9 results about "Not-To-Exceed" patented technology

The invention discloses a contact thermal resistance testing method based on an engine service variable temperature environment, and belongs to the field of aero-engine thermal management. According to the method, an experiment is carried out through a laser flash method transient measurement technology; then, the contact thermal resistance under different temperatures and pressure load conditions is measured, the highest environment temperature is tested to exceed 1000K required by technical indexes, the final contact thermal resistance result under the 573K non-pressure gravity placement condition calculated through a multi-scale contact thermal resistance estimation method is 3019.02 K.mm < 2 > / W, the error between the final contact thermal resistance result and an experimental measurement result is 5.19%, and the contact thermal resistance is not influenced by the maximum environment temperature and the final contact thermal resistance result under the 573K non-pressure gravity placement condition. And the requirements are met when the technical index error does not exceed 12%. According to the method, the change rule of the contact thermal resistance under different temperature and pressure conditions can be accurately predicted, and key support is provided for thermal matching and design of heterogeneous material high-temperature parts of aero-engines.

This invention discloses a boost pressure control method, which includes four stages: a self-learning inactive stage, a self-learning stabilization stage, a self-learning activation stage, and a self-learning update stage. In the self-learning update stage, based on the average actual boost pressure before and after filtering, the average throttle inlet pressure before and after filtering, the average of the minimum actual boost pressure before filtering, or the average of the maximum actual boost pressure before filtering, a self-learning update coefficient for the minimum or maximum boost pressure is calculated and updated to the corresponding operating condition. The corresponding operating condition refers to engine speed, load, intake air temperature, coolant temperature, target intake pressure, atmospheric pressure, and target boost pressure fluctuations all not exceeding a preset range and their average values ​​being the same. Finally, the minimum or maximum boost pressure of the current operating condition is updated based on the self-learning update coefficient. This invention can perform self-learning of boost pressure, including minimum and maximum boost pressure.

Control device (20) for an internal combustion engine (100) which controls an internal combustion engine (100) which includes an intercooler (7) which cools the intake air and an EGR flow path pipe (40) which returns a portion of the exhaust gas in an exhaust path to an upstream side of the intercooler (7) as EGR gas, wherein the control device (20) for the internal combustion engine (100) comprises: a moisture quantity calculation unit (301, 301B, 302, 302B, 302C, 302D) configured to calculate a total moisture quantity contained in a mixed gas obtained by mixing fresh air flowing into the charge air cooler (7) and the EGR gas; a dew condensation calculation unit (303) configured to calculate a dew condensation generation quantity (WQcon) in the charge air cooler (7) based on the total moisture quantity calculated by the moisture quantity calculation unit (301, 301B, 302, 302B, 302C, 302D); a dew condensation determination unit (303) configured to set an end dew condensation generation quantity (WQcon2) to 0 if the calculated dew condensation generation quantity (WQcon) does not exceed a predetermined threshold (SL), and to set the end dew condensation generation quantity (WQcon2) to the calculated dew condensation generation quantity (WQcon) if the calculated dew condensation generation quantity (WQcon) exceeds the predetermined threshold (SL); an EGR correction unit (304) configured to correct a flow rate of the returned EGR gas based on the final dew condensation generation quantity (WQcon2) set by the dew condensation determination unit (303); a first moisture quantity calculation unit (301, 301B) configured to calculate a first moisture quantity (WQair) which is a moisture quantity contained in the fresh air; and a second moisture quantity calculation unit (302, 302B, 302C, 302D) configured to calculate a second moisture quantity (WQegr) which is a moisture quantity contained in the EGR gas, wherein the total moisture quantity is a sum of the first moisture quantity (WQair) and the second moisture quantity (WQegr), wherein the second moisture quantity calculation unit (301, 301B, 302, 302B, 302C, 302D) is designed to calculate the second moisture quantity (WQegr) based on a fuel property, a target EGR rate (TEGR) of the EGR gas before correction by the EGR correction unit (304) and an intake air quantity (Qair), and wherein the EGR correction unit (304) contains an EGR gas correction table in which EGR gas correction amounts (HOSegr) for correcting the EGR gas according to the final dew condensation generation amount (WQcon2) are set such that as the final dew condensation generation amount (WQcon2) increases the EGR gas correction amount (HOSegr).

The invention provides an EGR (Exhaust Gas Recirculation) control method and system after an ignition system fails, and belongs to the technical field of engine exhaust gas recirculation rate control. According to the method, the ignition system is detected, and after it is detected that at least one part fails, the corrected target EGR rate after the various parts fail is determined; and the minimum value of the corrected target EGR rate after all the parts break down is obtained, the final target EGR rate is obtained, the final target EGR rate is limited to be not larger than the target EGR rate before the fault, and EGR control is conducted according to the final target EGR rate. According to the method, the possibility of engine knock occurring after the knock sensor breaks down can be effectively improved, and meanwhile the influence on emission, the dynamic property and oil consumption is avoided.

The application discloses an ammonia fuel low-speed engine test bench security system and a control method. a ) The control method comprises the following steps: a) sealing performance test before starting the ammonia fuel engine; b) normal starting and no-leakage operation of the ammonia fuel engine; c) starting and operation of the ammonia fuel low-speed engine with slight leakage of not more than 200 ppm; and d) starting and operation of the ammonia fuel low-speed engine with serious leakage of more than 200 ppm. The application recycles the leaked ammonia fuel into the ammonia evaporation tank outdoors under different working conditions of slight leakage or serious leakage of the ammonia fuel, ensures the safety of on-site personnel, and provides reliable guarantee for safe and reliable test running of the ammonia fuel low-speed engine.

This application discloses a diagnostic method, device, and computer storage medium for an engine, belonging to the field of fault diagnosis technology. The method includes: acquiring multiple actual fuel injection factors that adjust the actual fuel injection quantity of a vehicle engine in real time at preset time intervals within a preset time period; determining whether an engine fault exists by judging whether the multiple actual fuel injection factors exist under different engine operating conditions, and whether the multiple actual fuel injection factors under different engine operating conditions fall within a first fuel injection factor range corresponding to the engine operating condition and whether they fall within a preset second fuel injection factor range where the vehicle's exhaust emissions do not exceed emission limits. In this application embodiment, determining whether an engine fault exists by performing multiple conditional judgments on the actual fuel injection factors under different engine operating conditions makes engine fault diagnosis more accurate.

The application discloses an engine coolant temperature control method and device, the method comprises the following steps: first-order low-pass filtering processing is carried out on the actual coolant temperature to obtain the filtered actual coolant temperature; it is judged whether the actual coolant temperature switching condition is satisfied or not, if yes, the actual temperature adopts the filtered actual coolant temperature, otherwise, the actual temperature continues to adopt the actual coolant temperature; in the two temperature switching processes, the absolute value of the change rate does not exceed the preset change rate value; the target coolant temperature is obtained as the original target temperature, dynamic optimization is carried out to obtain the final target temperature, and closed-loop PID control is carried out on the engine coolant temperature according to the final target temperature and the actual temperature; including: original target temperature reset, original target temperature transition, original target temperature decrement and other conditions, and the priority is lower and lower. The application solves the problems of low closed-loop control precision and poor robustness when the target coolant temperature changes greatly.

The invention provides an EGR control method and system after a fan fault, and belongs to the technical field of engine exhaust gas recirculation rate control. According to the method, the fan is detected, and after it is detected that at least one fault happens to the fan, corrected target EGR rates of various faults are determined; and taking a minimum value of the corrected target EGR rate of each fault to obtain a final target EGR rate, limiting the final target EGR rate to be not greater than the target EGR rate before the fault, and performing EGR control according to the final target EGR rate. According to the method, different target EGR rates can be optimized according to the fan fault occurrence condition, meanwhile, dynamic adjustment and updating are continuously carried out, and knocking occurrence after the fault occurs is effectively improved.

A method for increasing a temperature of exhaust gas to a target temperature is provided. The method includes determining, by a controller, a target energy of the exhaust gas, and determining, by the controller, a target discharge amount based on the target energy. The method also includes determining, by the controller, a trade-off of engine performance corresponding to one or more of the target discharge amount, an engine speed, and a driver demand power, and determining, by the controller, an allowable heater power based on the trade-off. The method further includes operating, by the controller, a heater at a heater power command that does not exceed the allowable heater power to heat the exhaust gas to the target temperature.