Abstract: The invention provides a carbon dioxide-based polyurethane elastomer with damping and anti-fatigue aging properties and its preparation method. It is obtained from Component A and Component B; Component A includes: PTMG-1000 45˜60 parts, carbon dioxide-based polyol 25˜30 parts, poly-DOPO-ITA-pentanediol ester 10˜20 parts, BDO 3˜5 parts, water 0.3˜0.5 parts, N-methylimidazole 0.5˜0.8 parts, bis(2-dimethylaminoethyl) ether 0.1˜0.2 parts, needle-shaped nano-titanium dioxide 0.5 parts, hindered phenol 0.2˜0.5 parts, dibutyltin dilaurate 0.1˜0.3 parts, strontium chloride 0.005˜0.01 parts, rhodium chloride 0.02˜0.03 parts, foaming agent 0.2˜0.5 parts; Component B includes: carbon dioxide-based polyol 50˜55 parts, MDI-50 45˜50 parts, organic zinc 0.01˜0.02 parts, organic bismuth 0.01˜0.02 parts.

Abstract: A multi-coil microchannel heat exchanger includes a first coil including a first inlet header, a first outlet header and first microchannel tubes; a second coil including a second inlet header, a second outlet header and second microchannel tubes; a first inlet connector fluidly connected to the first inlet header; a first outlet connector fluidly connected to the first outlet header; a second inlet connector fluidly connected to the second inlet header; and a second outlet connector fluidly connected to the second outlet header. The first coil and the second coil are arranged successively along the length direction of the multi-coil microchannel heat exchanger. The multi-coil microchannel heat exchanger includes a first side and a second side along the length direction, the first inlet connector, the first outlet connector, the second inlet connector and the second outlet connector are all located at the first side.

Abstract: A method for estimating refrigerant charge for an HVACR system is provided. The method includes obtaining one or more system parameters during operation. The one or more system parameters include at least one of compressor suction superheat, system mass flow, expansion device mass flow or opening degree, compressor suction saturated temperature, and compressor discharge saturated temperature. The method also includes conducting a regression analysis on the one or more system parameters to determine one or more predictive parameters for estimating the refrigerant charge. The method further includes determining a predictive model based on regression analysis. The predictive model establishes a relationship between the refrigerant charge and the one or more predictive parameters. Also the method includes estimating the refrigerant charge based on the predictive model.

Abstract: A multi-coil microchannel heat exchanger includes a first coil including a first inlet header, a first outlet header and first microchannel tubes; a second coil including a second inlet header, a second outlet header and second microchannel tubes; a first inlet connector fluidly connected to the first inlet header; a first outlet connector fluidly connected to the first outlet header; a second inlet connector fluidly connected to the second inlet header; and a second outlet connector fluidly connected to the second outlet header. The first coil and the second coil are arranged successively along the length direction of the multi-coil microchannel heat exchanger. The multi-coil microchannel heat exchanger includes a first side and a second side along the length direction, the first inlet connector, the first outlet connector, the second inlet connector and the second outlet connector are all located at the first side.

Abstract: A method for estimating refrigerant charge for an HVACR system is provided. The method includes obtaining one or more system parameters during operation. The one or more system parameters include at least one of compressor suction superheat, system mass flow, expansion device mass flow or opening degree, compressor suction saturated temperature, and compressor discharge saturated temperature. The method also includes conducting a regression analysis on the one or more system parameters to determine one or more predictive parameters for estimating the refrigerant charge. The method further includes determining a predictive model based on regression analysis. The predictive model establishes a relationship between the refrigerant charge and the one or more predictive parameters. Also the method includes estimating the refrigerant charge based on the predictive model.

Abstract: A method for estimating refrigerant charge for an HVACR system is provided. The method includes obtaining one or more system parameters during operation. The one or more system parameters include at least one of compressor suction superheat, system mass flow, expansion device mass flow or opening degree, compressor suction saturated temperature, and compressor discharge saturated temperature. The method also includes conducting a regression analysis on the one or more system parameters to determine one or more predictive parameters for estimating the refrigerant charge. The method further includes determining a predictive model based on regression analysis. The predictive model establishes a relationship between the refrigerant charge and the one or more predictive parameters. Also the method includes estimating the refrigerant charge based on the predictive model.

Abstract: A method for estimating refrigerant charge for an HVACR system is provided. The method includes obtaining one or more system parameters during operation. The one or more system parameters include at least one of compressor suction superheat, system mass flow, expansion device mass flow or opening degree, compressor suction saturated temperature, and compressor discharge saturated temperature. The method also includes conducting a regression analysis on the one or more system parameters to determine one or more predictive parameters for estimating the refrigerant charge. The method further includes determining a predictive model based on regression analysis. The predictive model establishes a relationship between the refrigerant charge and the one or more predictive parameters. Also the method includes estimating the refrigerant charge based on the predictive model.