Kualitas Produk Peralatan Pertanian Hasil Tempa Panas Pengrajin Pande Besi Melalui Penerapan Desain Dapur Perlakuan Panas Model Tutup

The problems encountered by artisan blacksmiths based on the field study results: unable to detect incineration temperature of wood charcoal in the crucibles, crusts occurrence on the metal surface of scrap component of spring leaf SUP 9 after heating process in the exposed model heating treatment. The solutions taken were by transforming the kitchen design, from exposed model heating treatment to closeted model heating treatment, which aimed to avoid oxidation on the incinerated metal, thus crusts do not occur on its surface. The kitchen wall of closeted model heating treatment was made from fireproof bricks, held heat resistance, and carried a stable thermal conductivity out of wood charcoal incineration. A digital thermocouple was installed in the closeted model heating treatment kitchen to accurately measure the temperature of wood charcoal incineration results. The closeted heating model treatment kitchen was designed portable. The solution methods applied field study and descriptive analysis. The study generated a result of sturdiness value with 18.8 HRC average for hoe products was below the standard of sturdiness value according to SNI 02-0331-1989 and generated a result of kitchen wall of closeted model heating treatment made from red bricks with cement as the fastener could not stand the heat. The conclusion for the application of kitchen design of closeted model heating treatment were the sturdity values achieved 58 HRC with SAE 900 C as the cooling lube and the wear rate achieved 0.000165605 gram/m. This meant the wear resistance property was low which met the standard according to SNI 02-0331-1989. Abstrak Permasalahan pengrajin pande besi sesuai hasil studi lapangan: temperatur pembakaran arang kayu di dalam kowi tidak dapat dideteksi, permukaan logam bekas komponen pegas daun SUP 9 timbul kerak setelah proses pemanasan di dalam dapur perlakuan panas model buka. Metode pemecahannya melakukan inovasi pada desain dapur perlakuan panas model buka dirubah menjadi desain dapur perlakuan panas model tutup yang bertujuan: material logam yang dipanasi tidak teroksidasi, sehingga permukaan logam tidak timbul kerak, dinding dapur perlakuan panas model tutup terbuat dari bata tahan api, mempunyai sifat tahan panas serta konduktivitas panas hasil pembakaran arang kayu stabil, dapur perlakuan panas model tutup dipasang termokopel digital agar temperatur hasil pembakaran arang kayu terukur dan akurat, dan dapur perlakuan panas model tutup dirancang dapat dipindah-pindah tempat. Metode pemecahannya menggunakan metode studi lapangan dan metode analisis deskriptif. Hasil-hasil temuan yang diperoleh angka kekerasan produk cangkul rata-rata 18,8 HRC masih di bawah angka kekerasan cangkul menurut SNI 02-0331-1989, dinding dapur perlakuan panas model buka terbuat bata merah dengan pengikat semen tidak tahan panas. Simpulan dengan penerapan desain dapur perlakuan panas model tutup, angka kekerasan mencapai 58 HRC dengan media pendinginan oli SAE 90 dan laju keausan 0.000165605 gram/m memenuhi SNI 02-0331-1989, sehingga sifat ketahanan ausnya rendah.

Photothermal and Reorientational Contributions to the Photomechanical Response of DR1 Azo Dye-Doped PMMA Fibers

This work is a comprehensive experimental and theoretical study aimed at understanding the photothermal and molecular shape-change contributions to the photomechanical effect of polymers doped with azo dyes. Our prototypical system is the azobenzene dye Disperse Red 1 (DR1) doped into poly (methyl methacrylate) (PMMA) polymer formed into optical fibers. We start by determining the thermo-mechanical properties of the materials with a temperature-dependent stress measurement. The material parameters, so determined, are used in a photothermal heating model—with no adjustable parameters—to predict its contribution. The photothermal heating model predicts the observations, ruling out mechanisms originating in light-induced shape changes of the dopant molecules. The photomechanical tensor response along the two principle axes in the uniaxial approximation is measured and compared with another independent theory of photothermal heating and angular hole burning/reorientation. Again, the results are consistent only with a purely thermal response, showing that effects due to light-induced shape changes of the azo dyes are negligible. The measurements are repeated as a function of polymer chain length and the photomechanical efficiencies determined. We find the results to be mostly chain-length independent.

Study on control strategy of output stability of wind-solar reservoir thermal system

In view of the landscape reservoir heat output coordinated control demand, based on the topology of the hybrid energy storage system of the three ports heating model, using the sunlight with the electricity output of the complementary and heat accumulation can be regulatory, intends to research a kind of based on photo-thermal storage heat and scenery electricity heating output port control method, in order to achieve the goal of fast and smooth regulating heat output fluctuations, The coordinated output control of integrated wind-landscape storage and heat collection is realized.

Quantifying heating biases in marine air temperature observations, ~1790 - present

<p>Accurate, long-term time series of near-surface air temperature (AT) are the fundamental datasets on which the magnitude of anthropogenic climate change is scientifically and societally addressed. Across the ocean, these (near-surface) climate records use Sea Surface Temperature (SST) instead of Marine Air Temperature (MAT) and blend the SST and AT over land to create datasets. MAT has often been overlooked as a data choice as daytime MAT observations from ships are known to contain warm biases due to the storage of accumulated solar energy. Two recent MAT datasets, CLASSnmat (1881 – 2019) and UAHNMAT (1900 – 2018), both use night-time MAT observations only. Daytime MAT observations in the International Comprehensive Ocean–Atmosphere Data Set (ICOADS) account for over half of the MAT observations in ICOADS, and this proportion increases further back in time (i.e. pre-1850s). If long-term MAT records over the ocean are to be extended, the use of daytime MAT is vital.</p><p> </p><p>To adjust for the daytime MAT heating bias, and apply it to ICOADS, we present the application of a physics-based model, which accounts for the accumulated energy storage throughout the day. As the ‘true’ diurnal cycle of MAT over the ocean has not been, to-date, adequately quantified, our approach also removes the diurnal cycle from ICOADS observations and generates a night-time equivalent MAT for all observations. We fit this model to MAT observations from groups of ships in ICOADS that share similar heating biases and metadata characteristics. This enables us to use the empirically derived coefficients (representing the physical energy transfer terms of the heating model) obtained from the fit for use in removal of the heating bias and diurnal cycle from ship-based MAT observations throughout ICOADS which share similar characteristics (i.e. we can remove the diurnal cycle from a ship which only reports once daily at noon). This adjustment will create an MAT record of night-time-equivalent temperatures that will enable an extension of the marine surface AT record back into the 18<sup>th</sup> century.</p>

Thermal energy control in building energy system

There is usually a waste of energy consumption in building systems. To help buildings reduce energy waste, the article established a building-sharing heat and power energy sharing system to achieve optimal energy allocation. Furthermore, the report determined the dual operation strategy model of using heat energy to determine power supply and electricity to determine heat energy. At the same time, we use stochastic programming and multi-objective optimization of the heating model and propose a two-level optimization model solution method based on the Benders decomposition algorithm. At the end of the thesis, the process was applied to actual cases to verify the method?s effectiveness.

Optimizing Induction Heating of WNiCo Billets Processed via Intensive Plastic Deformation

The aim of the work is to optimize the induction heating regime and propose a suitable deformation temperature for a pre-sintered powder-based tungsten heavy alloy workpiece subsequently processed via rotary swaging. The heating regime is designed with the help of numerical analyses and subsequent experiments. The first part of the study focuses on the theoretic background of the induction heating and comprises the development of a reliable induction heating model via performing electromagnetic simulations in two individual computational software packages (for verification). The second part of the study then involves the optimization of the heating regime using the designed numerical model. Last but not least, the predicted results are compared to the experimentally acquired results, and the optimized heating regime, applicable before experimental rotary swaging of the WNiCo workpiece, is proposed. The results of the microstructure analyses of the workpiece heated to the selected optimum deformation temperature of 900 °C showed that the designed induction heating procedure provided sufficient heating of the bulk of the workpiece (contrary to the lower swaging temperature), as the swaged microstructure featured well-deformed tungsten agglomerates. Furthermore, the analyses documented the high-quality oxidation-free surface of the particular workpiece (contrary to the higher swaging temperature).

Numerical Simulation of Ampacity in Advanced Electrical Conductors

Elevated temperature performance of advanced conductors are investigated with a one-dimensional joule heating model. Step-by-step development and validation of the ampacity prediction model are discussed and results from case studies are provided. A potential advantage of advanced electrical conductors is their relatively low density. Copper — as reference — is compared with carbon-based conductors and copper nanocomposites, on the basis of equivalent volume and equivalent weight. It is shown that while doped carbon nanotube (CNT) conductors may potentially result in an improved conductor compared with copper on a weight basis, ultra-conductive copper (UCC) can outperform copper on both volume and weight bases.

Eccentric tidal disruption event discs around supermassive black holes: dynamics and thermal emission

ABSTRACT After the tidal disruption event (TDE) of a star around a supermassive black hole (SMBH), if the stellar debris stream rapidly circularizes and forms a compact disc, the TDE emission is expected to peak in the soft X-ray or far ultraviolet (UV). The fact that many TDE candidates are observed to peak in the near UV and optical has challenged conventional TDE emission models. By idealizing a disc as a nested sequence of elliptical orbits that communicate adiabatically via pressure forces, and are heated by energy dissipated during the circularization of the nearly parabolic debris streams, we investigate the dynamics and thermal emission of highly eccentric TDE discs, including the effect of general-relativistic apsidal precession from the SMBH. We calculate the properties of uniformly precessing, apsidally aligned, and highly eccentric TDE discs, and find highly eccentric disc solutions exist for realistic TDE properties (SMBH and stellar mass, periapsis distance, etc.). Taking into account compressional heating (cooling) near periapsis (apoapsis), we find our idealized eccentric disc model can produce emission consistent with the X-ray and UV/optical luminosities of many optically bright TDE candidates. Our work attempts to quantify the thermal emission expected from the shock-heating model for TDE emission, and finds stream–stream collisions are a promising way to power optically bright TDEs.