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A detailed study of the erratic circulation around an unbounded inclined plate under fluctuating temperature and isothermal mass dispersion was carried out with a chemical reaction. This work concentrated on the harmonic inclination of the plate in its plane, and the accurate solution of the non-dimensional governing formulations was made possible by the Laplace transform technique. To evaluate their impact on different profiles, the investigation examined a variety of physical factors, including phase inclination, chemical response variable, Schmidt number, thermal Grashof number, mass Grashof number, and duration. Notably, the speed per second increased with decreasing phase angle. Furthermore, a decrease in either the thermal radiation variable or the chemical response variable induced an increase in velocity. [ABSTRACT FROM AUTHOR]

The paper presents the modeling and simulation of heat transfer in ANSYS in a room of a house. The house is a three-room apartment located in Resita, Caras-Severin. The room where the heat transfer was studied is the coolest room in the apartment. The mathematical model of heat transfer was developed and then based on this mathematical model the numerical model with finite elements was elaborated, thus making possible the simulation of the thermal transfer in ANSYS. The results obtained can help the homeowner in the correct sizing of the heating system. [ABSTRACT FROM AUTHOR]

Heat treatment can substantially improve the quality of wood materials. Temperature is the most important factor during heat treatment affecting the properties of boards, so optimizing the treatment process should include careful investigation of thermal transfer phenomena. In this work, the transient heat transfer characteristics during the heat treatment of wood at 120 °C, 150 °C, and 180 °C were numerically studied per the temperature distribution and variation in sample boards. The heat transfer model was established by comparative analysis of the experimental data and simulation data. ANSYS software was used to simulate heat transfer during the process of wood heat treatment; simulation results were consistent with experimental results at average relative error within 5%. This accurate simulation of heat transfer within wood samples provides useful insight into the heat transfer mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the use of quartz optically stimulated luminescence (OSL) dating for determining fluvial overbank sedimentation rates over decades to centuries. For the study we took 11 samples from three cores from an embanked floodplain along the River Waal (Rhine) near Neerijnen (The Netherlands). We propose a measurement protocol for young fluvial quartz based on the single-aliquot regenerative dose procedure. Parameters for the protocol are chosen to isolate the fast OSL component, eliminate an ultrafast OSL component and avoid thermal transfer. The protocol shows excellent dose recovery and recycling ratios. For each sample, a Gaussian is fitted to the lower part of the equivalent dose distribution to obtain an estimate of the burial dose. We discuss the validity of the OSL ages using internal and external controls, and conclude that there is no evidence for large systematic offsets in the OSL ages. OSL based sedimentation rates are between ∼3 and 8mm/a, in line with previous estimates. [Copyright &y& Elsevier]

Abstract: The geological record preserved in coastal salt marshes provides an opportunity to determine past hurricane activity during the Late Holocene in New England, USA. High precision dating is important to correlate overwash sand layers associated with hurricane strikes between different sites along the coastline. Three different optical dating methods have been tested and compared with independent age control; i) optically stimulated luminescence from quartz, ii) infrared stimulated luminescence from K-feldspar, and iii) a subtraction method. Quartz and K-feldspar dating results for three samples in a core from Round Hill Beach Marsh are in stratigraphic order and they are consistent within errors with radiocarbon ages and with each other. Subtraction dating results agreed with the quartz and K-feldspar ages for two of the three samples, but the subtraction age of the youngest sample gave an age underestimate. Replicate equivalent dose values from quartz showed a larger variation than those from feldspars, and this resulted in larger errors for the quartz and subtraction ages than those based on feldspars. K-feldspar yields the most precise optical ages, but is complicated by the need to correct for anomalous fading. Both quartz and K-feldspar are suitable for optical dating of hurricane overwash deposits in New England. [Copyright &y& Elsevier]

Abstract: A next-generation drilling system, equipped with a thermal drilling device, is proposed for glacier ice. The system is designed to penetrate glacier ice via melting of the ice and continuously analyze melt-water in a contamination-free sonde. This new type of drilling system is expected to provide analysis data in less time and at less cost than existing systems. Because of the limited number of parameters that can be measured, the proposed system will not take the place of conventional drilling systems that are used to obtain ice cores; however, it will provide a useful method for quickly and simply investigating glacier ice. An electro-thermal drilling device is one of the most important elements needed to develop the proposed system. To estimate the thermal supply required to reach a target depth in a reasonable time, laboratory experiments were conducted using ice blocks and a small sonde equipped solely with heaters. Thermal calculations were then performed under a limited range of conditions. The experiments were undertaken to investigate the effects of the shape and material of the drill head and heater temperature on the rate of penetration into the ice. Additional thermal calculations were then performed based on the experimental results. According to the simple thermal calculations, if the thermal loss that occurs while heat is transferred from the heater to ice (in melting the ice) is assumed to be 50%, the total thermal supply required for heaters in the sonde and cable is as follows: (i) 4.8kW (sonde) plus 0W (cable) to penetrate to 300m depth over 10days into temperate glacier ice for which the temperature is 0°C at all depths and to maintain a water layer along 300m of cable; (ii) 10kW (sonde) plus 19–32kW (cable) to penetrate to 1000m depth over 1month into cold glacier ice for which the temperature is −25°C at the surface and 0°C at 1000m depth and to maintain a water layer along 1000m of cable; and (iii) 19kW (sonde) plus 140–235kW (cable) to penetrate to 3000m depth over 2months into an ice sheet for which the temperature is −55°C at the surface and 0°C at 3000m depth and to maintain a water layer along 3000m of cable. The thermal supply required for the cable is strongly affected by the thickness of the water layer, cable diameter, and the horizontal distance from the ice wall at which the ice temperature was maintained at its initial temperature. A large thermal supply is required to heat 3000m of cable in an ice sheet (scenario (iii) above), but penetration into glacier ice (scenarios (i) and (ii) above) could be realistic with the use of a currently employed generator. [Copyright &y& Elsevier]