Danfoss (China)

Abstract The leakage flow through a traditional labyrinth seal reduces the compressor capacity of an oil-free magnetic bearing centrifugal compressor. Also, the super-heated leakage flow pollutes the downstream coolant flow, affecting motor cooling. A novel design is introduced to utilize the pressure loss across the seal by injecting liquid refrigerant near the seal inlet. The liquid-injected seal also functions as an expansion valve, producing low-temperature wet vapor at the seal exit. The wet vapor is projected to be utilized for motor cooling. A multiphase numerical simulation is performed to quantify the compressor performance of the liquid-injected seal and traditional seal under adiabatic conditions. The numerical simulation utilizes a Eulerian-Eulerian approach with an equilibrium phase change model. This study evaluates the compressor performance at three-speed lines: N1, N2, and N3. The base case results are validated with the experimental findings, with a maximum error of 3% in compressor efficiency. The local distribution of vapor mass fraction, pressure, and temperature are analyzed. The numerical results show that the leakage flow in the liquid-injected seal is reduced by 95%, and the compressor capacity is increased by 2.9%.

<div class="section abstract"><div class="htmlview paragraph">Fatigue life of a component is influenced by multiple factors like material, manufacturing, load & geometric variations and due to this there is a huge scatter in both test & predicted life through simulations. There are different methods available to account for these variations while predicting fatigue life. However, whenever a fatigue simulation engineer tries to correlate predictions with test outcomes, he/she will face a challenge as to: How to account for scatter in test? How to compare predicted life through simulations with test data? How much difference between test outcome and predictions is acceptable? To address these challenges, authors have suggested two approaches in this paper – 1. Sample to Sample approach and 2. Statistical approach. This paper suggests a set of criteria under both these approaches to conclude confidently that the prediction model is able to match the test outcomes. Also, the paper highlights the kind of measurements that needs to be done and the statistical tools that needs to be used for such a correlation. This paper intends to help engineers to select appropriate design margin for fatigue of metallic components without being overly conservative and to validate their fatigue predictions with test outcomes.</div></div>

In our previous work, (S)‐6H‐1‐(5‐isoquinolinesulfonyl)‐2‐hydroxymethyl‐1‐pyrrolidine and (S)‐6H‐1‐(5‐isoquinolinesulfonyl)‐2‐chloromethyl‐1‐pyrrolidine displayed potent inhibitory activity. Therefore, with these two substances as lead compounds, we designed and synthesized their enantiomers to reveal the inhibitory effects of chirality on Rho kinase. It is found that their enantiomers exhibited much better Rho kinase inhibitory activity and strongly promoted synapse formation. Experimental autoimmune encephalomyelitis is a murine autoimmune disease used to study multiple sclerosis. With added antigens, the changes from C57BL/6 mice's limbs and tail was observed and scored by clinical evaluation. The synthetic compounds may simultaneously reduce symptoms of experimental autoimmune encephalomyelitis and inhibit inflammatory infiltration of the central nervous system. Thus, these compounds may be potential candidates for inhibition of Rho kinase and should be considered for further experimental study in relation to multiple sclerosis.

The consideration of the drivetrains behavior under real operating conditions is becoming increasingly important. While in the past decades it was good enough to have a rough knowledge about the operation conditions in field, a more accurate and detailed picture of the duty cycles is required today. Caused by specific and complex operation conditions the load deviation between different applications is significant. In many cases like e.g. lifetime calculation, a precise knowledge of field conditions leads to the more accurate calculated or simulated results. This paper covers the duty cycles investigation of a forwarder application in field including the measurement concept and implementation. Especially, the analysis of the load conditions, clustering algorithm and lifetime calculation is included. The load spectrum generation is consequently done based on comprehensive load cycle determination. The Aim of this work is to verify the calculation accuracy of the load spectrum by using the clustered and raw data. The outcome of the investigation gives an indicator for the load degree of the drivetrain. Here the developed method creates a new and fast possibility of data analysis and is applicable to most drivetrain applications. Furthermore, the collected data is used as reference for future investigation of the forwarder evolution.