家用厨房冷藏柜设计探讨

本文就家用厨房冷藏柜的设计进行了探讨，提出了在结构上采用单独机械室的概念，通过实验指明了适用的冷凝器型式。     

小太阳电暖器发热体引线温升不合格原因与对策

针对卤素管小太阳电暖器在进行GB4706.1-2006第11章发热试验时,经常出现灯管引线温升项目不合格的情况,本文分析检测不合格的原因,同时讨论了改进方法。     

浅谈电厂锅炉排烟温度过高的原因及控制对策

本文分析了电厂锅炉排烟温度过高的主要原因，阐述了控制电厂锅炉排烟温度的有效措施，提出了降低电厂锅炉排烟温度的管理对策。     

电梯运行阻力大、电动机温升过高的检验案例分析

我国是电梯使用大国,电梯的运行安全关乎人民的生命财产安全。曳引驱动部件是电梯的核心部件,传统的蜗轮蜗杆驱动能耗高、噪声大且易发生运行故障。该文作者在对某电梯定期检验时,发现其存在运行阻力大、电机温度高的现象,通过技术分析,发现其原因是由于蜗轮、蜗杆在制造安装过程中螺旋角不一致、制造公差超标、蜗杆轴的轴间游动间隙偏小,润滑和热补偿受阻而造成的。最后介绍了永磁同步曳引技术的优越性,给广大电梯使用单位选择产品提供了参考。     

高温热油泵机械密封泄漏分析与对策

通过对高温导热油泵使用的单端面波纹管式机械密封进行校核,经过对摩擦副端面比压、端面线速度和端面温度的核算,结合导热油特性曲线,发现摩擦副端面温度超过导热油气化温度是造成机封端面及波纹管结碳的主要原因。按照机械密封设计规范API 682-2014的使用标准对高温导热油泵的机械密封进行改型,通过增加辅助撤热系统,降低摩擦副端面温度,解决了高温导热油泵的机械密封因结焦碳化问题,为解决同类设备故障开拓了新的工作方向。     

3款厨房机械不合格

国家质检总局日前发布厨房机械国家监督抽查结果。抽查结果显示，3家企业的3种产品不符合标准的规定。本次厨房机械共抽查了浙江、广东2个省27家企业生产的30种产品。依据国家标准《家用和类似用途电器的安全第l部分：通用要求））GB4706．1-2005、（（家用和类似用途电器的安全厨房机械的特殊要求））GB4706．30-2008和经备案现行有效的企业标准及产品明示质量要求，     

家用电动电器绕组温升试验探析及其误差分析

在家用电器产品的测试中,温升试验也称为发热试验,它是用于衡量家用电器在正常通电使用情况下的绝缘性能水平的基本试验之一。众所周知,电器产品在通电的情况下,内部不免产生电能损耗。电热电器是通过导体的发热来达到加热的目的,损耗主要是绝缘介质损耗和热能的损耗,其外壳和基座等部位也会随加热过程而发热,从而影响到绝缘性和使用的安全性,因而必须限制这些部件的温升值。而对电动电器来说,其构造更决定了温升试验的重要性。由于电动器具的损耗不仅有绝缘介质的损耗,更主要来自于金属导体的有效电阻损耗以及磁体的涡流和磁滞损…     

轴类机械密封失效的原因与对策

机械密封在石油、化工企业的运转设备上广泛使用,具有密封性好、性能稳定、泄漏量少、摩擦功耗低、使用周期长等优点而被广泛使用,尤其适用于较高转速且对泄漏要求较高的轴类机件密封,同时也存在结构复杂,使用条件苛刻、价格昂贵及不易维修等弊端,特别是机械密封工艺条件温度,压力等工艺参数的影响直接关系到设备机械密封的性能和使用寿命。因此,找出机械密封失效原因及检修对策是保证企业安全生产、提高设备使用寿命的重要任务。     

诌议离心泵机械密封泄漏原因与对策

本文介绍了机械密封结构原理，分析了离心泵机械密封泄漏的原因、处理方法及检修过程中需要注意的问题。     

低温送风空调系统的风管得热与温升

探讨了由于较低的送风温度使送风系统在风管温升、风管得热等方面发生的变化,并用公式计算了常规系统和低温送风系统的风管温升和风管得热.计算分析表明,在相同的保冷水平下,低温送风系统的风管温升大于常规系统(为常规系统的1.5倍以上),而低温送风系统的风管得热则近似等于常规系统(为常规系统的1.09倍左右).     

Two-stage temperature rise in a thermoviscoplastic half-plane under impact

Summary A thermoviscoplastic constitutive model is used to treat uniaxial shock wave propagation in a material exhibiting rate-sensitive plasticity and thermal softening. Simple relations are obtained for the pressure jump as a function of the density jump, shock speed as a function of particle velocity, and pressure decay behind the shock front. Also, the model predicts a two-stage temperature rise, involving a jump at the shock front followed by a rise due to plastic dissipation (stress decay). The temperature rise and other quantities are predicted in the case of impact of titanium plates.With 4 Figures     

低温液体输送系统的温升计算

运用数学方法计算火箭发动机试验中推进剂在传输过程中的冷量损失,并与试验结果进行比较,验证了方法的有效性,为低温输送管路的设计提供依据.     

Calculation of energy dissipation and temperature rise of piezoelectric metal-insulator-metal structures

Equations are given for calculating the temperature rise of thin-film piezoelectric transducers as a result of dielectric, mechanical, and piezoelectric losses and currents in the presence of electrostatic and harmonic excitation. The results of the article can be used in the design of optoelectronic and acoustic measuring devices. Translated from Izmeritel'naya Tekhnika, No. 12, pp. 47–50, December, 1998.     

Modelling the temperature rise effect through high-pressure torsion

An approach composed of the thermodynamics-based dislocation model and the Taylor theory is used to investigate the evolution of microstructure and flow stress during high-pressure torsion (HPT). The incremental temperature rise is considered through the modelling of HPT. The temperature can affect the annihilation of dislocations and thus the dislocation density. The model predicts the dislocation density, sub-grain size and flow stress during HPT. The modelling results are compared with the experimental data and the modelling results without considering the incremental temperature rise. A remarkable agreement is observed between the modelling results with considering the temperature rise effect and the experimental data.     

Effective temperature rise during propagation of shock wave and high-speed deformation in metals

Two theoretical models are developed for the calculations of temperature rise during high-speed deformation and shock wave propagation. In the first model the calculations of the temperature distribution in metals during high-speed deformation are based on a model where the stationary high-speed deformation is considered as a propagation of shock wave with some fixed velocity in these metals. In this model the self-consistent system of equations describing the equation of state of metals and the conservation laws for momentum, energy and flow of energy is used for the determination of the temperature profile in the front of shock wave. The numerical calculations of the temperature distribution profile in shock wave front have been performed using the microscopic Thomas–Fermi–Dirac model for such metals as Al, Cu and Fe. In the second theoretical model the process of high-speed deformation is considered as an adiabatic process where a fraction of plastic deformation is converted into heat. The results of the numerical calculations of temperature rise during high-speed deformation in the dependence of strain to fracture are presented for metals: Al, Cu, Ni and Fe. It was shown that using these models the temperature during high-speed deformation can increase in different metals up to 1000 K.     

Prediction of surface temperature rise of ultrasonic diagnostic array transducers

Temperature rise at the surface of an ultrasound transducer used for diagnostic imaging is an important factor in patient safety and regulatory compliance. This paper presents a semianalytical model that is derived from first principles of heat transfer and is simple enough to be implemented in a commercial ultrasound scanner for real-time forecasting of transducer surface temperature. For modeling purposes, one-dimensional array transducers radiating into still air are considered. Promising experimental verification data are shown and practical implementation benefits of the model for thermal design and management of ultrasonic array transducers are discussed. In particular, the reduction in the amount of thermal characterization data required, compared to empirical models, shows promise.     

Measurements of the temperature rise ahead of a fatigue crack

Summary The temperature rise ahead of a fatigue crack has been measured using a Thermovision camera. Observations were made on three kinds of polymer and an austenitic stainless steel. The maximum temperature difference in macro-scale between the zone ahead of the crack and the bulk of the material was found to be, for the polymers, about 30°C at 725 N/min and amplitude o.1–0.8 kp/mm² and, for the steel, 14°C at 6000 N/min and amplitude 3.0–24.0 kp/mm².