palermo Jr., L.P.C.P.F. Almeida¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.2, pp. 83-88, 2008, DOI:10.3970/icces.2008.007.083

Abstract The differentiation of the kernels of integrals in the displacement BIE to obtain one for stresses increases the order of the kernel singularity and additional care are necessary to treat the improper integrals. The application of the tangential differential operator (TDO) can reduce the order of the kernel singularity when the stress BIE employs Kelvin type fundamental solutions. This paper presents the numerical formulation for the TDO to three-dimensional problems. The TDO uses the derivatives of the shape function for displacements instead of introducing another interpolation function. Furthermore, the paper shows the additional integrals for More >

L. Palermo Jr.¹, L.P.C.P.F. Almeida², P.C. Gonçalves³

Structural Durability & Health Monitoring, Vol.2, No.2, pp. 123-130, 2006, DOI:10.3970/sdhm.2006.002.123

Abstract The kernels of integrands are usually differentiated to obtain the general boundary integral equation (BIE) for stresses and its corresponding traction equation. An alternative BIE for stresses can be obtained when the tangential differential operator is introduced in problems using Kelvin type fundamental solutions. The order of the singularity is reduced with this strategy and the Cauchy principal value sense or the first order regularization can be used in the resultant BIE. The dual boundary element formulation with the BIE for tractions using the tangential differential operator is analyzed in the present study. Shape functions More >